Vendor import of clang trunk r301939:vendor/clang/clang-trunk-r301939

https://llvm.org/svn/llvm-project/cfe/trunk@301939

190 files changed, 4593 insertions, 3101 deletions

diff --git a/docs/SanitizerCoverage.rst b/docs/SanitizerCoverage.rst
index d69afba4daca..1c42b4236a93 100644
--- a/docs/SanitizerCoverage.rst
+++ b/docs/SanitizerCoverage.rst
@@ -8,202 +8,12 @@ SanitizerCoverage
 Introduction
 ============
 
-Sanitizer tools have a very simple code coverage tool built in. It allows to
-get function-level, basic-block-level, and edge-level coverage at a very low
-cost.
-
-How to build and run
-====================
-
-SanitizerCoverage can be used with :doc:`AddressSanitizer`,
-:doc:`LeakSanitizer`, :doc:`MemorySanitizer`,
-UndefinedBehaviorSanitizer, or without any sanitizer.  Pass one of the
-following compile-time flags:
-
-* ``-fsanitize-coverage=func`` for function-level coverage (very fast).
-* ``-fsanitize-coverage=bb`` for basic-block-level coverage (may add up to 30%
-  **extra** slowdown).
-* ``-fsanitize-coverage=edge`` for edge-level coverage (up to 40% slowdown).
-
-At run time, pass ``coverage=1`` in ``ASAN_OPTIONS``,
-``LSAN_OPTIONS``, ``MSAN_OPTIONS`` or ``UBSAN_OPTIONS``, as
-appropriate. For the standalone coverage mode, use ``UBSAN_OPTIONS``.
-
-Example:
-
-.. code-block:: console
-
-    % cat -n cov.cc
-         1  #include <stdio.h>
-         2  __attribute__((noinline))
-         3  void foo() { printf("foo\n"); }
-         4
-         5  int main(int argc, char **argv) {
-         6    if (argc == 2)
-         7      foo();
-         8    printf("main\n");
-         9  }
-    % clang++ -g cov.cc -fsanitize=address -fsanitize-coverage=func
-    % ASAN_OPTIONS=coverage=1 ./a.out; ls -l *sancov
-    main
-    -rw-r----- 1 kcc eng 4 Nov 27 12:21 a.out.22673.sancov
-    % ASAN_OPTIONS=coverage=1 ./a.out foo ; ls -l *sancov
-    foo
-    main
-    -rw-r----- 1 kcc eng 4 Nov 27 12:21 a.out.22673.sancov
-    -rw-r----- 1 kcc eng 8 Nov 27 12:21 a.out.22679.sancov
-
-Every time you run an executable instrumented with SanitizerCoverage
-one ``*.sancov`` file is created during the process shutdown.
-If the executable is dynamically linked against instrumented DSOs,
-one ``*.sancov`` file will be also created for every DSO.
-
-Postprocessing
-==============
-
-The format of ``*.sancov`` files is very simple: the first 8 bytes is the magic,
-one of ``0xC0BFFFFFFFFFFF64`` and ``0xC0BFFFFFFFFFFF32``. The last byte of the
-magic defines the size of the following offsets. The rest of the data is the
-offsets in the corresponding binary/DSO that were executed during the run.
-
-A simple script
-``$LLVM/projects/compiler-rt/lib/sanitizer_common/scripts/sancov.py`` is
-provided to dump these offsets.
-
-.. code-block:: console
-
-    % sancov.py print a.out.22679.sancov a.out.22673.sancov
-    sancov.py: read 2 PCs from a.out.22679.sancov
-    sancov.py: read 1 PCs from a.out.22673.sancov
-    sancov.py: 2 files merged; 2 PCs total
-    0x465250
-    0x4652a0
-
-You can then filter the output of ``sancov.py`` through ``addr2line --exe
-ObjectFile`` or ``llvm-symbolizer --obj ObjectFile`` to get file names and line
-numbers:
-
-.. code-block:: console
-
-    % sancov.py print a.out.22679.sancov a.out.22673.sancov 2> /dev/null | llvm-symbolizer --obj a.out
-    cov.cc:3
-    cov.cc:5
-
-Sancov Tool
-===========
-
-A new experimental ``sancov`` tool is developed to process coverage files.
-The tool is part of LLVM project and is currently supported only on Linux.
-It can handle symbolization tasks autonomously without any extra support
-from the environment. You need to pass .sancov files (named 
-``<module_name>.<pid>.sancov`` and paths to all corresponding binary elf files. 
-Sancov matches these files using module names and binaries file names.
-
-.. code-block:: console
-
-    USAGE: sancov [options] <action> (<binary file>|<.sancov file>)...
-
-    Action (required)
-      -print                    - Print coverage addresses
-      -covered-functions        - Print all covered functions.
-      -not-covered-functions    - Print all not covered functions.
-      -symbolize                - Symbolizes the report.
-
-    Options
-      -blacklist=<string>         - Blacklist file (sanitizer blacklist format).
-      -demangle                   - Print demangled function name.
-      -strip_path_prefix=<string> - Strip this prefix from file paths in reports
-
-
-Coverage Reports (Experimental)
-================================
-
-``.sancov`` files do not contain enough information to generate a source-level 
-coverage report. The missing information is contained
-in debug info of the binary. Thus the ``.sancov`` has to be symbolized
-to produce a ``.symcov`` file first:
-
-.. code-block:: console
-
-    sancov -symbolize my_program.123.sancov my_program > my_program.123.symcov
-
-The ``.symcov`` file can be browsed overlayed over the source code by
-running ``tools/sancov/coverage-report-server.py`` script that will start
-an HTTP server.
-
-
-How good is the coverage?
-=========================
-
-It is possible to find out which PCs are not covered, by subtracting the covered
-set from the set of all instrumented PCs. The latter can be obtained by listing
-all callsites of ``__sanitizer_cov()`` in the binary. On Linux, ``sancov.py``
-can do this for you. Just supply the path to binary and a list of covered PCs:
-
-.. code-block:: console
-
-    % sancov.py print a.out.12345.sancov > covered.txt
-    sancov.py: read 2 64-bit PCs from a.out.12345.sancov
-    sancov.py: 1 file merged; 2 PCs total
-    % sancov.py missing a.out < covered.txt
-    sancov.py: found 3 instrumented PCs in a.out
-    sancov.py: read 2 PCs from stdin
-    sancov.py: 1 PCs missing from coverage
-    0x4cc61c
-
-Edge coverage
-=============
-
-Consider this code:
-
-.. code-block:: c++
-
-    void foo(int *a) {
-      if (a)
-        *a = 0;
-    }
-
-It contains 3 basic blocks, let's name them A, B, C:
-
-.. code-block:: none
-
-    A
-    |\
-    | \
-    |  B
-    | /
-    |/
-    C
-
-If blocks A, B, and C are all covered we know for certain that the edges A=>B
-and B=>C were executed, but we still don't know if the edge A=>C was executed.
-Such edges of control flow graph are called
-`critical <http://en.wikipedia.org/wiki/Control_flow_graph#Special_edges>`_. The
-edge-level coverage (``-fsanitize-coverage=edge``) simply splits all critical
-edges by introducing new dummy blocks and then instruments those blocks:
-
-.. code-block:: none
-
-    A
-    |\
-    | \
-    D  B
-    | /
-    |/
-    C
-
-Tracing PCs
-===========
-
-*Experimental* feature similar to tracing basic blocks, but with a different API.
-With ``-fsanitize-coverage=trace-pc`` the compiler will insert
-``__sanitizer_cov_trace_pc()`` on every edge.
-With an additional ``...=trace-pc,indirect-calls`` flag
-``__sanitizer_cov_trace_pc_indirect(void *callee)`` will be inserted on every indirect call.
-These callbacks are not implemented in the Sanitizer run-time and should be defined
-by the user. So, these flags do not require the other sanitizer to be used.
-This mechanism is used for fuzzing the Linux kernel (https://github.com/google/syzkaller)
-and can be used with `AFL <http://lcamtuf.coredump.cx/afl>`__.
+LLVM has a simple code coverage instrumentation built in (SanitizerCoverage).
+It inserts calls to user-defined functions on function-, basic-block-, and edge- levels.
+Default implementations of those callbacks are provided and implement
+simple coverage reporting and visualization,
+however if you need *just* coverage visualization you may want to use
+:doc:`SourceBasedCodeCoverage <SourceBasedCodeCoverage>` instead.
 
 Tracing PCs with guards
 =======================
@@ -217,7 +27,7 @@ on every edge:
 
 Every edge will have its own `guard_variable` (uint32_t).
 
-The compler will also insert a module constructor that will call
+The compler will also insert calls to a module constructor:
 
 .. code-block:: c++
 
@@ -226,7 +36,7 @@ The compler will also insert a module constructor that will call
    // more than once with the same values of start/stop.
    __sanitizer_cov_trace_pc_guard_init(uint32_t *start, uint32_t *stop);
 
-With `trace-pc-guards,indirect-calls`
+With an additional ``...=trace-pc,indirect-calls`` flag
 ``__sanitizer_cov_trace_pc_indirect(void *callee)`` will be inserted on every indirect call.
 
 The functions `__sanitizer_cov_trace_pc_*` should be defined by the user.
@@ -309,6 +119,75 @@ Example:
   guard: 0x71bcdc 4 PC 0x4ecdc7 in main trace-pc-guard-example.cc:4:17
   guard: 0x71bcd0 1 PC 0x4ecd20 in foo() trace-pc-guard-example.cc:2:14
 
+Tracing PCs
+===========
+
+With ``-fsanitize-coverage=trace-pc`` the compiler will insert
+``__sanitizer_cov_trace_pc()`` on every edge.
+With an additional ``...=trace-pc,indirect-calls`` flag
+``__sanitizer_cov_trace_pc_indirect(void *callee)`` will be inserted on every indirect call.
+These callbacks are not implemented in the Sanitizer run-time and should be defined
+by the user.
+This mechanism is used for fuzzing the Linux kernel
+(https://github.com/google/syzkaller).
+
+
+Instrumentation points
+======================
+Sanitizer Coverage offers different levels of instrumentation.
+
+* ``edge`` (default): edges are instrumented (see below).
+* ``bb``: basic blocks are instrumented.
+* ``func``: only the entry block of every function will be instrumented.
+
+Use these flags together with ``trace-pc-guard`` or ``trace-pc``,
+like this: ``-fsanitize-coverage=func,trace-pc-guard``.
+
+When ``edge`` or ``bb`` is used, some of the edges/blocks may still be left
+uninstrumented if such instrumentation is considered redundant.
+**TODO**: add a user-visible option to disable the optimization.
+
+
+Edge coverage
+-------------
+
+Consider this code:
+
+.. code-block:: c++
+
+    void foo(int *a) {
+      if (a)
+        *a = 0;
+    }
+
+It contains 3 basic blocks, let's name them A, B, C:
+
+.. code-block:: none
+
+    A
+    |\
+    | \
+    |  B
+    | /
+    |/
+    C
+
+If blocks A, B, and C are all covered we know for certain that the edges A=>B
+and B=>C were executed, but we still don't know if the edge A=>C was executed.
+Such edges of control flow graph are called
+`critical <http://en.wikipedia.org/wiki/Control_flow_graph#Special_edges>`_. The
+edge-level coverage simply splits all critical
+edges by introducing new dummy blocks and then instruments those blocks:
+
+.. code-block:: none
+
+    A
+    |\
+    | \
+    D  B
+    | /
+    |/
+    C
 
 Tracing data flow
 =================
@@ -349,50 +228,107 @@ the `LLVM GEP instructions <http://llvm.org/docs/GetElementPtr.html>`_
 
 
 This interface is a subject to change.
-The current implementation is not thread-safe and thus can be safely used only for single-threaded targets.
 
-Output directory
-================
+Default implementation
+======================
 
-By default, .sancov files are created in the current working directory.
-This can be changed with ``ASAN_OPTIONS=coverage_dir=/path``:
+The sanitizer run-time (AddressSanitizer, MemorySanitizer, etc) provide a
+default implementations of some of the coverage callbacks.
+You may use this implementation to dump the coverage on disk at the process
+exit.
+
+Example:
 
 .. code-block:: console
 
-    % ASAN_OPTIONS="coverage=1:coverage_dir=/tmp/cov" ./a.out foo
-    % ls -l /tmp/cov/*sancov
-    -rw-r----- 1 kcc eng 4 Nov 27 12:21 a.out.22673.sancov
-    -rw-r----- 1 kcc eng 8 Nov 27 12:21 a.out.22679.sancov
+    % cat -n cov.cc
+         1  #include <stdio.h>
+         2  __attribute__((noinline))
+         3  void foo() { printf("foo\n"); }
+         4
+         5  int main(int argc, char **argv) {
+         6    if (argc == 2)
+         7      foo();
+         8    printf("main\n");
+         9  }
+    % clang++ -g cov.cc -fsanitize=address -fsanitize-coverage=trace-pc-guard
+    % ASAN_OPTIONS=coverage=1 ./a.out; wc -c *.sancov
+    main
+    SanitizerCoverage: ./a.out.7312.sancov 2 PCs written
+    24 a.out.7312.sancov
+    % ASAN_OPTIONS=coverage=1 ./a.out foo ; wc -c *.sancov
+    foo
+    main
+    SanitizerCoverage: ./a.out.7316.sancov 3 PCs written
+    24 a.out.7312.sancov
+    32 a.out.7316.sancov
 
-Sudden death
-============
+Every time you run an executable instrumented with SanitizerCoverage
+one ``*.sancov`` file is created during the process shutdown.
+If the executable is dynamically linked against instrumented DSOs,
+one ``*.sancov`` file will be also created for every DSO.
 
-Normally, coverage data is collected in memory and saved to disk when the
-program exits (with an ``atexit()`` handler), when a SIGSEGV is caught, or when
-``__sanitizer_cov_dump()`` is called.
+Sancov data format
+------------------
 
-If the program ends with a signal that ASan does not handle (or can not handle
-at all, like SIGKILL), coverage data will be lost. This is a big problem on
-Android, where SIGKILL is a normal way of evicting applications from memory.
+The format of ``*.sancov`` files is very simple: the first 8 bytes is the magic,
+one of ``0xC0BFFFFFFFFFFF64`` and ``0xC0BFFFFFFFFFFF32``. The last byte of the
+magic defines the size of the following offsets. The rest of the data is the
+offsets in the corresponding binary/DSO that were executed during the run.
+
+Sancov Tool
+-----------
 
-With ``ASAN_OPTIONS=coverage=1:coverage_direct=1`` coverage data is written to a
-memory-mapped file as soon as it collected.
+An simple ``sancov`` tool is provided to process coverage files.
+The tool is part of LLVM project and is currently supported only on Linux.
+It can handle symbolization tasks autonomously without any extra support
+from the environment. You need to pass .sancov files (named 
+``<module_name>.<pid>.sancov`` and paths to all corresponding binary elf files. 
+Sancov matches these files using module names and binaries file names.
 
 .. code-block:: console
 
-    % ASAN_OPTIONS="coverage=1:coverage_direct=1" ./a.out
-    main
-    % ls
-    7036.sancov.map  7036.sancov.raw  a.out
-    % sancov.py rawunpack 7036.sancov.raw
-    sancov.py: reading map 7036.sancov.map
-    sancov.py: unpacking 7036.sancov.raw
-    writing 1 PCs to a.out.7036.sancov
-    % sancov.py print a.out.7036.sancov
-    sancov.py: read 1 PCs from a.out.7036.sancov
-    sancov.py: 1 files merged; 1 PCs total
-    0x4b2bae
-
-Note that on 64-bit platforms, this method writes 2x more data than the default,
-because it stores full PC values instead of 32-bit offsets.
+    USAGE: sancov [options] <action> (<binary file>|<.sancov file>)...
+
+    Action (required)
+      -print                    - Print coverage addresses
+      -covered-functions        - Print all covered functions.
+      -not-covered-functions    - Print all not covered functions.
+      -symbolize                - Symbolizes the report.
+
+    Options
+      -blacklist=<string>         - Blacklist file (sanitizer blacklist format).
+      -demangle                   - Print demangled function name.
+      -strip_path_prefix=<string> - Strip this prefix from file paths in reports
+
+
+Coverage Reports
+----------------
 
+**Experimental**
+
+``.sancov`` files do not contain enough information to generate a source-level
+coverage report. The missing information is contained
+in debug info of the binary. Thus the ``.sancov`` has to be symbolized
+to produce a ``.symcov`` file first:
+
+.. code-block:: console
+
+    sancov -symbolize my_program.123.sancov my_program > my_program.123.symcov
+
+The ``.symcov`` file can be browsed overlayed over the source code by
+running ``tools/sancov/coverage-report-server.py`` script that will start
+an HTTP server.
+
+Output directory
+----------------
+
+By default, .sancov files are created in the current working directory.
+This can be changed with ``ASAN_OPTIONS=coverage_dir=/path``:
+
+.. code-block:: console
+
+    % ASAN_OPTIONS="coverage=1:coverage_dir=/tmp/cov" ./a.out foo
+    % ls -l /tmp/cov/*sancov
+    -rw-r----- 1 kcc eng 4 Nov 27 12:21 a.out.22673.sancov
+    -rw-r----- 1 kcc eng 8 Nov 27 12:21 a.out.22679.sancov
diff --git a/include/clang-c/Index.h b/include/clang-c/Index.h
index 9acc9b75bffb..c50ac1b6d248 100644
--- a/include/clang-c/Index.h
+++ b/include/clang-c/Index.h
@@ -32,7 +32,7 @@
  * compatible, thus CINDEX_VERSION_MAJOR is expected to remain stable.
  */
 #define CINDEX_VERSION_MAJOR 0
-#define CINDEX_VERSION_MINOR 37
+#define CINDEX_VERSION_MINOR 38
 
 #define CINDEX_VERSION_ENCODE(major, minor) ( \
       ((major) * 10000)                       \
@@ -81,6 +81,12 @@ extern "C" {
 typedef void *CXIndex;
 
 /**
+ * \brief An opaque type representing target information for a given translation
+ * unit.
+ */
+typedef struct CXTargetInfoImpl *CXTargetInfo;
+
+/**
  * \brief A single translation unit, which resides in an index.
  */
 typedef struct CXTranslationUnitImpl *CXTranslationUnit;
@@ -1553,6 +1559,36 @@ CINDEX_LINKAGE CXTUResourceUsage clang_getCXTUResourceUsage(CXTranslationUnit TU
 CINDEX_LINKAGE void clang_disposeCXTUResourceUsage(CXTUResourceUsage usage);
 
 /**
+ * \brief Get target information for this translation unit.
+ *
+ * The CXTargetInfo object cannot outlive the CXTranslationUnit object.
+ */
+CINDEX_LINKAGE CXTargetInfo
+clang_getTranslationUnitTargetInfo(CXTranslationUnit CTUnit);
+
+/**
+ * \brief Destroy the CXTargetInfo object.
+ */
+CINDEX_LINKAGE void
+clang_TargetInfo_dispose(CXTargetInfo Info);
+
+/**
+ * \brief Get the normalized target triple as a string.
+ *
+ * Returns the empty string in case of any error.
+ */
+CINDEX_LINKAGE CXString
+clang_TargetInfo_getTriple(CXTargetInfo Info);
+
+/**
+ * \brief Get the pointer width of the target in bits.
+ *
+ * Returns -1 in case of error.
+ */
+CINDEX_LINKAGE int
+clang_TargetInfo_getPointerWidth(CXTargetInfo Info);
+
+/**
  * @}
  */
 
@@ -3975,8 +4011,8 @@ CINDEX_LINKAGE int clang_Cursor_getObjCSelectorIndex(CXCursor);
 CINDEX_LINKAGE int clang_Cursor_isDynamicCall(CXCursor C);
 
 /**
- * \brief Given a cursor pointing to an Objective-C message, returns the CXType
- * of the receiver.
+ * \brief Given a cursor pointing to an Objective-C message or property
+ * reference, or C++ method call, returns the CXType of the receiver.
  */
 CINDEX_LINKAGE CXType clang_Cursor_getReceiverType(CXCursor C);
 
diff --git a/include/clang/AST/ASTStructuralEquivalence.h b/include/clang/AST/ASTStructuralEquivalence.h
new file mode 100644
index 000000000000..770bb5763fbd
--- /dev/null
+++ b/include/clang/AST/ASTStructuralEquivalence.h
@@ -0,0 +1,101 @@
+//===--- ASTStructuralEquivalence.h - ---------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the StructuralEquivalenceContext class which checks for
+//  structural equivalence between types.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_ASTSTRUCTURALEQUIVALENCE_H
+#define LLVM_CLANG_AST_ASTSTRUCTURALEQUIVALENCE_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/Optional.h"
+#include <deque>
+
+namespace clang {
+
+class ASTContext;
+class Decl;
+class DiagnosticBuilder;
+class QualType;
+class RecordDecl;
+class SourceLocation;
+
+struct StructuralEquivalenceContext {
+  /// AST contexts for which we are checking structural equivalence.
+  ASTContext &FromCtx, &ToCtx;
+
+  /// The set of "tentative" equivalences between two canonical
+  /// declarations, mapping from a declaration in the first context to the
+  /// declaration in the second context that we believe to be equivalent.
+  llvm::DenseMap<Decl *, Decl *> TentativeEquivalences;
+
+  /// Queue of declarations in the first context whose equivalence
+  /// with a declaration in the second context still needs to be verified.
+  std::deque<Decl *> DeclsToCheck;
+
+  /// Declaration (from, to) pairs that are known not to be equivalent
+  /// (which we have already complained about).
+  llvm::DenseSet<std::pair<Decl *, Decl *>> &NonEquivalentDecls;
+
+  /// Whether we're being strict about the spelling of types when
+  /// unifying two types.
+  bool StrictTypeSpelling;
+
+  /// Whether warn or error on tag type mismatches.
+  bool ErrorOnTagTypeMismatch;
+
+  /// Whether to complain about failures.
+  bool Complain;
+
+  /// \c true if the last diagnostic came from ToCtx.
+  bool LastDiagFromC2;
+
+  StructuralEquivalenceContext(
+      ASTContext &FromCtx, ASTContext &ToCtx,
+      llvm::DenseSet<std::pair<Decl *, Decl *>> &NonEquivalentDecls,
+      bool StrictTypeSpelling = false, bool Complain = true)
+      : FromCtx(FromCtx), ToCtx(ToCtx), NonEquivalentDecls(NonEquivalentDecls),
+        StrictTypeSpelling(StrictTypeSpelling), Complain(Complain),
+        LastDiagFromC2(false) {}
+
+  DiagnosticBuilder Diag1(SourceLocation Loc, unsigned DiagID);
+  DiagnosticBuilder Diag2(SourceLocation Loc, unsigned DiagID);
+
+  /// Determine whether the two declarations are structurally
+  /// equivalent.
+  bool IsStructurallyEquivalent(Decl *D1, Decl *D2);
+
+  /// Determine whether the two types are structurally equivalent.
+  bool IsStructurallyEquivalent(QualType T1, QualType T2);
+
+  /// Find the index of the given anonymous struct/union within its
+  /// context.
+  ///
+  /// \returns Returns the index of this anonymous struct/union in its context,
+  /// including the next assigned index (if none of them match). Returns an
+  /// empty option if the context is not a record, i.e.. if the anonymous
+  /// struct/union is at namespace or block scope.
+  ///
+  /// FIXME: This is needed by ASTImporter and ASTStructureEquivalence. It
+  /// probably makes more sense in some other common place then here.
+  static llvm::Optional<unsigned>
+  findUntaggedStructOrUnionIndex(RecordDecl *Anon);
+
+private:
+  /// Finish checking all of the structural equivalences.
+  ///
+  /// \returns true if an error occurred, false otherwise.
+  bool Finish();
+};
+} // namespace clang
+
+#endif // LLVM_CLANG_AST_ASTSTRUCTURALEQUIVALENCE_H
diff --git a/include/clang/AST/DeclBase.h b/include/clang/AST/DeclBase.h
index c88cb6a8fd1e..15ac11a5a777 100644
--- a/include/clang/AST/DeclBase.h
+++ b/include/clang/AST/DeclBase.h
@@ -616,6 +616,14 @@ public:
   getAvailability(std::string *Message = nullptr,
                   VersionTuple EnclosingVersion = VersionTuple()) const;
 
+  /// \brief Retrieve the version of the target platform in which this
+  /// declaration was introduced.
+  ///
+  /// \returns An empty version tuple if this declaration has no 'introduced'
+  /// availability attributes, or the version tuple that's specified in the
+  /// attribute otherwise.
+  VersionTuple getVersionIntroduced() const;
+
   /// \brief Determine whether this declaration is marked 'deprecated'.
   ///
   /// \param Message If non-NULL and the declaration is deprecated,
diff --git a/include/clang/AST/Type.h b/include/clang/AST/Type.h
index bd30aad10f27..b1c2503c32e3 100644
--- a/include/clang/AST/Type.h
+++ b/include/clang/AST/Type.h
@@ -1396,7 +1396,7 @@ protected:
 
     /// Extra information which affects how the function is called, like
     /// regparm and the calling convention.
-    unsigned ExtInfo : 10;
+    unsigned ExtInfo : 11;
 
     /// Used only by FunctionProtoType, put here to pack with the
     /// other bitfields.
@@ -2941,19 +2941,23 @@ class FunctionType : public Type {
   // * AST read and write
   // * Codegen
   class ExtInfo {
-    // Feel free to rearrange or add bits, but if you go over 10,
+    // Feel free to rearrange or add bits, but if you go over 11,
     // you'll need to adjust both the Bits field below and
     // Type::FunctionTypeBitfields.
 
-    //   |  CC  |noreturn|produces|regparm|
-    //   |0 .. 4|   5    |    6   | 7 .. 9|
+    //   |  CC  |noreturn|produces|nocallersavedregs|regparm|
+    //   |0 .. 4|   5    |    6   |       7         |8 .. 10|
     //
     // regparm is either 0 (no regparm attribute) or the regparm value+1.
     enum { CallConvMask = 0x1F };
     enum { NoReturnMask = 0x20 };
     enum { ProducesResultMask = 0x40 };
-    enum { RegParmMask = ~(CallConvMask | NoReturnMask | ProducesResultMask),
-           RegParmOffset = 7 }; // Assumed to be the last field
+    enum { NoCallerSavedRegsMask = 0x80 };
+    enum {
+      RegParmMask = ~(CallConvMask | NoReturnMask | ProducesResultMask |
+                      NoCallerSavedRegsMask),
+      RegParmOffset = 8
+    }; // Assumed to be the last field
 
     uint16_t Bits;
 
@@ -2964,13 +2968,13 @@ class FunctionType : public Type {
    public:
     // Constructor with no defaults. Use this when you know that you
     // have all the elements (when reading an AST file for example).
-    ExtInfo(bool noReturn, bool hasRegParm, unsigned regParm, CallingConv cc,
-            bool producesResult) {
-      assert((!hasRegParm || regParm < 7) && "Invalid regparm value");
-      Bits = ((unsigned) cc) |
-             (noReturn ? NoReturnMask : 0) |
-             (producesResult ? ProducesResultMask : 0) |
-             (hasRegParm ? ((regParm + 1) << RegParmOffset) : 0);
+     ExtInfo(bool noReturn, bool hasRegParm, unsigned regParm, CallingConv cc,
+             bool producesResult, bool noCallerSavedRegs) {
+       assert((!hasRegParm || regParm < 7) && "Invalid regparm value");
+       Bits = ((unsigned)cc) | (noReturn ? NoReturnMask : 0) |
+              (producesResult ? ProducesResultMask : 0) |
+              (noCallerSavedRegs ? NoCallerSavedRegsMask : 0) |
+              (hasRegParm ? ((regParm + 1) << RegParmOffset) : 0);
     }
 
     // Constructor with all defaults. Use when for example creating a
@@ -2983,6 +2987,7 @@ class FunctionType : public Type {
 
     bool getNoReturn() const { return Bits & NoReturnMask; }
     bool getProducesResult() const { return Bits & ProducesResultMask; }
+    bool getNoCallerSavedRegs() const { return Bits & NoCallerSavedRegsMask; }
     bool getHasRegParm() const { return (Bits >> RegParmOffset) != 0; }
     unsigned getRegParm() const {
       unsigned RegParm = Bits >> RegParmOffset;
@@ -3016,6 +3021,13 @@ class FunctionType : public Type {
         return ExtInfo(Bits & ~ProducesResultMask);
     }
 
+    ExtInfo withNoCallerSavedRegs(bool noCallerSavedRegs) const {
+      if (noCallerSavedRegs)
+        return ExtInfo(Bits | NoCallerSavedRegsMask);
+      else
+        return ExtInfo(Bits & ~NoCallerSavedRegsMask);
+    }
+
     ExtInfo withRegParm(unsigned RegParm) const {
       assert(RegParm < 7 && "Invalid regparm value");
       return ExtInfo((Bits & ~RegParmMask) |
diff --git a/include/clang/Basic/Attr.td b/include/clang/Basic/Attr.td
index 44893fbd036c..04a948a6c46e 100644
--- a/include/clang/Basic/Attr.td
+++ b/include/clang/Basic/Attr.td
@@ -1931,6 +1931,12 @@ def AnyX86Interrupt : InheritableAttr, TargetSpecificAttr<TargetAnyX86> {
   let Documentation = [AnyX86InterruptDocs];
 }
 
+def AnyX86NoCallerSavedRegisters : InheritableAttr,
+                                   TargetSpecificAttr<TargetAnyX86> {
+  let Spellings = [GCC<"no_caller_saved_registers">];
+  let Documentation = [AnyX86NoCallerSavedRegistersDocs];
+}
+
 def X86ForceAlignArgPointer : InheritableAttr, TargetSpecificAttr<TargetX86> {
   let Spellings = [GNU<"force_align_arg_pointer">];
   // Technically, this appertains to a FunctionDecl, but the target-specific
diff --git a/include/clang/Basic/AttrDocs.td b/include/clang/Basic/AttrDocs.td
index 71cfe36a8fa4..be2a91515ae8 100644
--- a/include/clang/Basic/AttrDocs.td
+++ b/include/clang/Basic/AttrDocs.td
@@ -2657,6 +2657,40 @@ hardware design, touch the red zone.
   }];
 }
 
+def AnyX86NoCallerSavedRegistersDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+Use this attribute to indicate that the specified function has no
+caller-saved registers. That is, all registers are callee-saved except for
+registers used for passing parameters to the function or returning parameters
+from the function.
+The compiler saves and restores any modified registers that were not used for 
+passing or returning arguments to the function.
+
+The user can call functions specified with the 'no_caller_saved_registers'
+attribute from an interrupt handler without saving and restoring all
+call-clobbered registers.
+
+Note that 'no_caller_saved_registers' attribute is not a calling convention.
+In fact, it only overrides the decision of which registers should be saved by
+the caller, but not how the parameters are passed from the caller to the callee.
+
+For example:
+
+  .. code-block:: c
+
+    __attribute__ ((no_caller_saved_registers, fastcall))
+    void f (int arg1, int arg2) {
+      ...
+    }
+
+  In this case parameters 'arg1' and 'arg2' will be passed in registers.
+  In this case, on 32-bit x86 targets, the function 'f' will use ECX and EDX as
+  register parameters. However, it will not assume any scratch registers and
+  should save and restore any modified registers except for ECX and EDX.
+  }];
+}
+
 def SwiftCallDocs : Documentation {
   let Category = DocCatVariable;
   let Content = [{
diff --git a/include/clang/Basic/DiagnosticASTKinds.td b/include/clang/Basic/DiagnosticASTKinds.td
index 652d06278557..a07dbf631152 100644
--- a/include/clang/Basic/DiagnosticASTKinds.td
+++ b/include/clang/Basic/DiagnosticASTKinds.td
@@ -154,12 +154,14 @@ def note_constexpr_baa_insufficient_alignment : Note<
 def note_constexpr_baa_value_insufficient_alignment : Note<
   "value of the aligned pointer (%0) is not a multiple of the asserted %1 "
   "%plural{1:byte|:bytes}1">;
+def note_constexpr_array_unknown_bound_arithmetic : Note<
+  "cannot perform pointer arithmetic on pointer to array without constant bound">;
 
 def warn_integer_constant_overflow : Warning<
   "overflow in expression; result is %0 with type %1">,
   InGroup<DiagGroup<"integer-overflow">>;
 
-// This is a temporary diagnostic, and shall be removed once our 
+// This is a temporary diagnostic, and shall be removed once our
 // implementation is complete, and like the preceding constexpr notes belongs
 // in Sema.
 def note_unimplemented_constexpr_lambda_feature_ast : Note<
diff --git a/include/clang/Basic/DiagnosticDriverKinds.td b/include/clang/Basic/DiagnosticDriverKinds.td
index 3980805ef9bc..3833f0f28f05 100644
--- a/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/include/clang/Basic/DiagnosticDriverKinds.td
@@ -233,7 +233,9 @@ def note_drv_t_option_is_global : Note<
   "The last /TC or /TP option takes precedence over earlier instances">;
 def note_drv_address_sanitizer_debug_runtime : Note<
   "AddressSanitizer doesn't support linking with debug runtime libraries yet">;
-def note_drv_use_standard : Note<"use '%0' for '%1' standard">;
+def note_drv_use_standard : Note<"use '%0'"
+  "%select{| or '%3'|, '%3', or '%4'|, '%3', '%4', or '%5'}2 "
+  "for '%1' standard">;
 
 def err_analyzer_config_no_value : Error<
   "analyzer-config option '%0' has a key but no value">;
diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index 4cde1c81fd4d..05e03fab40fa 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -890,6 +890,7 @@ def BackendOptimizationRemarkAnalysis : DiagGroup<"pass-analysis">;
 def BackendOptimizationFailure : DiagGroup<"pass-failed">;
 
 // Instrumentation based profiling warnings.
+def ProfileInstrMissing : DiagGroup<"profile-instr-missing">;
 def ProfileInstrOutOfDate : DiagGroup<"profile-instr-out-of-date">;
 def ProfileInstrUnprofiled : DiagGroup<"profile-instr-unprofiled">;
 
diff --git a/include/clang/Basic/DiagnosticLexKinds.td b/include/clang/Basic/DiagnosticLexKinds.td
index cf33d5fba3d7..cd284e94303b 100644
--- a/include/clang/Basic/DiagnosticLexKinds.td
+++ b/include/clang/Basic/DiagnosticLexKinds.td
@@ -475,6 +475,8 @@ def warn_pragma_pop_macro_no_push : Warning<
 def warn_pragma_message : Warning<"%0">,
    InGroup<PoundPragmaMessage>, DefaultWarnNoWerror;
 def err_pragma_message : Error<"%0">;
+def err_pragma_module_import_expected_module_name : Error<
+  "expected %select{identifier in|'.' or end of directive after}0 module name">;
 def warn_pragma_ignored : Warning<"unknown pragma ignored">,
    InGroup<UnknownPragmas>, DefaultIgnore;
 def ext_stdc_pragma_ignored : ExtWarn<"unknown pragma in STDC namespace">,
@@ -503,7 +505,7 @@ def warn_pragma_diagnostic_invalid_token :
    InGroup<UnknownPragmas>;
 def warn_pragma_diagnostic_unknown_warning :
    ExtWarn<"unknown warning group '%0', ignored">,
-   InGroup<UnknownPragmas>;
+   InGroup<UnknownWarningOption>;
 // - #pragma __debug
 def warn_pragma_debug_unexpected_command : Warning<
   "unexpected debug command '%0'">, InGroup<IgnoredPragmas>;
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index b5fed1f218b6..d62ab098364d 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1180,6 +1180,10 @@ def err_objc_kindof_nonobject : Error<
 def err_objc_kindof_wrong_position : Error<
   "'__kindof' type specifier must precede the declarator">;
 
+def err_objc_method_unsupported_param_ret_type : Error<
+  "%0 %select{parameter|return}1 type is unsupported; "
+  "support for vector types for this target is introduced in %2">;
+
 // C++ declarations
 def err_static_assert_expression_is_not_constant : Error<
   "static_assert expression is not an integral constant expression">;
@@ -2819,6 +2823,9 @@ def err_regparm_mismatch : Error<"function declared with regparm(%0) "
 def err_returns_retained_mismatch : Error<
   "function declared with the ns_returns_retained attribute "
   "was previously declared without the ns_returns_retained attribute">;
+def err_function_attribute_mismatch : Error<
+  "function declared with %0 attribute "
+  "was previously declared without the %0 attribute">;
 def err_objc_precise_lifetime_bad_type : Error<
   "objc_precise_lifetime only applies to retainable types; type here is %0">;
 def warn_objc_precise_lifetime_meaningless : Error<
@@ -8931,8 +8938,13 @@ def warn_not_a_doxygen_trailing_member_comment : Warning<
 let CategoryName = "Instrumentation Issue" in {
 def warn_profile_data_out_of_date : Warning<
   "profile data may be out of date: of %0 function%s0, %1 %plural{1:has|:have}1"
-  " no data and %2 %plural{1:has|:have}2 mismatched data that will be ignored">,
+  " mismatched data that will be ignored">,
   InGroup<ProfileInstrOutOfDate>;
+def warn_profile_data_missing : Warning<
+  "profile data may be incomplete: of %0 function%s0, %1 %plural{1:has|:have}1"
+  " no data">,
+  InGroup<ProfileInstrMissing>,
+  DefaultIgnore;
 def warn_profile_data_unprofiled : Warning<
   "no profile data available for file \"%0\"">,
   InGroup<ProfileInstrUnprofiled>;
diff --git a/include/clang/Basic/LangOptions.def b/include/clang/Basic/LangOptions.def
index 6ae34a89fe28..60c8a68cd2e9 100644
--- a/include/clang/Basic/LangOptions.def
+++ b/include/clang/Basic/LangOptions.def
@@ -266,7 +266,8 @@ LANGOPT(SanitizeAddressFieldPadding, 2, 0, "controls how aggressive is ASan "
 
 LANGOPT(XRayInstrument, 1, 0, "controls whether to do XRay instrumentation")
 
-LANGOPT(AllowEditorPlaceholders, 1, 0, "allow editor placeholders in source")
+BENIGN_LANGOPT(AllowEditorPlaceholders, 1, 0,
+               "allow editor placeholders in source")
 
 #undef LANGOPT
 #undef COMPATIBLE_LANGOPT
diff --git a/include/clang/CodeGen/CGFunctionInfo.h b/include/clang/CodeGen/CGFunctionInfo.h
index 2703f299d217..d1f05124d5e5 100644
--- a/include/clang/CodeGen/CGFunctionInfo.h
+++ b/include/clang/CodeGen/CGFunctionInfo.h
@@ -461,7 +461,7 @@ class CGFunctionInfo final
   unsigned EffectiveCallingConvention : 8;
 
   /// The clang::CallingConv that this was originally created with.
-  unsigned ASTCallingConvention : 8;
+  unsigned ASTCallingConvention : 7;
 
   /// Whether this is an instance method.
   unsigned InstanceMethod : 1;
@@ -475,6 +475,9 @@ class CGFunctionInfo final
   /// Whether this function is returns-retained.
   unsigned ReturnsRetained : 1;
 
+  /// Whether this function saved caller registers.
+  unsigned NoCallerSavedRegs : 1;
+
   /// How many arguments to pass inreg.
   unsigned HasRegParm : 1;
   unsigned RegParm : 3;
@@ -560,6 +563,9 @@ public:
   /// is not always reliable for call sites.
   bool isReturnsRetained() const { return ReturnsRetained; }
 
+  /// Whether this function no longer saves caller registers.
+  bool isNoCallerSavedRegs() const { return NoCallerSavedRegs; }
+
   /// getASTCallingConvention() - Return the AST-specified calling
   /// convention.
   CallingConv getASTCallingConvention() const {
@@ -583,10 +589,9 @@ public:
   unsigned getRegParm() const { return RegParm; }
 
   FunctionType::ExtInfo getExtInfo() const {
-    return FunctionType::ExtInfo(isNoReturn(),
-                                 getHasRegParm(), getRegParm(),
-                                 getASTCallingConvention(),
-                                 isReturnsRetained());
+    return FunctionType::ExtInfo(isNoReturn(), getHasRegParm(), getRegParm(),
+                                 getASTCallingConvention(), isReturnsRetained(),
+                                 isNoCallerSavedRegs());
   }
 
   CanQualType getReturnType() const { return getArgsBuffer()[0].type; }
@@ -623,6 +628,7 @@ public:
     ID.AddBoolean(ChainCall);
     ID.AddBoolean(NoReturn);
     ID.AddBoolean(ReturnsRetained);
+    ID.AddBoolean(NoCallerSavedRegs);
     ID.AddBoolean(HasRegParm);
     ID.AddInteger(RegParm);
     ID.AddInteger(Required.getOpaqueData());
@@ -648,6 +654,7 @@ public:
     ID.AddBoolean(ChainCall);
     ID.AddBoolean(info.getNoReturn());
     ID.AddBoolean(info.getProducesResult());
+    ID.AddBoolean(info.getNoCallerSavedRegs());
     ID.AddBoolean(info.getHasRegParm());
     ID.AddInteger(info.getRegParm());
     ID.AddInteger(required.getOpaqueData());
diff --git a/include/clang/Driver/CLCompatOptions.td b/include/clang/Driver/CLCompatOptions.td
index 61902653e210..d0d9c679de7a 100644
--- a/include/clang/Driver/CLCompatOptions.td
+++ b/include/clang/Driver/CLCompatOptions.td
@@ -61,6 +61,8 @@ def _SLASH_Brepro_ : CLFlag<"Brepro-">,
 def _SLASH_C : CLFlag<"C">,
   HelpText<"Don't discard comments when preprocessing">, Alias<C>;
 def _SLASH_c : CLFlag<"c">, HelpText<"Compile only">, Alias<c>;
+def _SLASH_d1reportAllClassLayout : CLFlag<"d1reportAllClassLayout">,
+  HelpText<"Dump record layout information">, Alias<fdump_record_layouts>;
 def _SLASH_D : CLJoinedOrSeparate<"D">, HelpText<"Define macro">,
   MetaVarName<"<macro[=value]>">, Alias<D>;
 def _SLASH_E : CLFlag<"E">, HelpText<"Preprocess to stdout">, Alias<E>;
diff --git a/include/clang/Edit/EditedSource.h b/include/clang/Edit/EditedSource.h
index b6ec8b8f06e2..b082e4e0a3df 100644
--- a/include/clang/Edit/EditedSource.h
+++ b/include/clang/Edit/EditedSource.h
@@ -65,7 +65,7 @@ public:
 
   bool commit(const Commit &commit);
   
-  void applyRewrites(EditsReceiver &receiver);
+  void applyRewrites(EditsReceiver &receiver, bool adjustRemovals = true);
   void clearRewrites();
 
   StringRef copyString(StringRef str) { return str.copy(StrAlloc); }
diff --git a/include/clang/Frontend/FrontendActions.h b/include/clang/Frontend/FrontendActions.h
index 778b40b15df7..cb4498514955 100644
--- a/include/clang/Frontend/FrontendActions.h
+++ b/include/clang/Frontend/FrontendActions.h
@@ -99,8 +99,6 @@ class GenerateModuleAction : public ASTFrontendAction {
   CreateOutputFile(CompilerInstance &CI, StringRef InFile) = 0;
 
 protected:
-  bool BeginSourceFileAction(CompilerInstance &CI, StringRef Filename) override;
-
   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
                                                  StringRef InFile) override;
 
@@ -112,20 +110,11 @@ protected:
 };
 
 class GenerateModuleFromModuleMapAction : public GenerateModuleAction {
-  clang::Module *Module = nullptr;
-  const FileEntry *ModuleMapForUniquing = nullptr;
-  bool IsSystem = false;
-
 private:
   bool BeginSourceFileAction(CompilerInstance &CI, StringRef Filename) override;
 
   std::unique_ptr<raw_pwrite_stream>
   CreateOutputFile(CompilerInstance &CI, StringRef InFile) override;
-
-public:
-  GenerateModuleFromModuleMapAction() {}
-  GenerateModuleFromModuleMapAction(const FileEntry *ModuleMap, bool IsSystem)
-      : ModuleMapForUniquing(ModuleMap), IsSystem(IsSystem) {}
 };
 
 class GenerateModuleInterfaceAction : public GenerateModuleAction {
diff --git a/include/clang/Frontend/FrontendOptions.h b/include/clang/Frontend/FrontendOptions.h
index 4fd0f82a3ad2..36c046891b47 100644
--- a/include/clang/Frontend/FrontendOptions.h
+++ b/include/clang/Frontend/FrontendOptions.h
@@ -23,6 +23,7 @@ class MemoryBuffer;
 }
 
 namespace clang {
+class FileEntry;
 
 namespace frontend {
   enum ActionKind {
@@ -62,25 +63,65 @@ namespace frontend {
   };
 }
 
-enum InputKind {
-  IK_None,
-  IK_Asm,
-  IK_C,
-  IK_CXX,
-  IK_ObjC,
-  IK_ObjCXX,
-  IK_PreprocessedC,
-  IK_PreprocessedCXX,
-  IK_PreprocessedObjC,
-  IK_PreprocessedObjCXX,
-  IK_OpenCL,
-  IK_CUDA,
-  IK_PreprocessedCuda,
-  IK_RenderScript,
-  IK_AST,
-  IK_LLVM_IR
-};
+/// The kind of a file that we've been handed as an input.
+class InputKind {
+private:
+  unsigned Lang : 4;
+  unsigned Fmt : 3;
+  unsigned Preprocessed : 1;
+
+public:
+  /// The language for the input, used to select and validate the language
+  /// standard and possible actions.
+  enum Language {
+    Unknown,
+
+    /// Assembly: we accept this only so that we can preprocess it.
+    Asm,
+
+    /// LLVM IR: we accept this so that we can run the optimizer on it,
+    /// and compile it to assembly or object code.
+    LLVM_IR,
+
+    ///@{ Languages that the frontend can parse and compile.
+    C,
+    CXX,
+    ObjC,
+    ObjCXX,
+    OpenCL,
+    CUDA,
+    RenderScript,
+    ///@}
+  };
+
+  /// The input file format.
+  enum Format {
+    Source,
+    ModuleMap,
+    Precompiled
+  };
+
+  constexpr InputKind(Language L = Unknown, Format F = Source,
+                      bool PP = false)
+      : Lang(L), Fmt(F), Preprocessed(PP) {}
+
+  Language getLanguage() const { return static_cast<Language>(Lang); }
+  Format getFormat() const { return static_cast<Format>(Fmt); }
+  bool isPreprocessed() const { return Preprocessed; }
 
+  /// Is the input kind fully-unknown?
+  bool isUnknown() const { return Lang == Unknown && Fmt == Source; }
+
+  /// Is the language of the input some dialect of Objective-C?
+  bool isObjectiveC() const { return Lang == ObjC || Lang == ObjCXX; }
+
+  InputKind getPreprocessed() const {
+    return InputKind(getLanguage(), getFormat(), true);
+  }
+  InputKind withFormat(Format F) const {
+    return InputKind(getLanguage(), F, isPreprocessed());
+  }
+};
 
 /// \brief An input file for the front end.
 class FrontendInputFile {
@@ -96,7 +137,7 @@ class FrontendInputFile {
   bool IsSystem;
 
 public:
-  FrontendInputFile() : Buffer(nullptr), Kind(IK_None), IsSystem(false) { }
+  FrontendInputFile() : Buffer(nullptr), Kind(), IsSystem(false) { }
   FrontendInputFile(StringRef File, InputKind Kind, bool IsSystem = false)
     : File(File.str()), Buffer(nullptr), Kind(Kind), IsSystem(IsSystem) { }
   FrontendInputFile(llvm::MemoryBuffer *buffer, InputKind Kind,
@@ -109,13 +150,7 @@ public:
   bool isEmpty() const { return File.empty() && Buffer == nullptr; }
   bool isFile() const { return !isBuffer(); }
   bool isBuffer() const { return Buffer != nullptr; }
-  bool isPreprocessed() const {
-    return Kind == IK_PreprocessedC ||
-           Kind == IK_PreprocessedCXX ||
-           Kind == IK_PreprocessedObjC ||
-           Kind == IK_PreprocessedObjCXX ||
-           Kind == IK_PreprocessedCuda;
-  }
+  bool isPreprocessed() const { return Kind.isPreprocessed(); }
 
   StringRef getFile() const {
     assert(isFile());
@@ -224,6 +259,10 @@ public:
   /// The input files and their types.
   std::vector<FrontendInputFile> Inputs;
 
+  /// When the input is a module map, the original module map file from which
+  /// that map was inferred, if any (for umbrella modules).
+  std::string OriginalModuleMap;
+
   /// The output file, if any.
   std::string OutputFile;
 
@@ -299,10 +338,10 @@ public:
   {}
 
   /// getInputKindForExtension - Return the appropriate input kind for a file
-  /// extension. For example, "c" would return IK_C.
+  /// extension. For example, "c" would return InputKind::C.
   ///
-  /// \return The input kind for the extension, or IK_None if the extension is
-  /// not recognized.
+  /// \return The input kind for the extension, or InputKind::Unknown if the
+  /// extension is not recognized.
   static InputKind getInputKindForExtension(StringRef Extension);
 };
 
diff --git a/include/clang/Frontend/LangStandard.h b/include/clang/Frontend/LangStandard.h
index 5ead90f00721..ec32aa8d161f 100644
--- a/include/clang/Frontend/LangStandard.h
+++ b/include/clang/Frontend/LangStandard.h
@@ -11,6 +11,7 @@
 #define LLVM_CLANG_FRONTEND_LANGSTANDARD_H
 
 #include "clang/Basic/LLVM.h"
+#include "clang/Frontend/FrontendOptions.h"
 #include "llvm/ADT/StringRef.h"
 
 namespace clang {
@@ -19,18 +20,17 @@ namespace frontend {
 
 enum LangFeatures {
   LineComment = (1 << 0),
-  C89 = (1 << 1),
-  C99 = (1 << 2),
-  C11 = (1 << 3),
-  CPlusPlus = (1 << 4),
-  CPlusPlus11 = (1 << 5),
-  CPlusPlus14 = (1 << 6),
-  CPlusPlus1z = (1 << 7),
-  Digraphs = (1 << 8),
-  GNUMode = (1 << 9),
-  HexFloat = (1 << 10),
-  ImplicitInt = (1 << 11),
-  OpenCL = (1 << 12)
+  C99 = (1 << 1),
+  C11 = (1 << 2),
+  CPlusPlus = (1 << 3),
+  CPlusPlus11 = (1 << 4),
+  CPlusPlus14 = (1 << 5),
+  CPlusPlus1z = (1 << 6),
+  Digraphs = (1 << 7),
+  GNUMode = (1 << 8),
+  HexFloat = (1 << 9),
+  ImplicitInt = (1 << 10),
+  OpenCL = (1 << 11)
 };
 
 }
@@ -39,7 +39,7 @@ enum LangFeatures {
 /// standard.
 struct LangStandard {
   enum Kind {
-#define LANGSTANDARD(id, name, desc, features) \
+#define LANGSTANDARD(id, name, lang, desc, features) \
     lang_##id,
 #include "clang/Frontend/LangStandards.def"
     lang_unspecified
@@ -48,6 +48,7 @@ struct LangStandard {
   const char *ShortName;
   const char *Description;
   unsigned Flags;
+  InputKind::Language Language;
 
 public:
   /// getName - Get the name of this standard.
@@ -56,12 +57,12 @@ public:
   /// getDescription - Get the description of this standard.
   const char *getDescription() const { return Description; }
 
+  /// Get the language that this standard describes.
+  InputKind::Language getLanguage() const { return Language; }
+
   /// Language supports '//' comments.
   bool hasLineComments() const { return Flags & frontend::LineComment; }
 
-  /// isC89 - Language is a superset of C89.
-  bool isC89() const { return Flags & frontend::C89; }
-
   /// isC99 - Language is a superset of C99.
   bool isC99() const { return Flags & frontend::C99; }
 
diff --git a/include/clang/Frontend/LangStandards.def b/include/clang/Frontend/LangStandards.def
index 425ac84bf6ff..1d214fd2a2be 100644
--- a/include/clang/Frontend/LangStandards.def
+++ b/include/clang/Frontend/LangStandards.def
@@ -11,10 +11,11 @@
 #error "LANGSTANDARD must be defined before including this file"
 #endif
 
-/// LANGSTANDARD(IDENT, NAME, DESC, FEATURES)
+/// LANGSTANDARD(IDENT, NAME, LANG, DESC, FEATURES)
 ///
 /// \param IDENT - The name of the standard as a C++ identifier.
 /// \param NAME - The name of the standard.
+/// \param LANG - The InputKind::Language for which this is a standard.
 /// \param DESC - A short description of the standard.
 /// \param FEATURES - The standard features as flags, these are enums from the
 /// clang::frontend namespace, which is assumed to be be available.
@@ -23,146 +24,126 @@
 /// \param IDENT - The name of the standard as a C++ identifier.
 /// \param ALIAS - The alias of the standard.
 
+/// LANGSTANDARD_ALIAS_DEPR(IDENT, ALIAS)
+/// Same as LANGSTANDARD_ALIAS, but for a deprecated alias.
+
 #ifndef LANGSTANDARD_ALIAS
 #define LANGSTANDARD_ALIAS(IDENT, ALIAS)
 #endif
 
+#ifndef LANGSTANDARD_ALIAS_DEPR
+#define LANGSTANDARD_ALIAS_DEPR(IDENT, ALIAS) LANGSTANDARD_ALIAS(IDENT, ALIAS)
+#endif
+
 // C89-ish modes.
 LANGSTANDARD(c89, "c89",
-             "ISO C 1990",
-             C89 | ImplicitInt)
-LANGSTANDARD(c90, "c90",
-             "ISO C 1990",
-             C89 | ImplicitInt)
-LANGSTANDARD(iso9899_1990, "iso9899:1990",
-             "ISO C 1990",
-             C89 | ImplicitInt)
+             C, "ISO C 1990",
+             ImplicitInt)
+LANGSTANDARD_ALIAS(c89, "c90")
+LANGSTANDARD_ALIAS(c89, "iso9899:1990")
 
 LANGSTANDARD(c94, "iso9899:199409",
-             "ISO C 1990 with amendment 1",
-             C89 | Digraphs | ImplicitInt)
+             C, "ISO C 1990 with amendment 1",
+             Digraphs | ImplicitInt)
 
 LANGSTANDARD(gnu89, "gnu89",
-             "ISO C 1990 with GNU extensions",
-             LineComment | C89 | Digraphs | GNUMode | ImplicitInt)
-LANGSTANDARD(gnu90, "gnu90",
-             "ISO C 1990 with GNU extensions",
-             LineComment | C89 | Digraphs | GNUMode | ImplicitInt)
+             C, "ISO C 1990 with GNU extensions",
+             LineComment | Digraphs | GNUMode | ImplicitInt)
+LANGSTANDARD_ALIAS(gnu89, "gnu90")
 
 // C99-ish modes
 LANGSTANDARD(c99, "c99",
-             "ISO C 1999",
-             LineComment | C99 | Digraphs | HexFloat)
-LANGSTANDARD(c9x, "c9x",
-             "ISO C 1999",
-             LineComment | C99 | Digraphs | HexFloat)
-LANGSTANDARD(iso9899_1999,
-             "iso9899:1999", "ISO C 1999",
-             LineComment | C99 | Digraphs | HexFloat)
-LANGSTANDARD(iso9899_199x,
-             "iso9899:199x", "ISO C 1999",
+             C, "ISO C 1999",
              LineComment | C99 | Digraphs | HexFloat)
+LANGSTANDARD_ALIAS(c99, "iso9899:1999")
+LANGSTANDARD_ALIAS_DEPR(c99, "c9x")
+LANGSTANDARD_ALIAS_DEPR(c99, "iso9899:199x")
 
 LANGSTANDARD(gnu99, "gnu99",
-             "ISO C 1999 with GNU extensions",
-             LineComment | C99 | Digraphs | GNUMode | HexFloat)
-LANGSTANDARD(gnu9x, "gnu9x",
-             "ISO C 1999 with GNU extensions",
+             C, "ISO C 1999 with GNU extensions",
              LineComment | C99 | Digraphs | GNUMode | HexFloat)
+LANGSTANDARD_ALIAS_DEPR(gnu99, "gnu9x")
 
 // C11 modes
 LANGSTANDARD(c11, "c11",
-             "ISO C 2011",
-             LineComment | C99 | C11 | Digraphs | HexFloat)
-LANGSTANDARD(c1x, "c1x",
-             "ISO C 2011",
-             LineComment | C99 | C11 | Digraphs | HexFloat)
-LANGSTANDARD(iso9899_2011,
-             "iso9899:2011", "ISO C 2011",
-             LineComment | C99 | C11 | Digraphs | HexFloat)
-LANGSTANDARD(iso9899_201x,
-             "iso9899:201x", "ISO C 2011",
+             C, "ISO C 2011",
              LineComment | C99 | C11 | Digraphs | HexFloat)
+LANGSTANDARD_ALIAS(c11, "iso9899:2011")
+LANGSTANDARD_ALIAS_DEPR(c11, "c1x")
+LANGSTANDARD_ALIAS_DEPR(c11, "iso9899:201x")
 
 LANGSTANDARD(gnu11, "gnu11",
-             "ISO C 2011 with GNU extensions",
-             LineComment | C99 | C11 | Digraphs | GNUMode | HexFloat)
-LANGSTANDARD(gnu1x, "gnu1x",
-             "ISO C 2011 with GNU extensions",
+             C, "ISO C 2011 with GNU extensions",
              LineComment | C99 | C11 | Digraphs | GNUMode | HexFloat)
+LANGSTANDARD_ALIAS_DEPR(gnu11, "gnu1x")
 
 // C++ modes
 LANGSTANDARD(cxx98, "c++98",
-             "ISO C++ 1998 with amendments",
-             LineComment | CPlusPlus | Digraphs)
-LANGSTANDARD(cxx03, "c++03",
-             "ISO C++ 1998 with amendments",
+             CXX, "ISO C++ 1998 with amendments",
              LineComment | CPlusPlus | Digraphs)
+LANGSTANDARD_ALIAS(cxx98, "c++03")
+
 LANGSTANDARD(gnucxx98, "gnu++98",
-             "ISO C++ 1998 with amendments and GNU extensions",
+             CXX, "ISO C++ 1998 with amendments and GNU extensions",
              LineComment | CPlusPlus | Digraphs | GNUMode)
+LANGSTANDARD_ALIAS(gnucxx98, "gnu++03")
 
-LANGSTANDARD(cxx0x, "c++0x",
-             "ISO C++ 2011 with amendments",
-             LineComment | CPlusPlus | CPlusPlus11 | Digraphs)
 LANGSTANDARD(cxx11, "c++11",
-             "ISO C++ 2011 with amendments",
+             CXX, "ISO C++ 2011 with amendments",
              LineComment | CPlusPlus | CPlusPlus11 | Digraphs)
-LANGSTANDARD(gnucxx0x, "gnu++0x",
-             "ISO C++ 2011 with amendments and GNU extensions",
-             LineComment | CPlusPlus | CPlusPlus11 | Digraphs | GNUMode)
-LANGSTANDARD(gnucxx11, "gnu++11",
+LANGSTANDARD_ALIAS_DEPR(cxx11, "c++0x")
+
+LANGSTANDARD(gnucxx11, "gnu++11", CXX,
              "ISO C++ 2011 with amendments and GNU extensions",
              LineComment | CPlusPlus | CPlusPlus11 | Digraphs | GNUMode)
+LANGSTANDARD_ALIAS_DEPR(gnucxx11, "gnu++0x")
 
-LANGSTANDARD(cxx1y, "c++1y",
-             "ISO C++ 2014 with amendments",
-             LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | Digraphs)
 LANGSTANDARD(cxx14, "c++14",
-             "ISO C++ 2014 with amendments",
+             CXX, "ISO C++ 2014 with amendments",
              LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | Digraphs)
-LANGSTANDARD(gnucxx1y, "gnu++1y",
-             "ISO C++ 2014 with amendments and GNU extensions",
-             LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | Digraphs |
-             GNUMode)
+LANGSTANDARD_ALIAS_DEPR(cxx14, "c++1y")
+
 LANGSTANDARD(gnucxx14, "gnu++14",
-             "ISO C++ 2014 with amendments and GNU extensions",
+             CXX, "ISO C++ 2014 with amendments and GNU extensions",
              LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | Digraphs |
              GNUMode)
+LANGSTANDARD_ALIAS_DEPR(gnucxx14, "gnu++1y")
 
 LANGSTANDARD(cxx1z, "c++1z",
-             "Working draft for ISO C++ 2017",
+             CXX, "Working draft for ISO C++ 2017",
              LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | CPlusPlus1z |
              Digraphs | HexFloat)
+
 LANGSTANDARD(gnucxx1z, "gnu++1z",
-             "Working draft for ISO C++ 2017 with GNU extensions",
+             CXX, "Working draft for ISO C++ 2017 with GNU extensions",
              LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | CPlusPlus1z |
              Digraphs | HexFloat | GNUMode)
 
 // OpenCL
-LANGSTANDARD(opencl, "cl",
-             "OpenCL 1.0",
+LANGSTANDARD(opencl10, "cl1.0",
+             OpenCL, "OpenCL 1.0",
              LineComment | C99 | Digraphs | HexFloat | OpenCL)
+LANGSTANDARD_ALIAS_DEPR(opencl10, "cl")
+
 LANGSTANDARD(opencl11, "cl1.1",
-             "OpenCL 1.1",
+             OpenCL, "OpenCL 1.1",
              LineComment | C99 | Digraphs | HexFloat | OpenCL)
 LANGSTANDARD(opencl12, "cl1.2",
-             "OpenCL 1.2",
+             OpenCL, "OpenCL 1.2",
              LineComment | C99 | Digraphs | HexFloat | OpenCL)
 LANGSTANDARD(opencl20, "cl2.0",
-             "OpenCL 2.0",
+             OpenCL, "OpenCL 2.0",
              LineComment | C99 | Digraphs | HexFloat | OpenCL)
 
-LANGSTANDARD_ALIAS(opencl, "CL")
-LANGSTANDARD_ALIAS(opencl11, "CL1.1")
-LANGSTANDARD_ALIAS(opencl12, "CL1.2")
-LANGSTANDARD_ALIAS(opencl20, "CL2.0")
+LANGSTANDARD_ALIAS_DEPR(opencl10, "CL")
+LANGSTANDARD_ALIAS_DEPR(opencl11, "CL1.1")
+LANGSTANDARD_ALIAS_DEPR(opencl12, "CL1.2")
+LANGSTANDARD_ALIAS_DEPR(opencl20, "CL2.0")
 
 // CUDA
-LANGSTANDARD(cuda, "cuda",
-             "NVIDIA CUDA(tm)",
+LANGSTANDARD(cuda, "cuda", CUDA, "NVIDIA CUDA(tm)",
              LineComment | CPlusPlus | Digraphs)
 
 #undef LANGSTANDARD
 #undef LANGSTANDARD_ALIAS
-
+#undef LANGSTANDARD_ALIAS_DEPR
diff --git a/include/clang/Lex/HeaderSearch.h b/include/clang/Lex/HeaderSearch.h
index 51983b9ab5d8..64c6f2a03f2b 100644
--- a/include/clang/Lex/HeaderSearch.h
+++ b/include/clang/Lex/HeaderSearch.h
@@ -375,13 +375,16 @@ public:
   /// \param SuggestedModule If non-null, and the file found is semantically
   /// part of a known module, this will be set to the module that should
   /// be imported instead of preprocessing/parsing the file found.
+  ///
+  /// \param IsMapped If non-null, and the search involved header maps, set to
+  /// true.
   const FileEntry *LookupFile(
       StringRef Filename, SourceLocation IncludeLoc, bool isAngled,
       const DirectoryLookup *FromDir, const DirectoryLookup *&CurDir,
       ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers,
       SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
       Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
-      bool SkipCache = false, bool BuildSystemModule = false);
+      bool *IsMapped, bool SkipCache = false, bool BuildSystemModule = false);
 
   /// \brief Look up a subframework for the specified \#include file.
   ///
diff --git a/include/clang/Lex/MacroInfo.h b/include/clang/Lex/MacroInfo.h
index 6cc3b0bb26f2..44b7b2e4a474 100644
--- a/include/clang/Lex/MacroInfo.h
+++ b/include/clang/Lex/MacroInfo.h
@@ -126,7 +126,7 @@ public:
   SourceLocation getDefinitionEndLoc() const { return EndLocation; }
 
   /// \brief Get length in characters of the macro definition.
-  unsigned getDefinitionLength(SourceManager &SM) const {
+  unsigned getDefinitionLength(const SourceManager &SM) const {
     if (IsDefinitionLengthCached)
       return DefinitionLength;
     return getDefinitionLengthSlow(SM);
@@ -285,7 +285,7 @@ public:
   void dump() const;
 
 private:
-  unsigned getDefinitionLengthSlow(SourceManager &SM) const;
+  unsigned getDefinitionLengthSlow(const SourceManager &SM) const;
 
   void setOwningModuleID(unsigned ID) {
     assert(isFromASTFile());
diff --git a/include/clang/Lex/PPCallbacks.h b/include/clang/Lex/PPCallbacks.h
index 2d027f314b5f..81c3bd7d14ec 100644
--- a/include/clang/Lex/PPCallbacks.h
+++ b/include/clang/Lex/PPCallbacks.h
@@ -247,10 +247,14 @@ public:
   }
 
   /// \brief Hook called whenever a macro \#undef is seen.
+  /// \param MacroNameTok The active Token
+  /// \param MD A MacroDefinition for the named macro.
+  /// \param Undef New MacroDirective if the macro was defined, null otherwise.
   ///
   /// MD is released immediately following this callback.
   virtual void MacroUndefined(const Token &MacroNameTok,
-                              const MacroDefinition &MD) {
+                              const MacroDefinition &MD,
+                              const MacroDirective *Undef) {
   }
   
   /// \brief Hook called whenever the 'defined' operator is seen.
@@ -439,15 +443,17 @@ public:
     Second->MacroExpands(MacroNameTok, MD, Range, Args);
   }
 
-  void MacroDefined(const Token &MacroNameTok, const MacroDirective *MD) override {
+  void MacroDefined(const Token &MacroNameTok,
+                    const MacroDirective *MD) override {
     First->MacroDefined(MacroNameTok, MD);
     Second->MacroDefined(MacroNameTok, MD);
   }
 
   void MacroUndefined(const Token &MacroNameTok,
-                      const MacroDefinition &MD) override {
-    First->MacroUndefined(MacroNameTok, MD);
-    Second->MacroUndefined(MacroNameTok, MD);
+                      const MacroDefinition &MD,
+                      const MacroDirective *Undef) override {
+    First->MacroUndefined(MacroNameTok, MD, Undef);
+    Second->MacroUndefined(MacroNameTok, MD, Undef);
   }
 
   void Defined(const Token &MacroNameTok, const MacroDefinition &MD,
diff --git a/include/clang/Lex/PreprocessingRecord.h b/include/clang/Lex/PreprocessingRecord.h
index 826ba33fbb72..fc2c50700400 100644
--- a/include/clang/Lex/PreprocessingRecord.h
+++ b/include/clang/Lex/PreprocessingRecord.h
@@ -488,7 +488,8 @@ namespace clang {
     void MacroExpands(const Token &Id, const MacroDefinition &MD,
                       SourceRange Range, const MacroArgs *Args) override;
     void MacroDefined(const Token &Id, const MacroDirective *MD) override;
-    void MacroUndefined(const Token &Id, const MacroDefinition &MD) override;
+    void MacroUndefined(const Token &Id, const MacroDefinition &MD,
+                        const MacroDirective *Undef) override;
     void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
                             StringRef FileName, bool IsAngled,
                             CharSourceRange FilenameRange,
diff --git a/include/clang/Lex/Preprocessor.h b/include/clang/Lex/Preprocessor.h
index 3efe914daaee..b1a7325c3426 100644
--- a/include/clang/Lex/Preprocessor.h
+++ b/include/clang/Lex/Preprocessor.h
@@ -1263,6 +1263,10 @@ public:
       CachedTokens[CachedLexPos-1] = Tok;
   }
 
+  /// Enter an annotation token into the token stream.
+  void EnterAnnotationToken(SourceRange Range, tok::TokenKind Kind,
+                            void *AnnotationVal);
+
   /// Update the current token to represent the provided
   /// identifier, in order to cache an action performed by typo correction.
   void TypoCorrectToken(const Token &Tok) {
@@ -1602,6 +1606,7 @@ private:
                  *Ident_AbnormalTermination;
 
   const char *getCurLexerEndPos();
+  void diagnoseMissingHeaderInUmbrellaDir(const Module &Mod);
 
 public:
   void PoisonSEHIdentifiers(bool Poison = true); // Borland
@@ -1686,7 +1691,7 @@ public:
                               SmallVectorImpl<char> *SearchPath,
                               SmallVectorImpl<char> *RelativePath,
                               ModuleMap::KnownHeader *SuggestedModule,
-                              bool SkipCache = false);
+                              bool *IsMapped, bool SkipCache = false);
 
   /// \brief Get the DirectoryLookup structure used to find the current
   /// FileEntry, if CurLexer is non-null and if applicable. 
@@ -1962,6 +1967,7 @@ public:
   void HandlePragmaPoison();
   void HandlePragmaSystemHeader(Token &SysHeaderTok);
   void HandlePragmaDependency(Token &DependencyTok);
+  void HandlePragmaModuleImport(Token &Tok);
   void HandlePragmaPushMacro(Token &Tok);
   void HandlePragmaPopMacro(Token &Tok);
   void HandlePragmaIncludeAlias(Token &Tok);
diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 0f16cb975b2a..e24d6436f331 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -1068,6 +1068,12 @@ public:
   /// same special member, we should act as if it is not yet declared.
   llvm::SmallSet<SpecialMemberDecl, 4> SpecialMembersBeingDeclared;
 
+  /// The function definitions which were renamed as part of typo-correction
+  /// to match their respective declarations. We want to keep track of them
+  /// to ensure that we don't emit a "redefinition" error if we encounter a
+  /// correctly named definition after the renamed definition.
+  llvm::SmallPtrSet<const NamedDecl *, 4> TypoCorrectedFunctionDefinitions;
+
   void ReadMethodPool(Selector Sel);
   void updateOutOfDateSelector(Selector Sel);
 
@@ -3117,6 +3123,8 @@ public:
                     const PartialDiagnostic &PrevNote,
                     bool ErrorRecovery = true);
 
+  void MarkTypoCorrectedFunctionDefinition(const NamedDecl *F);
+
   void FindAssociatedClassesAndNamespaces(SourceLocation InstantiationLoc,
                                           ArrayRef<Expr *> Args,
                                    AssociatedNamespaceSet &AssociatedNamespaces,
@@ -3162,6 +3170,7 @@ public:
   bool CheckCallingConvAttr(const AttributeList &attr, CallingConv &CC,
                             const FunctionDecl *FD = nullptr);
   bool CheckNoReturnAttr(const AttributeList &attr);
+  bool CheckNoCallerSavedRegsAttr(const AttributeList &attr);
   bool checkStringLiteralArgumentAttr(const AttributeList &Attr,
                                       unsigned ArgNum, StringRef &Str,
                                       SourceLocation *ArgLocation = nullptr);
@@ -10151,7 +10160,6 @@ private:
   void CheckFloatComparison(SourceLocation Loc, Expr* LHS, Expr* RHS);
   void CheckImplicitConversions(Expr *E, SourceLocation CC = SourceLocation());
   void CheckBoolLikeConversion(Expr *E, SourceLocation CC);
-  void CheckForIntOverflow(Expr *E);
   void CheckUnsequencedOperations(Expr *E);
 
   /// \brief Perform semantic checks on a completed expression. This will either
diff --git a/lib/ARCMigrate/ObjCMT.cpp b/lib/ARCMigrate/ObjCMT.cpp
index 241a7246b621..fcc67da1f774 100644
--- a/lib/ARCMigrate/ObjCMT.cpp
+++ b/lib/ARCMigrate/ObjCMT.cpp
@@ -2189,7 +2189,7 @@ static std::string applyEditsToTemp(const FileEntry *FE,
 
   Rewriter rewriter(SM, LangOpts);
   RewritesReceiver Rec(rewriter);
-  Editor.applyRewrites(Rec);
+  Editor.applyRewrites(Rec, /*adjustRemovals=*/false);
 
   const RewriteBuffer *Buf = rewriter.getRewriteBufferFor(FID);
   SmallString<512> NewText;
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 4626052a8acb..3b526a23edd9 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -7918,6 +7918,8 @@ QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
 
   if (lbaseInfo.getProducesResult() != rbaseInfo.getProducesResult())
     return QualType();
+  if (lbaseInfo.getNoCallerSavedRegs() != rbaseInfo.getNoCallerSavedRegs())
+    return QualType();
 
   // FIXME: some uses, e.g. conditional exprs, really want this to be 'both'.
   bool NoReturn = lbaseInfo.getNoReturn() || rbaseInfo.getNoReturn();
diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
index 95492825eb9d..4fb6051d6f58 100644
--- a/lib/AST/ASTImporter.cpp
+++ b/lib/AST/ASTImporter.cpp
@@ -14,6 +14,7 @@
 #include "clang/AST/ASTImporter.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTDiagnostic.h"
+#include "clang/AST/ASTStructuralEquivalence.h"
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclVisitor.h"
@@ -321,1396 +322,12 @@ namespace clang {
   };
 }
 
-using namespace clang;
-
-//----------------------------------------------------------------------------
-// Structural Equivalence
-//----------------------------------------------------------------------------
-
-namespace {
-  struct StructuralEquivalenceContext {
-    /// \brief AST contexts for which we are checking structural equivalence.
-    ASTContext &C1, &C2;
-    
-    /// \brief The set of "tentative" equivalences between two canonical 
-    /// declarations, mapping from a declaration in the first context to the
-    /// declaration in the second context that we believe to be equivalent.
-    llvm::DenseMap<Decl *, Decl *> TentativeEquivalences;
-    
-    /// \brief Queue of declarations in the first context whose equivalence
-    /// with a declaration in the second context still needs to be verified.
-    std::deque<Decl *> DeclsToCheck;
-    
-    /// \brief Declaration (from, to) pairs that are known not to be equivalent
-    /// (which we have already complained about).
-    llvm::DenseSet<std::pair<Decl *, Decl *> > &NonEquivalentDecls;
-    
-    /// \brief Whether we're being strict about the spelling of types when 
-    /// unifying two types.
-    bool StrictTypeSpelling;
-
-    /// \brief Whether to complain about failures.
-    bool Complain;
-
-    /// \brief \c true if the last diagnostic came from C2.
-    bool LastDiagFromC2;
-
-    StructuralEquivalenceContext(ASTContext &C1, ASTContext &C2,
-               llvm::DenseSet<std::pair<Decl *, Decl *> > &NonEquivalentDecls,
-                                 bool StrictTypeSpelling = false,
-                                 bool Complain = true)
-      : C1(C1), C2(C2), NonEquivalentDecls(NonEquivalentDecls),
-        StrictTypeSpelling(StrictTypeSpelling), Complain(Complain),
-        LastDiagFromC2(false) {}
-
-    /// \brief Determine whether the two declarations are structurally
-    /// equivalent.
-    bool IsStructurallyEquivalent(Decl *D1, Decl *D2);
-    
-    /// \brief Determine whether the two types are structurally equivalent.
-    bool IsStructurallyEquivalent(QualType T1, QualType T2);
-
-  private:
-    /// \brief Finish checking all of the structural equivalences.
-    ///
-    /// \returns true if an error occurred, false otherwise.
-    bool Finish();
-    
-  public:
-    DiagnosticBuilder Diag1(SourceLocation Loc, unsigned DiagID) {
-      assert(Complain && "Not allowed to complain");
-      if (LastDiagFromC2)
-        C1.getDiagnostics().notePriorDiagnosticFrom(C2.getDiagnostics());
-      LastDiagFromC2 = false;
-      return C1.getDiagnostics().Report(Loc, DiagID);
-    }
-
-    DiagnosticBuilder Diag2(SourceLocation Loc, unsigned DiagID) {
-      assert(Complain && "Not allowed to complain");
-      if (!LastDiagFromC2)
-        C2.getDiagnostics().notePriorDiagnosticFrom(C1.getDiagnostics());
-      LastDiagFromC2 = true;
-      return C2.getDiagnostics().Report(Loc, DiagID);
-    }
-  };
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     QualType T1, QualType T2);
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     Decl *D1, Decl *D2);
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     const TemplateArgument &Arg1,
-                                     const TemplateArgument &Arg2);
-
-/// \brief Determine structural equivalence of two expressions.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     Expr *E1, Expr *E2) {
-  if (!E1 || !E2)
-    return E1 == E2;
-  
-  // FIXME: Actually perform a structural comparison!
-  return true;
-}
-
-/// \brief Determine whether two identifiers are equivalent.
-static bool IsStructurallyEquivalent(const IdentifierInfo *Name1,
-                                     const IdentifierInfo *Name2) {
-  if (!Name1 || !Name2)
-    return Name1 == Name2;
-  
-  return Name1->getName() == Name2->getName();
-}
-
-/// \brief Determine whether two nested-name-specifiers are equivalent.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     NestedNameSpecifier *NNS1,
-                                     NestedNameSpecifier *NNS2) {
-  if (NNS1->getKind() != NNS2->getKind())
-    return false;
-
-  NestedNameSpecifier *Prefix1 = NNS1->getPrefix(),
-      *Prefix2 = NNS2->getPrefix();
-  if ((bool)Prefix1 != (bool)Prefix2)
-    return false;
-
-  if (Prefix1)
-    if (!IsStructurallyEquivalent(Context, Prefix1, Prefix2))
-      return false;
-
-  switch (NNS1->getKind()) {
-  case NestedNameSpecifier::Identifier:
-    return IsStructurallyEquivalent(NNS1->getAsIdentifier(),
-                                    NNS2->getAsIdentifier());
-  case NestedNameSpecifier::Namespace:
-    return IsStructurallyEquivalent(Context, NNS1->getAsNamespace(),
-                                    NNS2->getAsNamespace());
-  case NestedNameSpecifier::NamespaceAlias:
-    return IsStructurallyEquivalent(Context, NNS1->getAsNamespaceAlias(),
-                                    NNS2->getAsNamespaceAlias());
-  case NestedNameSpecifier::TypeSpec:
-  case NestedNameSpecifier::TypeSpecWithTemplate:
-    return IsStructurallyEquivalent(Context, QualType(NNS1->getAsType(), 0),
-                                    QualType(NNS2->getAsType(), 0));
-  case NestedNameSpecifier::Global:
-    return true;
-  case NestedNameSpecifier::Super:
-    return IsStructurallyEquivalent(Context, NNS1->getAsRecordDecl(),
-                                    NNS2->getAsRecordDecl());
-  }
-  return false;
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     const TemplateName &N1,
-                                     const TemplateName &N2) {
-  if (N1.getKind() != N2.getKind())
-    return false;
-  switch (N1.getKind()) {
-  case TemplateName::Template:
-    return IsStructurallyEquivalent(Context, N1.getAsTemplateDecl(),
-                                    N2.getAsTemplateDecl());
-
-  case TemplateName::OverloadedTemplate: {
-    OverloadedTemplateStorage *OS1 = N1.getAsOverloadedTemplate(),
-        *OS2 = N2.getAsOverloadedTemplate();
-    OverloadedTemplateStorage::iterator I1 = OS1->begin(), I2 = OS2->begin(),
-        E1 = OS1->end(), E2 = OS2->end();
-    for (; I1 != E1 && I2 != E2; ++I1, ++I2)
-      if (!IsStructurallyEquivalent(Context, *I1, *I2))
-        return false;
-    return I1 == E1 && I2 == E2;
-  }
-
-  case TemplateName::QualifiedTemplate: {
-    QualifiedTemplateName *QN1 = N1.getAsQualifiedTemplateName(),
-        *QN2 = N2.getAsQualifiedTemplateName();
-    return IsStructurallyEquivalent(Context, QN1->getDecl(), QN2->getDecl()) &&
-        IsStructurallyEquivalent(Context, QN1->getQualifier(),
-                                 QN2->getQualifier());
-  }
-
-  case TemplateName::DependentTemplate: {
-      DependentTemplateName *DN1 = N1.getAsDependentTemplateName(),
-          *DN2 = N2.getAsDependentTemplateName();
-      if (!IsStructurallyEquivalent(Context, DN1->getQualifier(),
-                                    DN2->getQualifier()))
-        return false;
-      if (DN1->isIdentifier() && DN2->isIdentifier())
-        return IsStructurallyEquivalent(DN1->getIdentifier(),
-                                        DN2->getIdentifier());
-      else if (DN1->isOverloadedOperator() && DN2->isOverloadedOperator())
-        return DN1->getOperator() == DN2->getOperator();
-      return false;
-  }
-
-  case TemplateName::SubstTemplateTemplateParm: {
-    SubstTemplateTemplateParmStorage *TS1 = N1.getAsSubstTemplateTemplateParm(),
-        *TS2 = N2.getAsSubstTemplateTemplateParm();
-    return IsStructurallyEquivalent(Context, TS1->getParameter(),
-                                    TS2->getParameter()) &&
-        IsStructurallyEquivalent(Context, TS1->getReplacement(),
-                                 TS2->getReplacement());
-    }
-  case TemplateName::SubstTemplateTemplateParmPack: {
-    SubstTemplateTemplateParmPackStorage
-        *P1 = N1.getAsSubstTemplateTemplateParmPack(),
-        *P2 = N2.getAsSubstTemplateTemplateParmPack();
-    return IsStructurallyEquivalent(Context, P1->getArgumentPack(),
-                                    P2->getArgumentPack()) &&
-        IsStructurallyEquivalent(Context, P1->getParameterPack(),
-                                 P2->getParameterPack());
-  }
-  }
-  return false;
-}
-
-/// \brief Determine whether two template arguments are equivalent.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     const TemplateArgument &Arg1,
-                                     const TemplateArgument &Arg2) {
-  if (Arg1.getKind() != Arg2.getKind())
-    return false;
-
-  switch (Arg1.getKind()) {
-  case TemplateArgument::Null:
-    return true;
-      
-  case TemplateArgument::Type:
-    return Context.IsStructurallyEquivalent(Arg1.getAsType(), Arg2.getAsType());
-
-  case TemplateArgument::Integral:
-    if (!Context.IsStructurallyEquivalent(Arg1.getIntegralType(), 
-                                          Arg2.getIntegralType()))
-      return false;
-    
-    return llvm::APSInt::isSameValue(Arg1.getAsIntegral(), Arg2.getAsIntegral());
-      
-  case TemplateArgument::Declaration:
-    return Context.IsStructurallyEquivalent(Arg1.getAsDecl(), Arg2.getAsDecl());
-
-  case TemplateArgument::NullPtr:
-    return true; // FIXME: Is this correct?
-
-  case TemplateArgument::Template:
-    return IsStructurallyEquivalent(Context, 
-                                    Arg1.getAsTemplate(), 
-                                    Arg2.getAsTemplate());
-
-  case TemplateArgument::TemplateExpansion:
-    return IsStructurallyEquivalent(Context, 
-                                    Arg1.getAsTemplateOrTemplatePattern(), 
-                                    Arg2.getAsTemplateOrTemplatePattern());
-
-  case TemplateArgument::Expression:
-    return IsStructurallyEquivalent(Context, 
-                                    Arg1.getAsExpr(), Arg2.getAsExpr());
-      
-  case TemplateArgument::Pack:
-    if (Arg1.pack_size() != Arg2.pack_size())
-      return false;
-      
-    for (unsigned I = 0, N = Arg1.pack_size(); I != N; ++I)
-      if (!IsStructurallyEquivalent(Context, 
-                                    Arg1.pack_begin()[I],
-                                    Arg2.pack_begin()[I]))
-        return false;
-      
-    return true;
-  }
-  
-  llvm_unreachable("Invalid template argument kind");
-}
-
-/// \brief Determine structural equivalence for the common part of array 
-/// types.
-static bool IsArrayStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                          const ArrayType *Array1, 
-                                          const ArrayType *Array2) {
-  if (!IsStructurallyEquivalent(Context, 
-                                Array1->getElementType(), 
-                                Array2->getElementType()))
-    return false;
-  if (Array1->getSizeModifier() != Array2->getSizeModifier())
-    return false;
-  if (Array1->getIndexTypeQualifiers() != Array2->getIndexTypeQualifiers())
-    return false;
-  
-  return true;
-}
-
-/// \brief Determine structural equivalence of two types.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     QualType T1, QualType T2) {
-  if (T1.isNull() || T2.isNull())
-    return T1.isNull() && T2.isNull();
-  
-  if (!Context.StrictTypeSpelling) {
-    // We aren't being strict about token-to-token equivalence of types,
-    // so map down to the canonical type.
-    T1 = Context.C1.getCanonicalType(T1);
-    T2 = Context.C2.getCanonicalType(T2);
-  }
-  
-  if (T1.getQualifiers() != T2.getQualifiers())
-    return false;
-  
-  Type::TypeClass TC = T1->getTypeClass();
-  
-  if (T1->getTypeClass() != T2->getTypeClass()) {
-    // Compare function types with prototypes vs. without prototypes as if
-    // both did not have prototypes.
-    if (T1->getTypeClass() == Type::FunctionProto &&
-        T2->getTypeClass() == Type::FunctionNoProto)
-      TC = Type::FunctionNoProto;
-    else if (T1->getTypeClass() == Type::FunctionNoProto &&
-             T2->getTypeClass() == Type::FunctionProto)
-      TC = Type::FunctionNoProto;
-    else
-      return false;
-  }
-  
-  switch (TC) {
-  case Type::Builtin:
-    // FIXME: Deal with Char_S/Char_U. 
-    if (cast<BuiltinType>(T1)->getKind() != cast<BuiltinType>(T2)->getKind())
-      return false;
-    break;
-  
-  case Type::Complex:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<ComplexType>(T1)->getElementType(),
-                                  cast<ComplexType>(T2)->getElementType()))
-      return false;
-    break;
-  
-  case Type::Adjusted:
-  case Type::Decayed:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<AdjustedType>(T1)->getOriginalType(),
-                                  cast<AdjustedType>(T2)->getOriginalType()))
-      return false;
-    break;
-
-  case Type::Pointer:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<PointerType>(T1)->getPointeeType(),
-                                  cast<PointerType>(T2)->getPointeeType()))
-      return false;
-    break;
-
-  case Type::BlockPointer:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<BlockPointerType>(T1)->getPointeeType(),
-                                  cast<BlockPointerType>(T2)->getPointeeType()))
-      return false;
-    break;
-
-  case Type::LValueReference:
-  case Type::RValueReference: {
-    const ReferenceType *Ref1 = cast<ReferenceType>(T1);
-    const ReferenceType *Ref2 = cast<ReferenceType>(T2);
-    if (Ref1->isSpelledAsLValue() != Ref2->isSpelledAsLValue())
-      return false;
-    if (Ref1->isInnerRef() != Ref2->isInnerRef())
-      return false;
-    if (!IsStructurallyEquivalent(Context,
-                                  Ref1->getPointeeTypeAsWritten(),
-                                  Ref2->getPointeeTypeAsWritten()))
-      return false;
-    break;
-  }
-      
-  case Type::MemberPointer: {
-    const MemberPointerType *MemPtr1 = cast<MemberPointerType>(T1);
-    const MemberPointerType *MemPtr2 = cast<MemberPointerType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  MemPtr1->getPointeeType(),
-                                  MemPtr2->getPointeeType()))
-      return false;
-    if (!IsStructurallyEquivalent(Context,
-                                  QualType(MemPtr1->getClass(), 0),
-                                  QualType(MemPtr2->getClass(), 0)))
-      return false;
-    break;
-  }
-      
-  case Type::ConstantArray: {
-    const ConstantArrayType *Array1 = cast<ConstantArrayType>(T1);
-    const ConstantArrayType *Array2 = cast<ConstantArrayType>(T2);
-    if (!llvm::APInt::isSameValue(Array1->getSize(), Array2->getSize()))
-      return false;
-    
-    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
-      return false;
-    break;
-  }
-
-  case Type::IncompleteArray:
-    if (!IsArrayStructurallyEquivalent(Context, 
-                                       cast<ArrayType>(T1), 
-                                       cast<ArrayType>(T2)))
-      return false;
-    break;
-      
-  case Type::VariableArray: {
-    const VariableArrayType *Array1 = cast<VariableArrayType>(T1);
-    const VariableArrayType *Array2 = cast<VariableArrayType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Array1->getSizeExpr(), Array2->getSizeExpr()))
-      return false;
-    
-    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
-      return false;
-    
-    break;
-  }
-  
-  case Type::DependentSizedArray: {
-    const DependentSizedArrayType *Array1 = cast<DependentSizedArrayType>(T1);
-    const DependentSizedArrayType *Array2 = cast<DependentSizedArrayType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Array1->getSizeExpr(), Array2->getSizeExpr()))
-      return false;
-    
-    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
-      return false;
-    
-    break;
-  }
-      
-  case Type::DependentSizedExtVector: {
-    const DependentSizedExtVectorType *Vec1
-      = cast<DependentSizedExtVectorType>(T1);
-    const DependentSizedExtVectorType *Vec2
-      = cast<DependentSizedExtVectorType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Vec1->getSizeExpr(), Vec2->getSizeExpr()))
-      return false;
-    if (!IsStructurallyEquivalent(Context, 
-                                  Vec1->getElementType(), 
-                                  Vec2->getElementType()))
-      return false;
-    break;
-  }
-   
-  case Type::Vector: 
-  case Type::ExtVector: {
-    const VectorType *Vec1 = cast<VectorType>(T1);
-    const VectorType *Vec2 = cast<VectorType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Vec1->getElementType(),
-                                  Vec2->getElementType()))
-      return false;
-    if (Vec1->getNumElements() != Vec2->getNumElements())
-      return false;
-    if (Vec1->getVectorKind() != Vec2->getVectorKind())
-      return false;
-    break;
-  }
-
-  case Type::FunctionProto: {
-    const FunctionProtoType *Proto1 = cast<FunctionProtoType>(T1);
-    const FunctionProtoType *Proto2 = cast<FunctionProtoType>(T2);
-    if (Proto1->getNumParams() != Proto2->getNumParams())
-      return false;
-    for (unsigned I = 0, N = Proto1->getNumParams(); I != N; ++I) {
-      if (!IsStructurallyEquivalent(Context, Proto1->getParamType(I),
-                                    Proto2->getParamType(I)))
-        return false;
-    }
-    if (Proto1->isVariadic() != Proto2->isVariadic())
-      return false;
-    if (Proto1->getExceptionSpecType() != Proto2->getExceptionSpecType())
-      return false;
-    if (Proto1->getExceptionSpecType() == EST_Dynamic) {
-      if (Proto1->getNumExceptions() != Proto2->getNumExceptions())
-        return false;
-      for (unsigned I = 0, N = Proto1->getNumExceptions(); I != N; ++I) {
-        if (!IsStructurallyEquivalent(Context,
-                                      Proto1->getExceptionType(I),
-                                      Proto2->getExceptionType(I)))
-          return false;
-      }
-    } else if (Proto1->getExceptionSpecType() == EST_ComputedNoexcept) {
-      if (!IsStructurallyEquivalent(Context,
-                                    Proto1->getNoexceptExpr(),
-                                    Proto2->getNoexceptExpr()))
-        return false;
-    }
-    if (Proto1->getTypeQuals() != Proto2->getTypeQuals())
-      return false;
-    
-    // Fall through to check the bits common with FunctionNoProtoType.
-  }
-      
-  case Type::FunctionNoProto: {
-    const FunctionType *Function1 = cast<FunctionType>(T1);
-    const FunctionType *Function2 = cast<FunctionType>(T2);
-    if (!IsStructurallyEquivalent(Context, Function1->getReturnType(),
-                                  Function2->getReturnType()))
-      return false;
-    if (Function1->getExtInfo() != Function2->getExtInfo())
-      return false;
-    break;
-  }
-   
-  case Type::UnresolvedUsing:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<UnresolvedUsingType>(T1)->getDecl(),
-                                  cast<UnresolvedUsingType>(T2)->getDecl()))
-      return false;
-      
-    break;
-
-  case Type::Attributed:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<AttributedType>(T1)->getModifiedType(),
-                                  cast<AttributedType>(T2)->getModifiedType()))
-      return false;
-    if (!IsStructurallyEquivalent(Context,
-                                cast<AttributedType>(T1)->getEquivalentType(),
-                                cast<AttributedType>(T2)->getEquivalentType()))
-      return false;
-    break;
-      
-  case Type::Paren:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<ParenType>(T1)->getInnerType(),
-                                  cast<ParenType>(T2)->getInnerType()))
-      return false;
-    break;
-
-  case Type::Typedef:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<TypedefType>(T1)->getDecl(),
-                                  cast<TypedefType>(T2)->getDecl()))
-      return false;
-    break;
-      
-  case Type::TypeOfExpr:
-    if (!IsStructurallyEquivalent(Context,
-                                cast<TypeOfExprType>(T1)->getUnderlyingExpr(),
-                                cast<TypeOfExprType>(T2)->getUnderlyingExpr()))
-      return false;
-    break;
-      
-  case Type::TypeOf:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<TypeOfType>(T1)->getUnderlyingType(),
-                                  cast<TypeOfType>(T2)->getUnderlyingType()))
-      return false;
-    break;
-
-  case Type::UnaryTransform:
-    if (!IsStructurallyEquivalent(Context,
-                             cast<UnaryTransformType>(T1)->getUnderlyingType(),
-                             cast<UnaryTransformType>(T1)->getUnderlyingType()))
-      return false;
-    break;
-
-  case Type::Decltype:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<DecltypeType>(T1)->getUnderlyingExpr(),
-                                  cast<DecltypeType>(T2)->getUnderlyingExpr()))
-      return false;
-    break;
-
-  case Type::Auto:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<AutoType>(T1)->getDeducedType(),
-                                  cast<AutoType>(T2)->getDeducedType()))
-      return false;
-    break;
-
-  case Type::DeducedTemplateSpecialization: {
-    auto *DT1 = cast<DeducedTemplateSpecializationType>(T1);
-    auto *DT2 = cast<DeducedTemplateSpecializationType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  DT1->getTemplateName(),
-                                  DT2->getTemplateName()))
-      return false;
-    if (!IsStructurallyEquivalent(Context,
-                                  DT1->getDeducedType(),
-                                  DT2->getDeducedType()))
-      return false;
-    break;
-  }
-
-  case Type::Record:
-  case Type::Enum:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<TagType>(T1)->getDecl(),
-                                  cast<TagType>(T2)->getDecl()))
-      return false;
-    break;
-
-  case Type::TemplateTypeParm: {
-    const TemplateTypeParmType *Parm1 = cast<TemplateTypeParmType>(T1);
-    const TemplateTypeParmType *Parm2 = cast<TemplateTypeParmType>(T2);
-    if (Parm1->getDepth() != Parm2->getDepth())
-      return false;
-    if (Parm1->getIndex() != Parm2->getIndex())
-      return false;
-    if (Parm1->isParameterPack() != Parm2->isParameterPack())
-      return false;
-    
-    // Names of template type parameters are never significant.
-    break;
-  }
-      
-  case Type::SubstTemplateTypeParm: {
-    const SubstTemplateTypeParmType *Subst1
-      = cast<SubstTemplateTypeParmType>(T1);
-    const SubstTemplateTypeParmType *Subst2
-      = cast<SubstTemplateTypeParmType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  QualType(Subst1->getReplacedParameter(), 0),
-                                  QualType(Subst2->getReplacedParameter(), 0)))
-      return false;
-    if (!IsStructurallyEquivalent(Context, 
-                                  Subst1->getReplacementType(),
-                                  Subst2->getReplacementType()))
-      return false;
-    break;
-  }
-
-  case Type::SubstTemplateTypeParmPack: {
-    const SubstTemplateTypeParmPackType *Subst1
-      = cast<SubstTemplateTypeParmPackType>(T1);
-    const SubstTemplateTypeParmPackType *Subst2
-      = cast<SubstTemplateTypeParmPackType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  QualType(Subst1->getReplacedParameter(), 0),
-                                  QualType(Subst2->getReplacedParameter(), 0)))
-      return false;
-    if (!IsStructurallyEquivalent(Context, 
-                                  Subst1->getArgumentPack(),
-                                  Subst2->getArgumentPack()))
-      return false;
-    break;
-  }
-  case Type::TemplateSpecialization: {
-    const TemplateSpecializationType *Spec1
-      = cast<TemplateSpecializationType>(T1);
-    const TemplateSpecializationType *Spec2
-      = cast<TemplateSpecializationType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  Spec1->getTemplateName(),
-                                  Spec2->getTemplateName()))
-      return false;
-    if (Spec1->getNumArgs() != Spec2->getNumArgs())
-      return false;
-    for (unsigned I = 0, N = Spec1->getNumArgs(); I != N; ++I) {
-      if (!IsStructurallyEquivalent(Context, 
-                                    Spec1->getArg(I), Spec2->getArg(I)))
-        return false;
-    }
-    break;
-  }
-      
-  case Type::Elaborated: {
-    const ElaboratedType *Elab1 = cast<ElaboratedType>(T1);
-    const ElaboratedType *Elab2 = cast<ElaboratedType>(T2);
-    // CHECKME: what if a keyword is ETK_None or ETK_typename ?
-    if (Elab1->getKeyword() != Elab2->getKeyword())
-      return false;
-    if (!IsStructurallyEquivalent(Context, 
-                                  Elab1->getQualifier(), 
-                                  Elab2->getQualifier()))
-      return false;
-    if (!IsStructurallyEquivalent(Context,
-                                  Elab1->getNamedType(),
-                                  Elab2->getNamedType()))
-      return false;
-    break;
-  }
-
-  case Type::InjectedClassName: {
-    const InjectedClassNameType *Inj1 = cast<InjectedClassNameType>(T1);
-    const InjectedClassNameType *Inj2 = cast<InjectedClassNameType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  Inj1->getInjectedSpecializationType(),
-                                  Inj2->getInjectedSpecializationType()))
-      return false;
-    break;
-  }
-
-  case Type::DependentName: {
-    const DependentNameType *Typename1 = cast<DependentNameType>(T1);
-    const DependentNameType *Typename2 = cast<DependentNameType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Typename1->getQualifier(),
-                                  Typename2->getQualifier()))
-      return false;
-    if (!IsStructurallyEquivalent(Typename1->getIdentifier(),
-                                  Typename2->getIdentifier()))
-      return false;
-    
-    break;
-  }
-  
-  case Type::DependentTemplateSpecialization: {
-    const DependentTemplateSpecializationType *Spec1 =
-      cast<DependentTemplateSpecializationType>(T1);
-    const DependentTemplateSpecializationType *Spec2 =
-      cast<DependentTemplateSpecializationType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Spec1->getQualifier(),
-                                  Spec2->getQualifier()))
-      return false;
-    if (!IsStructurallyEquivalent(Spec1->getIdentifier(),
-                                  Spec2->getIdentifier()))
-      return false;
-    if (Spec1->getNumArgs() != Spec2->getNumArgs())
-      return false;
-    for (unsigned I = 0, N = Spec1->getNumArgs(); I != N; ++I) {
-      if (!IsStructurallyEquivalent(Context,
-                                    Spec1->getArg(I), Spec2->getArg(I)))
-        return false;
-    }
-    break;
-  }
-
-  case Type::PackExpansion:
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<PackExpansionType>(T1)->getPattern(),
-                                  cast<PackExpansionType>(T2)->getPattern()))
-      return false;
-    break;
-
-  case Type::ObjCInterface: {
-    const ObjCInterfaceType *Iface1 = cast<ObjCInterfaceType>(T1);
-    const ObjCInterfaceType *Iface2 = cast<ObjCInterfaceType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Iface1->getDecl(), Iface2->getDecl()))
-      return false;
-    break;
-  }
-
-  case Type::ObjCTypeParam: {
-    const ObjCTypeParamType *Obj1 = cast<ObjCTypeParamType>(T1);
-    const ObjCTypeParamType *Obj2 = cast<ObjCTypeParamType>(T2);
-    if (!IsStructurallyEquivalent(Context, Obj1->getDecl(),
-                                  Obj2->getDecl()))
-      return false;
-
-    if (Obj1->getNumProtocols() != Obj2->getNumProtocols())
-      return false;
-    for (unsigned I = 0, N = Obj1->getNumProtocols(); I != N; ++I) {
-      if (!IsStructurallyEquivalent(Context,
-                                    Obj1->getProtocol(I),
-                                    Obj2->getProtocol(I)))
-        return false;
-    }
-    break;
-  }
-  case Type::ObjCObject: {
-    const ObjCObjectType *Obj1 = cast<ObjCObjectType>(T1);
-    const ObjCObjectType *Obj2 = cast<ObjCObjectType>(T2);
-    if (!IsStructurallyEquivalent(Context,
-                                  Obj1->getBaseType(),
-                                  Obj2->getBaseType()))
-      return false;
-    if (Obj1->getNumProtocols() != Obj2->getNumProtocols())
-      return false;
-    for (unsigned I = 0, N = Obj1->getNumProtocols(); I != N; ++I) {
-      if (!IsStructurallyEquivalent(Context,
-                                    Obj1->getProtocol(I),
-                                    Obj2->getProtocol(I)))
-        return false;
-    }
-    break;
-  }
-
-  case Type::ObjCObjectPointer: {
-    const ObjCObjectPointerType *Ptr1 = cast<ObjCObjectPointerType>(T1);
-    const ObjCObjectPointerType *Ptr2 = cast<ObjCObjectPointerType>(T2);
-    if (!IsStructurallyEquivalent(Context, 
-                                  Ptr1->getPointeeType(),
-                                  Ptr2->getPointeeType()))
-      return false;
-    break;
-  }
-
-  case Type::Atomic: {
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<AtomicType>(T1)->getValueType(),
-                                  cast<AtomicType>(T2)->getValueType()))
-      return false;
-    break;
-  }
-
-  case Type::Pipe: {
-    if (!IsStructurallyEquivalent(Context,
-                                  cast<PipeType>(T1)->getElementType(),
-                                  cast<PipeType>(T2)->getElementType()))
-      return false;
-    break;
-  }
-
-  } // end switch
-
-  return true;
-}
-
-/// \brief Determine structural equivalence of two fields.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     FieldDecl *Field1, FieldDecl *Field2) {
-  RecordDecl *Owner2 = cast<RecordDecl>(Field2->getDeclContext());
-
-  // For anonymous structs/unions, match up the anonymous struct/union type
-  // declarations directly, so that we don't go off searching for anonymous
-  // types
-  if (Field1->isAnonymousStructOrUnion() &&
-      Field2->isAnonymousStructOrUnion()) {
-    RecordDecl *D1 = Field1->getType()->castAs<RecordType>()->getDecl();
-    RecordDecl *D2 = Field2->getType()->castAs<RecordType>()->getDecl();
-    return IsStructurallyEquivalent(Context, D1, D2);
-  }
-    
-  // Check for equivalent field names.
-  IdentifierInfo *Name1 = Field1->getIdentifier();
-  IdentifierInfo *Name2 = Field2->getIdentifier();
-  if (!::IsStructurallyEquivalent(Name1, Name2))
-    return false;
-
-  if (!IsStructurallyEquivalent(Context,
-                                Field1->getType(), Field2->getType())) {
-    if (Context.Complain) {
-      Context.Diag2(Owner2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-        << Context.C2.getTypeDeclType(Owner2);
-      Context.Diag2(Field2->getLocation(), diag::note_odr_field)
-        << Field2->getDeclName() << Field2->getType();
-      Context.Diag1(Field1->getLocation(), diag::note_odr_field)
-        << Field1->getDeclName() << Field1->getType();
-    }
-    return false;
-  }
-  
-  if (Field1->isBitField() != Field2->isBitField()) {
-    if (Context.Complain) {
-      Context.Diag2(Owner2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-        << Context.C2.getTypeDeclType(Owner2);
-      if (Field1->isBitField()) {
-        Context.Diag1(Field1->getLocation(), diag::note_odr_bit_field)
-        << Field1->getDeclName() << Field1->getType()
-        << Field1->getBitWidthValue(Context.C1);
-        Context.Diag2(Field2->getLocation(), diag::note_odr_not_bit_field)
-        << Field2->getDeclName();
-      } else {
-        Context.Diag2(Field2->getLocation(), diag::note_odr_bit_field)
-        << Field2->getDeclName() << Field2->getType()
-        << Field2->getBitWidthValue(Context.C2);
-        Context.Diag1(Field1->getLocation(), diag::note_odr_not_bit_field)
-        << Field1->getDeclName();
-      }
-    }
-    return false;
-  }
-  
-  if (Field1->isBitField()) {
-    // Make sure that the bit-fields are the same length.
-    unsigned Bits1 = Field1->getBitWidthValue(Context.C1);
-    unsigned Bits2 = Field2->getBitWidthValue(Context.C2);
-    
-    if (Bits1 != Bits2) {
-      if (Context.Complain) {
-        Context.Diag2(Owner2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-          << Context.C2.getTypeDeclType(Owner2);
-        Context.Diag2(Field2->getLocation(), diag::note_odr_bit_field)
-          << Field2->getDeclName() << Field2->getType() << Bits2;
-        Context.Diag1(Field1->getLocation(), diag::note_odr_bit_field)
-          << Field1->getDeclName() << Field1->getType() << Bits1;
-      }
-      return false;
-    }
-  }
-
-  return true;
-}
-
-/// \brief Find the index of the given anonymous struct/union within its
-/// context.
-///
-/// \returns Returns the index of this anonymous struct/union in its context,
-/// including the next assigned index (if none of them match). Returns an
-/// empty option if the context is not a record, i.e.. if the anonymous
-/// struct/union is at namespace or block scope.
-static Optional<unsigned> findUntaggedStructOrUnionIndex(RecordDecl *Anon) {
-  ASTContext &Context = Anon->getASTContext();
-  QualType AnonTy = Context.getRecordType(Anon);
-
-  RecordDecl *Owner = dyn_cast<RecordDecl>(Anon->getDeclContext());
-  if (!Owner)
-    return None;
-
-  unsigned Index = 0;
-  for (const auto *D : Owner->noload_decls()) {
-    const auto *F = dyn_cast<FieldDecl>(D);
-    if (!F)
-      continue;
-
-    if (F->isAnonymousStructOrUnion()) {
-      if (Context.hasSameType(F->getType(), AnonTy))
-        break;
-      ++Index;
-      continue;
-    }
-
-    // If the field looks like this:
-    // struct { ... } A;
-    QualType FieldType = F->getType();
-    if (const auto *RecType = dyn_cast<RecordType>(FieldType)) {
-      const RecordDecl *RecDecl = RecType->getDecl();
-      if (RecDecl->getDeclContext() == Owner &&
-          !RecDecl->getIdentifier()) {
-        if (Context.hasSameType(FieldType, AnonTy))
-          break;
-        ++Index;
-        continue;
-      }
-    }
-  }
-
-  return Index;
-}
-
-/// \brief Determine structural equivalence of two records.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     RecordDecl *D1, RecordDecl *D2) {
-  if (D1->isUnion() != D2->isUnion()) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-        << Context.C2.getTypeDeclType(D2);
-      Context.Diag1(D1->getLocation(), diag::note_odr_tag_kind_here)
-        << D1->getDeclName() << (unsigned)D1->getTagKind();
-    }
-    return false;
-  }
-
-  if (D1->isAnonymousStructOrUnion() && D2->isAnonymousStructOrUnion()) {
-    // If both anonymous structs/unions are in a record context, make sure
-    // they occur in the same location in the context records.
-    if (Optional<unsigned> Index1 = findUntaggedStructOrUnionIndex(D1)) {
-      if (Optional<unsigned> Index2 = findUntaggedStructOrUnionIndex(D2)) {
-        if (*Index1 != *Index2)
-          return false;
-      }
-    }
-  }
-
-  // If both declarations are class template specializations, we know
-  // the ODR applies, so check the template and template arguments.
-  ClassTemplateSpecializationDecl *Spec1
-    = dyn_cast<ClassTemplateSpecializationDecl>(D1);
-  ClassTemplateSpecializationDecl *Spec2
-    = dyn_cast<ClassTemplateSpecializationDecl>(D2);
-  if (Spec1 && Spec2) {
-    // Check that the specialized templates are the same.
-    if (!IsStructurallyEquivalent(Context, Spec1->getSpecializedTemplate(),
-                                  Spec2->getSpecializedTemplate()))
-      return false;
-    
-    // Check that the template arguments are the same.
-    if (Spec1->getTemplateArgs().size() != Spec2->getTemplateArgs().size())
-      return false;
-    
-    for (unsigned I = 0, N = Spec1->getTemplateArgs().size(); I != N; ++I)
-      if (!IsStructurallyEquivalent(Context, 
-                                    Spec1->getTemplateArgs().get(I),
-                                    Spec2->getTemplateArgs().get(I)))
-        return false;
-  }  
-  // If one is a class template specialization and the other is not, these
-  // structures are different.
-  else if (Spec1 || Spec2)
-    return false;
-
-  // Compare the definitions of these two records. If either or both are
-  // incomplete, we assume that they are equivalent.
-  D1 = D1->getDefinition();
-  D2 = D2->getDefinition();
-  if (!D1 || !D2)
-    return true;
-  
-  if (CXXRecordDecl *D1CXX = dyn_cast<CXXRecordDecl>(D1)) {
-    if (CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(D2)) {
-      if (D1CXX->getNumBases() != D2CXX->getNumBases()) {
-        if (Context.Complain) {
-          Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-            << Context.C2.getTypeDeclType(D2);
-          Context.Diag2(D2->getLocation(), diag::note_odr_number_of_bases)
-            << D2CXX->getNumBases();
-          Context.Diag1(D1->getLocation(), diag::note_odr_number_of_bases)
-            << D1CXX->getNumBases();
-        }
-        return false;
-      }
-      
-      // Check the base classes. 
-      for (CXXRecordDecl::base_class_iterator Base1 = D1CXX->bases_begin(), 
-                                           BaseEnd1 = D1CXX->bases_end(),
-                                                Base2 = D2CXX->bases_begin();
-           Base1 != BaseEnd1;
-           ++Base1, ++Base2) {        
-        if (!IsStructurallyEquivalent(Context, 
-                                      Base1->getType(), Base2->getType())) {
-          if (Context.Complain) {
-            Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-              << Context.C2.getTypeDeclType(D2);
-            Context.Diag2(Base2->getLocStart(), diag::note_odr_base)
-              << Base2->getType()
-              << Base2->getSourceRange();
-            Context.Diag1(Base1->getLocStart(), diag::note_odr_base)
-              << Base1->getType()
-              << Base1->getSourceRange();
-          }
-          return false;
-        }
-        
-        // Check virtual vs. non-virtual inheritance mismatch.
-        if (Base1->isVirtual() != Base2->isVirtual()) {
-          if (Context.Complain) {
-            Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-              << Context.C2.getTypeDeclType(D2);
-            Context.Diag2(Base2->getLocStart(),
-                          diag::note_odr_virtual_base)
-              << Base2->isVirtual() << Base2->getSourceRange();
-            Context.Diag1(Base1->getLocStart(), diag::note_odr_base)
-              << Base1->isVirtual()
-              << Base1->getSourceRange();
-          }
-          return false;
-        }
-      }
-    } else if (D1CXX->getNumBases() > 0) {
-      if (Context.Complain) {
-        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-          << Context.C2.getTypeDeclType(D2);
-        const CXXBaseSpecifier *Base1 = D1CXX->bases_begin();
-        Context.Diag1(Base1->getLocStart(), diag::note_odr_base)
-          << Base1->getType()
-          << Base1->getSourceRange();
-        Context.Diag2(D2->getLocation(), diag::note_odr_missing_base);
-      }
-      return false;
-    }
-  }
-  
-  // Check the fields for consistency.
-  RecordDecl::field_iterator Field2 = D2->field_begin(),
-                             Field2End = D2->field_end();
-  for (RecordDecl::field_iterator Field1 = D1->field_begin(),
-                                  Field1End = D1->field_end();
-       Field1 != Field1End;
-       ++Field1, ++Field2) {
-    if (Field2 == Field2End) {
-      if (Context.Complain) {
-        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-          << Context.C2.getTypeDeclType(D2);
-        Context.Diag1(Field1->getLocation(), diag::note_odr_field)
-          << Field1->getDeclName() << Field1->getType();
-        Context.Diag2(D2->getLocation(), diag::note_odr_missing_field);
-      }
-      return false;
-    }
-    
-    if (!IsStructurallyEquivalent(Context, *Field1, *Field2))
-      return false;    
-  }
-  
-  if (Field2 != Field2End) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-        << Context.C2.getTypeDeclType(D2);
-      Context.Diag2(Field2->getLocation(), diag::note_odr_field)
-        << Field2->getDeclName() << Field2->getType();
-      Context.Diag1(D1->getLocation(), diag::note_odr_missing_field);
-    }
-    return false;
-  }
-  
-  return true;
-}
-     
-/// \brief Determine structural equivalence of two enums.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     EnumDecl *D1, EnumDecl *D2) {
-  EnumDecl::enumerator_iterator EC2 = D2->enumerator_begin(),
-                             EC2End = D2->enumerator_end();
-  for (EnumDecl::enumerator_iterator EC1 = D1->enumerator_begin(),
-                                  EC1End = D1->enumerator_end();
-       EC1 != EC1End; ++EC1, ++EC2) {
-    if (EC2 == EC2End) {
-      if (Context.Complain) {
-        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-          << Context.C2.getTypeDeclType(D2);
-        Context.Diag1(EC1->getLocation(), diag::note_odr_enumerator)
-          << EC1->getDeclName() 
-          << EC1->getInitVal().toString(10);
-        Context.Diag2(D2->getLocation(), diag::note_odr_missing_enumerator);
-      }
-      return false;
-    }
-    
-    llvm::APSInt Val1 = EC1->getInitVal();
-    llvm::APSInt Val2 = EC2->getInitVal();
-    if (!llvm::APSInt::isSameValue(Val1, Val2) || 
-        !IsStructurallyEquivalent(EC1->getIdentifier(), EC2->getIdentifier())) {
-      if (Context.Complain) {
-        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-          << Context.C2.getTypeDeclType(D2);
-        Context.Diag2(EC2->getLocation(), diag::note_odr_enumerator)
-          << EC2->getDeclName() 
-          << EC2->getInitVal().toString(10);
-        Context.Diag1(EC1->getLocation(), diag::note_odr_enumerator)
-          << EC1->getDeclName() 
-          << EC1->getInitVal().toString(10);
-      }
-      return false;
-    }
-  }
-  
-  if (EC2 != EC2End) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
-        << Context.C2.getTypeDeclType(D2);
-      Context.Diag2(EC2->getLocation(), diag::note_odr_enumerator)
-        << EC2->getDeclName() 
-        << EC2->getInitVal().toString(10);
-      Context.Diag1(D1->getLocation(), diag::note_odr_missing_enumerator);
-    }
-    return false;
-  }
-  
-  return true;
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     TemplateParameterList *Params1,
-                                     TemplateParameterList *Params2) {
-  if (Params1->size() != Params2->size()) {
-    if (Context.Complain) {
-      Context.Diag2(Params2->getTemplateLoc(), 
-                    diag::err_odr_different_num_template_parameters)
-        << Params1->size() << Params2->size();
-      Context.Diag1(Params1->getTemplateLoc(), 
-                    diag::note_odr_template_parameter_list);
-    }
-    return false;
-  }
-  
-  for (unsigned I = 0, N = Params1->size(); I != N; ++I) {
-    if (Params1->getParam(I)->getKind() != Params2->getParam(I)->getKind()) {
-      if (Context.Complain) {
-        Context.Diag2(Params2->getParam(I)->getLocation(), 
-                      diag::err_odr_different_template_parameter_kind);
-        Context.Diag1(Params1->getParam(I)->getLocation(),
-                      diag::note_odr_template_parameter_here);
-      }
-      return false;
-    }
-    
-    if (!Context.IsStructurallyEquivalent(Params1->getParam(I),
-                                          Params2->getParam(I))) {
-      
-      return false;
-    }
-  }
-  
-  return true;
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     TemplateTypeParmDecl *D1,
-                                     TemplateTypeParmDecl *D2) {
-  if (D1->isParameterPack() != D2->isParameterPack()) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(), diag::err_odr_parameter_pack_non_pack)
-        << D2->isParameterPack();
-      Context.Diag1(D1->getLocation(), diag::note_odr_parameter_pack_non_pack)
-        << D1->isParameterPack();
-    }
-    return false;
-  }
-  
-  return true;
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     NonTypeTemplateParmDecl *D1,
-                                     NonTypeTemplateParmDecl *D2) {
-  if (D1->isParameterPack() != D2->isParameterPack()) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(), diag::err_odr_parameter_pack_non_pack)
-        << D2->isParameterPack();
-      Context.Diag1(D1->getLocation(), diag::note_odr_parameter_pack_non_pack)
-        << D1->isParameterPack();
-    }
-    return false;
-  }
-  
-  // Check types.
-  if (!Context.IsStructurallyEquivalent(D1->getType(), D2->getType())) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(),
-                    diag::err_odr_non_type_parameter_type_inconsistent)
-        << D2->getType() << D1->getType();
-      Context.Diag1(D1->getLocation(), diag::note_odr_value_here)
-        << D1->getType();
-    }
-    return false;
-  }
-  
-  return true;
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     TemplateTemplateParmDecl *D1,
-                                     TemplateTemplateParmDecl *D2) {
-  if (D1->isParameterPack() != D2->isParameterPack()) {
-    if (Context.Complain) {
-      Context.Diag2(D2->getLocation(), diag::err_odr_parameter_pack_non_pack)
-        << D2->isParameterPack();
-      Context.Diag1(D1->getLocation(), diag::note_odr_parameter_pack_non_pack)
-        << D1->isParameterPack();
-    }
-    return false;
-  }
-
-  // Check template parameter lists.
-  return IsStructurallyEquivalent(Context, D1->getTemplateParameters(),
-                                  D2->getTemplateParameters());
-}
-
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     ClassTemplateDecl *D1, 
-                                     ClassTemplateDecl *D2) {
-  // Check template parameters.
-  if (!IsStructurallyEquivalent(Context,
-                                D1->getTemplateParameters(),
-                                D2->getTemplateParameters()))
-    return false;
-  
-  // Check the templated declaration.
-  return Context.IsStructurallyEquivalent(D1->getTemplatedDecl(), 
-                                          D2->getTemplatedDecl());
-}
-
-/// \brief Determine structural equivalence of two declarations.
-static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
-                                     Decl *D1, Decl *D2) {
-  // FIXME: Check for known structural equivalences via a callback of some sort.
-  
-  // Check whether we already know that these two declarations are not
-  // structurally equivalent.
-  if (Context.NonEquivalentDecls.count(std::make_pair(D1->getCanonicalDecl(),
-                                                      D2->getCanonicalDecl())))
-    return false;
-  
-  // Determine whether we've already produced a tentative equivalence for D1.
-  Decl *&EquivToD1 = Context.TentativeEquivalences[D1->getCanonicalDecl()];
-  if (EquivToD1)
-    return EquivToD1 == D2->getCanonicalDecl();
-  
-  // Produce a tentative equivalence D1 <-> D2, which will be checked later.
-  EquivToD1 = D2->getCanonicalDecl();
-  Context.DeclsToCheck.push_back(D1->getCanonicalDecl());
-  return true;
-}
-
-bool StructuralEquivalenceContext::IsStructurallyEquivalent(Decl *D1, 
-                                                            Decl *D2) {
-  if (!::IsStructurallyEquivalent(*this, D1, D2))
-    return false;
-  
-  return !Finish();
-}
-
-bool StructuralEquivalenceContext::IsStructurallyEquivalent(QualType T1, 
-                                                            QualType T2) {
-  if (!::IsStructurallyEquivalent(*this, T1, T2))
-    return false;
-  
-  return !Finish();
-}
-
-bool StructuralEquivalenceContext::Finish() {
-  while (!DeclsToCheck.empty()) {
-    // Check the next declaration.
-    Decl *D1 = DeclsToCheck.front();
-    DeclsToCheck.pop_front();
-    
-    Decl *D2 = TentativeEquivalences[D1];
-    assert(D2 && "Unrecorded tentative equivalence?");
-    
-    bool Equivalent = true;
-    
-    // FIXME: Switch on all declaration kinds. For now, we're just going to
-    // check the obvious ones.
-    if (RecordDecl *Record1 = dyn_cast<RecordDecl>(D1)) {
-      if (RecordDecl *Record2 = dyn_cast<RecordDecl>(D2)) {
-        // Check for equivalent structure names.
-        IdentifierInfo *Name1 = Record1->getIdentifier();
-        if (!Name1 && Record1->getTypedefNameForAnonDecl())
-          Name1 = Record1->getTypedefNameForAnonDecl()->getIdentifier();
-        IdentifierInfo *Name2 = Record2->getIdentifier();
-        if (!Name2 && Record2->getTypedefNameForAnonDecl())
-          Name2 = Record2->getTypedefNameForAnonDecl()->getIdentifier();
-        if (!::IsStructurallyEquivalent(Name1, Name2) ||
-            !::IsStructurallyEquivalent(*this, Record1, Record2))
-          Equivalent = false;
-      } else {
-        // Record/non-record mismatch.
-        Equivalent = false;
-      }
-    } else if (EnumDecl *Enum1 = dyn_cast<EnumDecl>(D1)) {
-      if (EnumDecl *Enum2 = dyn_cast<EnumDecl>(D2)) {
-        // Check for equivalent enum names.
-        IdentifierInfo *Name1 = Enum1->getIdentifier();
-        if (!Name1 && Enum1->getTypedefNameForAnonDecl())
-          Name1 = Enum1->getTypedefNameForAnonDecl()->getIdentifier();
-        IdentifierInfo *Name2 = Enum2->getIdentifier();
-        if (!Name2 && Enum2->getTypedefNameForAnonDecl())
-          Name2 = Enum2->getTypedefNameForAnonDecl()->getIdentifier();
-        if (!::IsStructurallyEquivalent(Name1, Name2) ||
-            !::IsStructurallyEquivalent(*this, Enum1, Enum2))
-          Equivalent = false;
-      } else {
-        // Enum/non-enum mismatch
-        Equivalent = false;
-      }
-    } else if (TypedefNameDecl *Typedef1 = dyn_cast<TypedefNameDecl>(D1)) {
-      if (TypedefNameDecl *Typedef2 = dyn_cast<TypedefNameDecl>(D2)) {
-        if (!::IsStructurallyEquivalent(Typedef1->getIdentifier(),
-                                        Typedef2->getIdentifier()) ||
-            !::IsStructurallyEquivalent(*this,
-                                        Typedef1->getUnderlyingType(),
-                                        Typedef2->getUnderlyingType()))
-          Equivalent = false;
-      } else {
-        // Typedef/non-typedef mismatch.
-        Equivalent = false;
-      }
-    } else if (ClassTemplateDecl *ClassTemplate1 
-                                           = dyn_cast<ClassTemplateDecl>(D1)) {
-      if (ClassTemplateDecl *ClassTemplate2 = dyn_cast<ClassTemplateDecl>(D2)) {
-        if (!::IsStructurallyEquivalent(ClassTemplate1->getIdentifier(),
-                                        ClassTemplate2->getIdentifier()) ||
-            !::IsStructurallyEquivalent(*this, ClassTemplate1, ClassTemplate2))
-          Equivalent = false;
-      } else {
-        // Class template/non-class-template mismatch.
-        Equivalent = false;
-      }
-    } else if (TemplateTypeParmDecl *TTP1= dyn_cast<TemplateTypeParmDecl>(D1)) {
-      if (TemplateTypeParmDecl *TTP2 = dyn_cast<TemplateTypeParmDecl>(D2)) {
-        if (!::IsStructurallyEquivalent(*this, TTP1, TTP2))
-          Equivalent = false;
-      } else {
-        // Kind mismatch.
-        Equivalent = false;
-      }
-    } else if (NonTypeTemplateParmDecl *NTTP1
-                                     = dyn_cast<NonTypeTemplateParmDecl>(D1)) {
-      if (NonTypeTemplateParmDecl *NTTP2
-                                      = dyn_cast<NonTypeTemplateParmDecl>(D2)) {
-        if (!::IsStructurallyEquivalent(*this, NTTP1, NTTP2))
-          Equivalent = false;
-      } else {
-        // Kind mismatch.
-        Equivalent = false;
-      }
-    } else if (TemplateTemplateParmDecl *TTP1
-                                  = dyn_cast<TemplateTemplateParmDecl>(D1)) {
-      if (TemplateTemplateParmDecl *TTP2
-                                    = dyn_cast<TemplateTemplateParmDecl>(D2)) {
-        if (!::IsStructurallyEquivalent(*this, TTP1, TTP2))
-          Equivalent = false;
-      } else {
-        // Kind mismatch.
-        Equivalent = false;
-      }
-    }
-    
-    if (!Equivalent) {
-      // Note that these two declarations are not equivalent (and we already
-      // know about it).
-      NonEquivalentDecls.insert(std::make_pair(D1->getCanonicalDecl(),
-                                               D2->getCanonicalDecl()));
-      return true;
-    }
-    // FIXME: Check other declaration kinds!
-  }
-  
-  return false;
-}
-
 //----------------------------------------------------------------------------
 // Import Types
 //----------------------------------------------------------------------------
 
+using namespace clang;
+
 QualType ASTNodeImporter::VisitType(const Type *T) {
   Importer.FromDiag(SourceLocation(), diag::err_unsupported_ast_node)
     << T->getTypeClassName();
@@ -2634,7 +1251,7 @@ bool ASTNodeImporter::IsStructuralMatch(ClassTemplateDecl *From,
   StructuralEquivalenceContext Ctx(Importer.getFromContext(),
                                    Importer.getToContext(),
                                    Importer.getNonEquivalentDecls());
-  return Ctx.IsStructurallyEquivalent(From, To);  
+  return Ctx.IsStructurallyEquivalent(From, To);
 }
 
 bool ASTNodeImporter::IsStructuralMatch(VarTemplateDecl *From,
@@ -2813,10 +1430,10 @@ Decl *ASTNodeImporter::VisitTypedefNameDecl(TypedefNameDecl *D, bool IsAlias) {
                                             FoundTypedef->getUnderlyingType()))
           return Importer.Imported(D, FoundTypedef);
       }
-      
+
       ConflictingDecls.push_back(FoundDecls[I]);
     }
-    
+
     if (!ConflictingDecls.empty()) {
       Name = Importer.HandleNameConflict(Name, DC, IDNS,
                                          ConflictingDecls.data(), 
@@ -2825,7 +1442,7 @@ Decl *ASTNodeImporter::VisitTypedefNameDecl(TypedefNameDecl *D, bool IsAlias) {
         return nullptr;
     }
   }
-  
+
   // Import the underlying type of this typedef;
   QualType T = Importer.Import(D->getUnderlyingType());
   if (T.isNull())
@@ -2845,12 +1462,12 @@ Decl *ASTNodeImporter::VisitTypedefNameDecl(TypedefNameDecl *D, bool IsAlias) {
                                     StartL, Loc,
                                     Name.getAsIdentifierInfo(),
                                     TInfo);
-  
+
   ToTypedef->setAccess(D->getAccess());
   ToTypedef->setLexicalDeclContext(LexicalDC);
   Importer.Imported(D, ToTypedef);
   LexicalDC->addDeclInternal(ToTypedef);
-  
+
   return ToTypedef;
 }
 
@@ -3024,9 +1641,10 @@ Decl *ASTNodeImporter::VisitRecordDecl(RecordDecl *D) {
             FoundRecord->isAnonymousStructOrUnion()) {
           // If both anonymous structs/unions are in a record context, make sure
           // they occur in the same location in the context records.
-          if (Optional<unsigned> Index1
-              = findUntaggedStructOrUnionIndex(D)) {
-            if (Optional<unsigned> Index2 =
+          if (Optional<unsigned> Index1 =
+                  StructuralEquivalenceContext::findUntaggedStructOrUnionIndex(
+                      D)) {
+            if (Optional<unsigned> Index2 = StructuralEquivalenceContext::
                     findUntaggedStructOrUnionIndex(FoundRecord)) {
               if (*Index1 != *Index2)
                 continue;
@@ -3216,7 +1834,7 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
     for (unsigned I = 0, N = FoundDecls.size(); I != N; ++I) {
       if (!FoundDecls[I]->isInIdentifierNamespace(IDNS))
         continue;
-    
+
       if (FunctionDecl *FoundFunction = dyn_cast<FunctionDecl>(FoundDecls[I])) {
         if (FoundFunction->hasExternalFormalLinkage() &&
             D->hasExternalFormalLinkage()) {
@@ -3225,14 +1843,14 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
             // FIXME: Actually try to merge the body and other attributes.
             return Importer.Imported(D, FoundFunction);
           }
-        
+
           // FIXME: Check for overloading more carefully, e.g., by boosting
           // Sema::IsOverload out to the AST library.
-          
+
           // Function overloading is okay in C++.
           if (Importer.getToContext().getLangOpts().CPlusPlus)
             continue;
-          
+
           // Complain about inconsistent function types.
           Importer.ToDiag(Loc, diag::err_odr_function_type_inconsistent)
             << Name << D->getType() << FoundFunction->getType();
@@ -3241,10 +1859,10 @@ Decl *ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
             << FoundFunction->getType();
         }
       }
-      
+
       ConflictingDecls.push_back(FoundDecls[I]);
     }
-    
+
     if (!ConflictingDecls.empty()) {
       Name = Importer.HandleNameConflict(Name, DC, IDNS,
                                          ConflictingDecls.data(), 
@@ -3449,12 +2067,12 @@ Decl *ASTNodeImporter::VisitFieldDecl(FieldDecl *D) {
       if (!Name && getFieldIndex(D) != getFieldIndex(FoundField))
         continue;
 
-      if (Importer.IsStructurallyEquivalent(D->getType(), 
+      if (Importer.IsStructurallyEquivalent(D->getType(),
                                             FoundField->getType())) {
         Importer.Imported(D, FoundField);
         return FoundField;
       }
-      
+
       Importer.ToDiag(Loc, diag::err_odr_field_type_inconsistent)
         << Name << D->getType() << FoundField->getType();
       Importer.ToDiag(FoundField->getLocation(), diag::note_odr_value_here)
@@ -3514,7 +2132,7 @@ Decl *ASTNodeImporter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
       if (!Name && getFieldIndex(D) != getFieldIndex(FoundField))
         continue;
 
-      if (Importer.IsStructurallyEquivalent(D->getType(), 
+      if (Importer.IsStructurallyEquivalent(D->getType(),
                                             FoundField->getType(),
                                             !Name.isEmpty())) {
         Importer.Imported(D, FoundField);
@@ -3638,12 +2256,12 @@ Decl *ASTNodeImporter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
   if (ToD)
     return ToD;
 
-  // Determine whether we've already imported this ivar 
+  // Determine whether we've already imported this ivar
   SmallVector<NamedDecl *, 2> FoundDecls;
   DC->getRedeclContext()->localUncachedLookup(Name, FoundDecls);
   for (unsigned I = 0, N = FoundDecls.size(); I != N; ++I) {
     if (ObjCIvarDecl *FoundIvar = dyn_cast<ObjCIvarDecl>(FoundDecls[I])) {
-      if (Importer.IsStructurallyEquivalent(D->getType(), 
+      if (Importer.IsStructurallyEquivalent(D->getType(),
                                             FoundIvar->getType())) {
         Importer.Imported(D, FoundIvar);
         return FoundIvar;
@@ -3702,12 +2320,12 @@ Decl *ASTNodeImporter::VisitVarDecl(VarDecl *D) {
     for (unsigned I = 0, N = FoundDecls.size(); I != N; ++I) {
       if (!FoundDecls[I]->isInIdentifierNamespace(IDNS))
         continue;
-      
+
       if (VarDecl *FoundVar = dyn_cast<VarDecl>(FoundDecls[I])) {
         // We have found a variable that we may need to merge with. Check it.
         if (FoundVar->hasExternalFormalLinkage() &&
             D->hasExternalFormalLinkage()) {
-          if (Importer.IsStructurallyEquivalent(D->getType(), 
+          if (Importer.IsStructurallyEquivalent(D->getType(),
                                                 FoundVar->getType())) {
             MergeWithVar = FoundVar;
             break;
@@ -3931,12 +2549,12 @@ Decl *ASTNodeImporter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
       }
 
       // Check parameter types.
-      for (ObjCMethodDecl::param_iterator P = D->param_begin(), 
+      for (ObjCMethodDecl::param_iterator P = D->param_begin(),
              PEnd = D->param_end(), FoundP = FoundMethod->param_begin();
            P != PEnd; ++P, ++FoundP) {
-        if (!Importer.IsStructurallyEquivalent((*P)->getType(), 
+        if (!Importer.IsStructurallyEquivalent((*P)->getType(),
                                                (*FoundP)->getType())) {
-          Importer.FromDiag((*P)->getLocation(), 
+          Importer.FromDiag((*P)->getLocation(),
                             diag::err_odr_objc_method_param_type_inconsistent)
             << D->isInstanceMethod() << Name
             << (*P)->getType() << (*FoundP)->getType();
@@ -4542,7 +3160,7 @@ Decl *ASTNodeImporter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
     if (ObjCPropertyDecl *FoundProp
                                 = dyn_cast<ObjCPropertyDecl>(FoundDecls[I])) {
       // Check property types.
-      if (!Importer.IsStructurallyEquivalent(D->getType(), 
+      if (!Importer.IsStructurallyEquivalent(D->getType(),
                                              FoundProp->getType())) {
         Importer.ToDiag(Loc, diag::err_odr_objc_property_type_inconsistent)
           << Name << D->getType() << FoundProp->getType();
@@ -7597,7 +6215,7 @@ bool ASTImporter::IsStructurallyEquivalent(QualType From, QualType To,
    = ImportedTypes.find(From.getTypePtr());
   if (Pos != ImportedTypes.end() && ToContext.hasSameType(Import(From), To))
     return true;
-      
+
   StructuralEquivalenceContext Ctx(FromContext, ToContext, NonEquivalentDecls,
                                    false, Complain);
   return Ctx.IsStructurallyEquivalent(From, To);
diff --git a/lib/AST/ASTStructuralEquivalence.cpp b/lib/AST/ASTStructuralEquivalence.cpp
new file mode 100644
index 000000000000..8fe72eac4133
--- /dev/null
+++ b/lib/AST/ASTStructuralEquivalence.cpp
@@ -0,0 +1,1318 @@
+//===--- ASTStructuralEquivalence.cpp - -------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implement StructuralEquivalenceContext class and helper functions
+//  for layout matching.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ASTStructuralEquivalence.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTDiagnostic.h"
+#include "clang/AST/ASTImporter.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/AST/DeclVisitor.h"
+#include "clang/AST/StmtVisitor.h"
+#include "clang/AST/TypeVisitor.h"
+#include "clang/Basic/SourceManager.h"
+
+namespace {
+
+using namespace clang;
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     QualType T1, QualType T2);
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     Decl *D1, Decl *D2);
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     const TemplateArgument &Arg1,
+                                     const TemplateArgument &Arg2);
+
+/// Determine structural equivalence of two expressions.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     Expr *E1, Expr *E2) {
+  if (!E1 || !E2)
+    return E1 == E2;
+
+  // FIXME: Actually perform a structural comparison!
+  return true;
+}
+
+/// Determine whether two identifiers are equivalent.
+static bool IsStructurallyEquivalent(const IdentifierInfo *Name1,
+                                     const IdentifierInfo *Name2) {
+  if (!Name1 || !Name2)
+    return Name1 == Name2;
+
+  return Name1->getName() == Name2->getName();
+}
+
+/// Determine whether two nested-name-specifiers are equivalent.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     NestedNameSpecifier *NNS1,
+                                     NestedNameSpecifier *NNS2) {
+  if (NNS1->getKind() != NNS2->getKind())
+    return false;
+
+  NestedNameSpecifier *Prefix1 = NNS1->getPrefix(),
+                      *Prefix2 = NNS2->getPrefix();
+  if ((bool)Prefix1 != (bool)Prefix2)
+    return false;
+
+  if (Prefix1)
+    if (!IsStructurallyEquivalent(Context, Prefix1, Prefix2))
+      return false;
+
+  switch (NNS1->getKind()) {
+  case NestedNameSpecifier::Identifier:
+    return IsStructurallyEquivalent(NNS1->getAsIdentifier(),
+                                    NNS2->getAsIdentifier());
+  case NestedNameSpecifier::Namespace:
+    return IsStructurallyEquivalent(Context, NNS1->getAsNamespace(),
+                                    NNS2->getAsNamespace());
+  case NestedNameSpecifier::NamespaceAlias:
+    return IsStructurallyEquivalent(Context, NNS1->getAsNamespaceAlias(),
+                                    NNS2->getAsNamespaceAlias());
+  case NestedNameSpecifier::TypeSpec:
+  case NestedNameSpecifier::TypeSpecWithTemplate:
+    return IsStructurallyEquivalent(Context, QualType(NNS1->getAsType(), 0),
+                                    QualType(NNS2->getAsType(), 0));
+  case NestedNameSpecifier::Global:
+    return true;
+  case NestedNameSpecifier::Super:
+    return IsStructurallyEquivalent(Context, NNS1->getAsRecordDecl(),
+                                    NNS2->getAsRecordDecl());
+  }
+  return false;
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     const TemplateName &N1,
+                                     const TemplateName &N2) {
+  if (N1.getKind() != N2.getKind())
+    return false;
+  switch (N1.getKind()) {
+  case TemplateName::Template:
+    return IsStructurallyEquivalent(Context, N1.getAsTemplateDecl(),
+                                    N2.getAsTemplateDecl());
+
+  case TemplateName::OverloadedTemplate: {
+    OverloadedTemplateStorage *OS1 = N1.getAsOverloadedTemplate(),
+                              *OS2 = N2.getAsOverloadedTemplate();
+    OverloadedTemplateStorage::iterator I1 = OS1->begin(), I2 = OS2->begin(),
+                                        E1 = OS1->end(), E2 = OS2->end();
+    for (; I1 != E1 && I2 != E2; ++I1, ++I2)
+      if (!IsStructurallyEquivalent(Context, *I1, *I2))
+        return false;
+    return I1 == E1 && I2 == E2;
+  }
+
+  case TemplateName::QualifiedTemplate: {
+    QualifiedTemplateName *QN1 = N1.getAsQualifiedTemplateName(),
+                          *QN2 = N2.getAsQualifiedTemplateName();
+    return IsStructurallyEquivalent(Context, QN1->getDecl(), QN2->getDecl()) &&
+           IsStructurallyEquivalent(Context, QN1->getQualifier(),
+                                    QN2->getQualifier());
+  }
+
+  case TemplateName::DependentTemplate: {
+    DependentTemplateName *DN1 = N1.getAsDependentTemplateName(),
+                          *DN2 = N2.getAsDependentTemplateName();
+    if (!IsStructurallyEquivalent(Context, DN1->getQualifier(),
+                                  DN2->getQualifier()))
+      return false;
+    if (DN1->isIdentifier() && DN2->isIdentifier())
+      return IsStructurallyEquivalent(DN1->getIdentifier(),
+                                      DN2->getIdentifier());
+    else if (DN1->isOverloadedOperator() && DN2->isOverloadedOperator())
+      return DN1->getOperator() == DN2->getOperator();
+    return false;
+  }
+
+  case TemplateName::SubstTemplateTemplateParm: {
+    SubstTemplateTemplateParmStorage *TS1 = N1.getAsSubstTemplateTemplateParm(),
+                                     *TS2 = N2.getAsSubstTemplateTemplateParm();
+    return IsStructurallyEquivalent(Context, TS1->getParameter(),
+                                    TS2->getParameter()) &&
+           IsStructurallyEquivalent(Context, TS1->getReplacement(),
+                                    TS2->getReplacement());
+  }
+  case TemplateName::SubstTemplateTemplateParmPack: {
+    SubstTemplateTemplateParmPackStorage
+        *P1 = N1.getAsSubstTemplateTemplateParmPack(),
+        *P2 = N2.getAsSubstTemplateTemplateParmPack();
+    return IsStructurallyEquivalent(Context, P1->getArgumentPack(),
+                                    P2->getArgumentPack()) &&
+           IsStructurallyEquivalent(Context, P1->getParameterPack(),
+                                    P2->getParameterPack());
+  }
+  }
+  return false;
+}
+
+/// Determine whether two template arguments are equivalent.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     const TemplateArgument &Arg1,
+                                     const TemplateArgument &Arg2) {
+  if (Arg1.getKind() != Arg2.getKind())
+    return false;
+
+  switch (Arg1.getKind()) {
+  case TemplateArgument::Null:
+    return true;
+
+  case TemplateArgument::Type:
+    return Context.IsStructurallyEquivalent(Arg1.getAsType(), Arg2.getAsType());
+
+  case TemplateArgument::Integral:
+    if (!Context.IsStructurallyEquivalent(Arg1.getIntegralType(),
+                                          Arg2.getIntegralType()))
+      return false;
+
+    return llvm::APSInt::isSameValue(Arg1.getAsIntegral(),
+                                     Arg2.getAsIntegral());
+
+  case TemplateArgument::Declaration:
+    return Context.IsStructurallyEquivalent(Arg1.getAsDecl(), Arg2.getAsDecl());
+
+  case TemplateArgument::NullPtr:
+    return true; // FIXME: Is this correct?
+
+  case TemplateArgument::Template:
+    return IsStructurallyEquivalent(Context, Arg1.getAsTemplate(),
+                                    Arg2.getAsTemplate());
+
+  case TemplateArgument::TemplateExpansion:
+    return IsStructurallyEquivalent(Context,
+                                    Arg1.getAsTemplateOrTemplatePattern(),
+                                    Arg2.getAsTemplateOrTemplatePattern());
+
+  case TemplateArgument::Expression:
+    return IsStructurallyEquivalent(Context, Arg1.getAsExpr(),
+                                    Arg2.getAsExpr());
+
+  case TemplateArgument::Pack:
+    if (Arg1.pack_size() != Arg2.pack_size())
+      return false;
+
+    for (unsigned I = 0, N = Arg1.pack_size(); I != N; ++I)
+      if (!IsStructurallyEquivalent(Context, Arg1.pack_begin()[I],
+                                    Arg2.pack_begin()[I]))
+        return false;
+
+    return true;
+  }
+
+  llvm_unreachable("Invalid template argument kind");
+}
+
+/// Determine structural equivalence for the common part of array
+/// types.
+static bool IsArrayStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                          const ArrayType *Array1,
+                                          const ArrayType *Array2) {
+  if (!IsStructurallyEquivalent(Context, Array1->getElementType(),
+                                Array2->getElementType()))
+    return false;
+  if (Array1->getSizeModifier() != Array2->getSizeModifier())
+    return false;
+  if (Array1->getIndexTypeQualifiers() != Array2->getIndexTypeQualifiers())
+    return false;
+
+  return true;
+}
+
+/// Determine structural equivalence of two types.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     QualType T1, QualType T2) {
+  if (T1.isNull() || T2.isNull())
+    return T1.isNull() && T2.isNull();
+
+  if (!Context.StrictTypeSpelling) {
+    // We aren't being strict about token-to-token equivalence of types,
+    // so map down to the canonical type.
+    T1 = Context.FromCtx.getCanonicalType(T1);
+    T2 = Context.ToCtx.getCanonicalType(T2);
+  }
+
+  if (T1.getQualifiers() != T2.getQualifiers())
+    return false;
+
+  Type::TypeClass TC = T1->getTypeClass();
+
+  if (T1->getTypeClass() != T2->getTypeClass()) {
+    // Compare function types with prototypes vs. without prototypes as if
+    // both did not have prototypes.
+    if (T1->getTypeClass() == Type::FunctionProto &&
+        T2->getTypeClass() == Type::FunctionNoProto)
+      TC = Type::FunctionNoProto;
+    else if (T1->getTypeClass() == Type::FunctionNoProto &&
+             T2->getTypeClass() == Type::FunctionProto)
+      TC = Type::FunctionNoProto;
+    else
+      return false;
+  }
+
+  switch (TC) {
+  case Type::Builtin:
+    // FIXME: Deal with Char_S/Char_U.
+    if (cast<BuiltinType>(T1)->getKind() != cast<BuiltinType>(T2)->getKind())
+      return false;
+    break;
+
+  case Type::Complex:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<ComplexType>(T1)->getElementType(),
+                                  cast<ComplexType>(T2)->getElementType()))
+      return false;
+    break;
+
+  case Type::Adjusted:
+  case Type::Decayed:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<AdjustedType>(T1)->getOriginalType(),
+                                  cast<AdjustedType>(T2)->getOriginalType()))
+      return false;
+    break;
+
+  case Type::Pointer:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<PointerType>(T1)->getPointeeType(),
+                                  cast<PointerType>(T2)->getPointeeType()))
+      return false;
+    break;
+
+  case Type::BlockPointer:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<BlockPointerType>(T1)->getPointeeType(),
+                                  cast<BlockPointerType>(T2)->getPointeeType()))
+      return false;
+    break;
+
+  case Type::LValueReference:
+  case Type::RValueReference: {
+    const ReferenceType *Ref1 = cast<ReferenceType>(T1);
+    const ReferenceType *Ref2 = cast<ReferenceType>(T2);
+    if (Ref1->isSpelledAsLValue() != Ref2->isSpelledAsLValue())
+      return false;
+    if (Ref1->isInnerRef() != Ref2->isInnerRef())
+      return false;
+    if (!IsStructurallyEquivalent(Context, Ref1->getPointeeTypeAsWritten(),
+                                  Ref2->getPointeeTypeAsWritten()))
+      return false;
+    break;
+  }
+
+  case Type::MemberPointer: {
+    const MemberPointerType *MemPtr1 = cast<MemberPointerType>(T1);
+    const MemberPointerType *MemPtr2 = cast<MemberPointerType>(T2);
+    if (!IsStructurallyEquivalent(Context, MemPtr1->getPointeeType(),
+                                  MemPtr2->getPointeeType()))
+      return false;
+    if (!IsStructurallyEquivalent(Context, QualType(MemPtr1->getClass(), 0),
+                                  QualType(MemPtr2->getClass(), 0)))
+      return false;
+    break;
+  }
+
+  case Type::ConstantArray: {
+    const ConstantArrayType *Array1 = cast<ConstantArrayType>(T1);
+    const ConstantArrayType *Array2 = cast<ConstantArrayType>(T2);
+    if (!llvm::APInt::isSameValue(Array1->getSize(), Array2->getSize()))
+      return false;
+
+    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
+      return false;
+    break;
+  }
+
+  case Type::IncompleteArray:
+    if (!IsArrayStructurallyEquivalent(Context, cast<ArrayType>(T1),
+                                       cast<ArrayType>(T2)))
+      return false;
+    break;
+
+  case Type::VariableArray: {
+    const VariableArrayType *Array1 = cast<VariableArrayType>(T1);
+    const VariableArrayType *Array2 = cast<VariableArrayType>(T2);
+    if (!IsStructurallyEquivalent(Context, Array1->getSizeExpr(),
+                                  Array2->getSizeExpr()))
+      return false;
+
+    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
+      return false;
+
+    break;
+  }
+
+  case Type::DependentSizedArray: {
+    const DependentSizedArrayType *Array1 = cast<DependentSizedArrayType>(T1);
+    const DependentSizedArrayType *Array2 = cast<DependentSizedArrayType>(T2);
+    if (!IsStructurallyEquivalent(Context, Array1->getSizeExpr(),
+                                  Array2->getSizeExpr()))
+      return false;
+
+    if (!IsArrayStructurallyEquivalent(Context, Array1, Array2))
+      return false;
+
+    break;
+  }
+
+  case Type::DependentSizedExtVector: {
+    const DependentSizedExtVectorType *Vec1 =
+        cast<DependentSizedExtVectorType>(T1);
+    const DependentSizedExtVectorType *Vec2 =
+        cast<DependentSizedExtVectorType>(T2);
+    if (!IsStructurallyEquivalent(Context, Vec1->getSizeExpr(),
+                                  Vec2->getSizeExpr()))
+      return false;
+    if (!IsStructurallyEquivalent(Context, Vec1->getElementType(),
+                                  Vec2->getElementType()))
+      return false;
+    break;
+  }
+
+  case Type::Vector:
+  case Type::ExtVector: {
+    const VectorType *Vec1 = cast<VectorType>(T1);
+    const VectorType *Vec2 = cast<VectorType>(T2);
+    if (!IsStructurallyEquivalent(Context, Vec1->getElementType(),
+                                  Vec2->getElementType()))
+      return false;
+    if (Vec1->getNumElements() != Vec2->getNumElements())
+      return false;
+    if (Vec1->getVectorKind() != Vec2->getVectorKind())
+      return false;
+    break;
+  }
+
+  case Type::FunctionProto: {
+    const FunctionProtoType *Proto1 = cast<FunctionProtoType>(T1);
+    const FunctionProtoType *Proto2 = cast<FunctionProtoType>(T2);
+    if (Proto1->getNumParams() != Proto2->getNumParams())
+      return false;
+    for (unsigned I = 0, N = Proto1->getNumParams(); I != N; ++I) {
+      if (!IsStructurallyEquivalent(Context, Proto1->getParamType(I),
+                                    Proto2->getParamType(I)))
+        return false;
+    }
+    if (Proto1->isVariadic() != Proto2->isVariadic())
+      return false;
+    if (Proto1->getExceptionSpecType() != Proto2->getExceptionSpecType())
+      return false;
+    if (Proto1->getExceptionSpecType() == EST_Dynamic) {
+      if (Proto1->getNumExceptions() != Proto2->getNumExceptions())
+        return false;
+      for (unsigned I = 0, N = Proto1->getNumExceptions(); I != N; ++I) {
+        if (!IsStructurallyEquivalent(Context, Proto1->getExceptionType(I),
+                                      Proto2->getExceptionType(I)))
+          return false;
+      }
+    } else if (Proto1->getExceptionSpecType() == EST_ComputedNoexcept) {
+      if (!IsStructurallyEquivalent(Context, Proto1->getNoexceptExpr(),
+                                    Proto2->getNoexceptExpr()))
+        return false;
+    }
+    if (Proto1->getTypeQuals() != Proto2->getTypeQuals())
+      return false;
+
+    // Fall through to check the bits common with FunctionNoProtoType.
+  }
+
+  case Type::FunctionNoProto: {
+    const FunctionType *Function1 = cast<FunctionType>(T1);
+    const FunctionType *Function2 = cast<FunctionType>(T2);
+    if (!IsStructurallyEquivalent(Context, Function1->getReturnType(),
+                                  Function2->getReturnType()))
+      return false;
+    if (Function1->getExtInfo() != Function2->getExtInfo())
+      return false;
+    break;
+  }
+
+  case Type::UnresolvedUsing:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<UnresolvedUsingType>(T1)->getDecl(),
+                                  cast<UnresolvedUsingType>(T2)->getDecl()))
+      return false;
+
+    break;
+
+  case Type::Attributed:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<AttributedType>(T1)->getModifiedType(),
+                                  cast<AttributedType>(T2)->getModifiedType()))
+      return false;
+    if (!IsStructurallyEquivalent(
+            Context, cast<AttributedType>(T1)->getEquivalentType(),
+            cast<AttributedType>(T2)->getEquivalentType()))
+      return false;
+    break;
+
+  case Type::Paren:
+    if (!IsStructurallyEquivalent(Context, cast<ParenType>(T1)->getInnerType(),
+                                  cast<ParenType>(T2)->getInnerType()))
+      return false;
+    break;
+
+  case Type::Typedef:
+    if (!IsStructurallyEquivalent(Context, cast<TypedefType>(T1)->getDecl(),
+                                  cast<TypedefType>(T2)->getDecl()))
+      return false;
+    break;
+
+  case Type::TypeOfExpr:
+    if (!IsStructurallyEquivalent(
+            Context, cast<TypeOfExprType>(T1)->getUnderlyingExpr(),
+            cast<TypeOfExprType>(T2)->getUnderlyingExpr()))
+      return false;
+    break;
+
+  case Type::TypeOf:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<TypeOfType>(T1)->getUnderlyingType(),
+                                  cast<TypeOfType>(T2)->getUnderlyingType()))
+      return false;
+    break;
+
+  case Type::UnaryTransform:
+    if (!IsStructurallyEquivalent(
+            Context, cast<UnaryTransformType>(T1)->getUnderlyingType(),
+            cast<UnaryTransformType>(T1)->getUnderlyingType()))
+      return false;
+    break;
+
+  case Type::Decltype:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<DecltypeType>(T1)->getUnderlyingExpr(),
+                                  cast<DecltypeType>(T2)->getUnderlyingExpr()))
+      return false;
+    break;
+
+  case Type::Auto:
+    if (!IsStructurallyEquivalent(Context, cast<AutoType>(T1)->getDeducedType(),
+                                  cast<AutoType>(T2)->getDeducedType()))
+      return false;
+    break;
+
+  case Type::DeducedTemplateSpecialization: {
+    auto *DT1 = cast<DeducedTemplateSpecializationType>(T1);
+    auto *DT2 = cast<DeducedTemplateSpecializationType>(T2);
+    if (!IsStructurallyEquivalent(Context, DT1->getTemplateName(),
+                                  DT2->getTemplateName()))
+      return false;
+    if (!IsStructurallyEquivalent(Context, DT1->getDeducedType(),
+                                  DT2->getDeducedType()))
+      return false;
+    break;
+  }
+
+  case Type::Record:
+  case Type::Enum:
+    if (!IsStructurallyEquivalent(Context, cast<TagType>(T1)->getDecl(),
+                                  cast<TagType>(T2)->getDecl()))
+      return false;
+    break;
+
+  case Type::TemplateTypeParm: {
+    const TemplateTypeParmType *Parm1 = cast<TemplateTypeParmType>(T1);
+    const TemplateTypeParmType *Parm2 = cast<TemplateTypeParmType>(T2);
+    if (Parm1->getDepth() != Parm2->getDepth())
+      return false;
+    if (Parm1->getIndex() != Parm2->getIndex())
+      return false;
+    if (Parm1->isParameterPack() != Parm2->isParameterPack())
+      return false;
+
+    // Names of template type parameters are never significant.
+    break;
+  }
+
+  case Type::SubstTemplateTypeParm: {
+    const SubstTemplateTypeParmType *Subst1 =
+        cast<SubstTemplateTypeParmType>(T1);
+    const SubstTemplateTypeParmType *Subst2 =
+        cast<SubstTemplateTypeParmType>(T2);
+    if (!IsStructurallyEquivalent(Context,
+                                  QualType(Subst1->getReplacedParameter(), 0),
+                                  QualType(Subst2->getReplacedParameter(), 0)))
+      return false;
+    if (!IsStructurallyEquivalent(Context, Subst1->getReplacementType(),
+                                  Subst2->getReplacementType()))
+      return false;
+    break;
+  }
+
+  case Type::SubstTemplateTypeParmPack: {
+    const SubstTemplateTypeParmPackType *Subst1 =
+        cast<SubstTemplateTypeParmPackType>(T1);
+    const SubstTemplateTypeParmPackType *Subst2 =
+        cast<SubstTemplateTypeParmPackType>(T2);
+    if (!IsStructurallyEquivalent(Context,
+                                  QualType(Subst1->getReplacedParameter(), 0),
+                                  QualType(Subst2->getReplacedParameter(), 0)))
+      return false;
+    if (!IsStructurallyEquivalent(Context, Subst1->getArgumentPack(),
+                                  Subst2->getArgumentPack()))
+      return false;
+    break;
+  }
+  case Type::TemplateSpecialization: {
+    const TemplateSpecializationType *Spec1 =
+        cast<TemplateSpecializationType>(T1);
+    const TemplateSpecializationType *Spec2 =
+        cast<TemplateSpecializationType>(T2);
+    if (!IsStructurallyEquivalent(Context, Spec1->getTemplateName(),
+                                  Spec2->getTemplateName()))
+      return false;
+    if (Spec1->getNumArgs() != Spec2->getNumArgs())
+      return false;
+    for (unsigned I = 0, N = Spec1->getNumArgs(); I != N; ++I) {
+      if (!IsStructurallyEquivalent(Context, Spec1->getArg(I),
+                                    Spec2->getArg(I)))
+        return false;
+    }
+    break;
+  }
+
+  case Type::Elaborated: {
+    const ElaboratedType *Elab1 = cast<ElaboratedType>(T1);
+    const ElaboratedType *Elab2 = cast<ElaboratedType>(T2);
+    // CHECKME: what if a keyword is ETK_None or ETK_typename ?
+    if (Elab1->getKeyword() != Elab2->getKeyword())
+      return false;
+    if (!IsStructurallyEquivalent(Context, Elab1->getQualifier(),
+                                  Elab2->getQualifier()))
+      return false;
+    if (!IsStructurallyEquivalent(Context, Elab1->getNamedType(),
+                                  Elab2->getNamedType()))
+      return false;
+    break;
+  }
+
+  case Type::InjectedClassName: {
+    const InjectedClassNameType *Inj1 = cast<InjectedClassNameType>(T1);
+    const InjectedClassNameType *Inj2 = cast<InjectedClassNameType>(T2);
+    if (!IsStructurallyEquivalent(Context,
+                                  Inj1->getInjectedSpecializationType(),
+                                  Inj2->getInjectedSpecializationType()))
+      return false;
+    break;
+  }
+
+  case Type::DependentName: {
+    const DependentNameType *Typename1 = cast<DependentNameType>(T1);
+    const DependentNameType *Typename2 = cast<DependentNameType>(T2);
+    if (!IsStructurallyEquivalent(Context, Typename1->getQualifier(),
+                                  Typename2->getQualifier()))
+      return false;
+    if (!IsStructurallyEquivalent(Typename1->getIdentifier(),
+                                  Typename2->getIdentifier()))
+      return false;
+
+    break;
+  }
+
+  case Type::DependentTemplateSpecialization: {
+    const DependentTemplateSpecializationType *Spec1 =
+        cast<DependentTemplateSpecializationType>(T1);
+    const DependentTemplateSpecializationType *Spec2 =
+        cast<DependentTemplateSpecializationType>(T2);
+    if (!IsStructurallyEquivalent(Context, Spec1->getQualifier(),
+                                  Spec2->getQualifier()))
+      return false;
+    if (!IsStructurallyEquivalent(Spec1->getIdentifier(),
+                                  Spec2->getIdentifier()))
+      return false;
+    if (Spec1->getNumArgs() != Spec2->getNumArgs())
+      return false;
+    for (unsigned I = 0, N = Spec1->getNumArgs(); I != N; ++I) {
+      if (!IsStructurallyEquivalent(Context, Spec1->getArg(I),
+                                    Spec2->getArg(I)))
+        return false;
+    }
+    break;
+  }
+
+  case Type::PackExpansion:
+    if (!IsStructurallyEquivalent(Context,
+                                  cast<PackExpansionType>(T1)->getPattern(),
+                                  cast<PackExpansionType>(T2)->getPattern()))
+      return false;
+    break;
+
+  case Type::ObjCInterface: {
+    const ObjCInterfaceType *Iface1 = cast<ObjCInterfaceType>(T1);
+    const ObjCInterfaceType *Iface2 = cast<ObjCInterfaceType>(T2);
+    if (!IsStructurallyEquivalent(Context, Iface1->getDecl(),
+                                  Iface2->getDecl()))
+      return false;
+    break;
+  }
+
+  case Type::ObjCTypeParam: {
+    const ObjCTypeParamType *Obj1 = cast<ObjCTypeParamType>(T1);
+    const ObjCTypeParamType *Obj2 = cast<ObjCTypeParamType>(T2);
+    if (!IsStructurallyEquivalent(Context, Obj1->getDecl(), Obj2->getDecl()))
+      return false;
+
+    if (Obj1->getNumProtocols() != Obj2->getNumProtocols())
+      return false;
+    for (unsigned I = 0, N = Obj1->getNumProtocols(); I != N; ++I) {
+      if (!IsStructurallyEquivalent(Context, Obj1->getProtocol(I),
+                                    Obj2->getProtocol(I)))
+        return false;
+    }
+    break;
+  }
+  case Type::ObjCObject: {
+    const ObjCObjectType *Obj1 = cast<ObjCObjectType>(T1);
+    const ObjCObjectType *Obj2 = cast<ObjCObjectType>(T2);
+    if (!IsStructurallyEquivalent(Context, Obj1->getBaseType(),
+                                  Obj2->getBaseType()))
+      return false;
+    if (Obj1->getNumProtocols() != Obj2->getNumProtocols())
+      return false;
+    for (unsigned I = 0, N = Obj1->getNumProtocols(); I != N; ++I) {
+      if (!IsStructurallyEquivalent(Context, Obj1->getProtocol(I),
+                                    Obj2->getProtocol(I)))
+        return false;
+    }
+    break;
+  }
+
+  case Type::ObjCObjectPointer: {
+    const ObjCObjectPointerType *Ptr1 = cast<ObjCObjectPointerType>(T1);
+    const ObjCObjectPointerType *Ptr2 = cast<ObjCObjectPointerType>(T2);
+    if (!IsStructurallyEquivalent(Context, Ptr1->getPointeeType(),
+                                  Ptr2->getPointeeType()))
+      return false;
+    break;
+  }
+
+  case Type::Atomic: {
+    if (!IsStructurallyEquivalent(Context, cast<AtomicType>(T1)->getValueType(),
+                                  cast<AtomicType>(T2)->getValueType()))
+      return false;
+    break;
+  }
+
+  case Type::Pipe: {
+    if (!IsStructurallyEquivalent(Context, cast<PipeType>(T1)->getElementType(),
+                                  cast<PipeType>(T2)->getElementType()))
+      return false;
+    break;
+  }
+
+  } // end switch
+
+  return true;
+}
+
+/// Determine structural equivalence of two fields.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     FieldDecl *Field1, FieldDecl *Field2) {
+  RecordDecl *Owner2 = cast<RecordDecl>(Field2->getDeclContext());
+
+  // For anonymous structs/unions, match up the anonymous struct/union type
+  // declarations directly, so that we don't go off searching for anonymous
+  // types
+  if (Field1->isAnonymousStructOrUnion() &&
+      Field2->isAnonymousStructOrUnion()) {
+    RecordDecl *D1 = Field1->getType()->castAs<RecordType>()->getDecl();
+    RecordDecl *D2 = Field2->getType()->castAs<RecordType>()->getDecl();
+    return IsStructurallyEquivalent(Context, D1, D2);
+  }
+
+  // Check for equivalent field names.
+  IdentifierInfo *Name1 = Field1->getIdentifier();
+  IdentifierInfo *Name2 = Field2->getIdentifier();
+  if (!::IsStructurallyEquivalent(Name1, Name2))
+    return false;
+
+  if (!IsStructurallyEquivalent(Context, Field1->getType(),
+                                Field2->getType())) {
+    if (Context.Complain) {
+      Context.Diag2(Owner2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+          << Context.ToCtx.getTypeDeclType(Owner2);
+      Context.Diag2(Field2->getLocation(), diag::note_odr_field)
+          << Field2->getDeclName() << Field2->getType();
+      Context.Diag1(Field1->getLocation(), diag::note_odr_field)
+          << Field1->getDeclName() << Field1->getType();
+    }
+    return false;
+  }
+
+  if (Field1->isBitField() != Field2->isBitField()) {
+    if (Context.Complain) {
+      Context.Diag2(Owner2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+          << Context.ToCtx.getTypeDeclType(Owner2);
+      if (Field1->isBitField()) {
+        Context.Diag1(Field1->getLocation(), diag::note_odr_bit_field)
+            << Field1->getDeclName() << Field1->getType()
+            << Field1->getBitWidthValue(Context.FromCtx);
+        Context.Diag2(Field2->getLocation(), diag::note_odr_not_bit_field)
+            << Field2->getDeclName();
+      } else {
+        Context.Diag2(Field2->getLocation(), diag::note_odr_bit_field)
+            << Field2->getDeclName() << Field2->getType()
+            << Field2->getBitWidthValue(Context.ToCtx);
+        Context.Diag1(Field1->getLocation(), diag::note_odr_not_bit_field)
+            << Field1->getDeclName();
+      }
+    }
+    return false;
+  }
+
+  if (Field1->isBitField()) {
+    // Make sure that the bit-fields are the same length.
+    unsigned Bits1 = Field1->getBitWidthValue(Context.FromCtx);
+    unsigned Bits2 = Field2->getBitWidthValue(Context.ToCtx);
+
+    if (Bits1 != Bits2) {
+      if (Context.Complain) {
+        Context.Diag2(Owner2->getLocation(),
+                      diag::warn_odr_tag_type_inconsistent)
+            << Context.ToCtx.getTypeDeclType(Owner2);
+        Context.Diag2(Field2->getLocation(), diag::note_odr_bit_field)
+            << Field2->getDeclName() << Field2->getType() << Bits2;
+        Context.Diag1(Field1->getLocation(), diag::note_odr_bit_field)
+            << Field1->getDeclName() << Field1->getType() << Bits1;
+      }
+      return false;
+    }
+  }
+
+  return true;
+}
+
+/// Determine structural equivalence of two records.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     RecordDecl *D1, RecordDecl *D2) {
+  if (D1->isUnion() != D2->isUnion()) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+          << Context.ToCtx.getTypeDeclType(D2);
+      Context.Diag1(D1->getLocation(), diag::note_odr_tag_kind_here)
+          << D1->getDeclName() << (unsigned)D1->getTagKind();
+    }
+    return false;
+  }
+
+  if (D1->isAnonymousStructOrUnion() && D2->isAnonymousStructOrUnion()) {
+    // If both anonymous structs/unions are in a record context, make sure
+    // they occur in the same location in the context records.
+    if (Optional<unsigned> Index1 =
+            StructuralEquivalenceContext::findUntaggedStructOrUnionIndex(D1)) {
+      if (Optional<unsigned> Index2 =
+              StructuralEquivalenceContext::findUntaggedStructOrUnionIndex(
+                  D2)) {
+        if (*Index1 != *Index2)
+          return false;
+      }
+    }
+  }
+
+  // If both declarations are class template specializations, we know
+  // the ODR applies, so check the template and template arguments.
+  ClassTemplateSpecializationDecl *Spec1 =
+      dyn_cast<ClassTemplateSpecializationDecl>(D1);
+  ClassTemplateSpecializationDecl *Spec2 =
+      dyn_cast<ClassTemplateSpecializationDecl>(D2);
+  if (Spec1 && Spec2) {
+    // Check that the specialized templates are the same.
+    if (!IsStructurallyEquivalent(Context, Spec1->getSpecializedTemplate(),
+                                  Spec2->getSpecializedTemplate()))
+      return false;
+
+    // Check that the template arguments are the same.
+    if (Spec1->getTemplateArgs().size() != Spec2->getTemplateArgs().size())
+      return false;
+
+    for (unsigned I = 0, N = Spec1->getTemplateArgs().size(); I != N; ++I)
+      if (!IsStructurallyEquivalent(Context, Spec1->getTemplateArgs().get(I),
+                                    Spec2->getTemplateArgs().get(I)))
+        return false;
+  }
+  // If one is a class template specialization and the other is not, these
+  // structures are different.
+  else if (Spec1 || Spec2)
+    return false;
+
+  // Compare the definitions of these two records. If either or both are
+  // incomplete, we assume that they are equivalent.
+  D1 = D1->getDefinition();
+  D2 = D2->getDefinition();
+  if (!D1 || !D2)
+    return true;
+
+  if (CXXRecordDecl *D1CXX = dyn_cast<CXXRecordDecl>(D1)) {
+    if (CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(D2)) {
+      if (D1CXX->getNumBases() != D2CXX->getNumBases()) {
+        if (Context.Complain) {
+          Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+              << Context.ToCtx.getTypeDeclType(D2);
+          Context.Diag2(D2->getLocation(), diag::note_odr_number_of_bases)
+              << D2CXX->getNumBases();
+          Context.Diag1(D1->getLocation(), diag::note_odr_number_of_bases)
+              << D1CXX->getNumBases();
+        }
+        return false;
+      }
+
+      // Check the base classes.
+      for (CXXRecordDecl::base_class_iterator Base1 = D1CXX->bases_begin(),
+                                              BaseEnd1 = D1CXX->bases_end(),
+                                              Base2 = D2CXX->bases_begin();
+           Base1 != BaseEnd1; ++Base1, ++Base2) {
+        if (!IsStructurallyEquivalent(Context, Base1->getType(),
+                                      Base2->getType())) {
+          if (Context.Complain) {
+            Context.Diag2(D2->getLocation(),
+                          diag::warn_odr_tag_type_inconsistent)
+                << Context.ToCtx.getTypeDeclType(D2);
+            Context.Diag2(Base2->getLocStart(), diag::note_odr_base)
+                << Base2->getType() << Base2->getSourceRange();
+            Context.Diag1(Base1->getLocStart(), diag::note_odr_base)
+                << Base1->getType() << Base1->getSourceRange();
+          }
+          return false;
+        }
+
+        // Check virtual vs. non-virtual inheritance mismatch.
+        if (Base1->isVirtual() != Base2->isVirtual()) {
+          if (Context.Complain) {
+            Context.Diag2(D2->getLocation(),
+                          diag::warn_odr_tag_type_inconsistent)
+                << Context.ToCtx.getTypeDeclType(D2);
+            Context.Diag2(Base2->getLocStart(), diag::note_odr_virtual_base)
+                << Base2->isVirtual() << Base2->getSourceRange();
+            Context.Diag1(Base1->getLocStart(), diag::note_odr_base)
+                << Base1->isVirtual() << Base1->getSourceRange();
+          }
+          return false;
+        }
+      }
+    } else if (D1CXX->getNumBases() > 0) {
+      if (Context.Complain) {
+        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+            << Context.ToCtx.getTypeDeclType(D2);
+        const CXXBaseSpecifier *Base1 = D1CXX->bases_begin();
+        Context.Diag1(Base1->getLocStart(), diag::note_odr_base)
+            << Base1->getType() << Base1->getSourceRange();
+        Context.Diag2(D2->getLocation(), diag::note_odr_missing_base);
+      }
+      return false;
+    }
+  }
+
+  // Check the fields for consistency.
+  RecordDecl::field_iterator Field2 = D2->field_begin(),
+                             Field2End = D2->field_end();
+  for (RecordDecl::field_iterator Field1 = D1->field_begin(),
+                                  Field1End = D1->field_end();
+       Field1 != Field1End; ++Field1, ++Field2) {
+    if (Field2 == Field2End) {
+      if (Context.Complain) {
+        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+            << Context.ToCtx.getTypeDeclType(D2);
+        Context.Diag1(Field1->getLocation(), diag::note_odr_field)
+            << Field1->getDeclName() << Field1->getType();
+        Context.Diag2(D2->getLocation(), diag::note_odr_missing_field);
+      }
+      return false;
+    }
+
+    if (!IsStructurallyEquivalent(Context, *Field1, *Field2))
+      return false;
+  }
+
+  if (Field2 != Field2End) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+          << Context.ToCtx.getTypeDeclType(D2);
+      Context.Diag2(Field2->getLocation(), diag::note_odr_field)
+          << Field2->getDeclName() << Field2->getType();
+      Context.Diag1(D1->getLocation(), diag::note_odr_missing_field);
+    }
+    return false;
+  }
+
+  return true;
+}
+
+/// Determine structural equivalence of two enums.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     EnumDecl *D1, EnumDecl *D2) {
+  EnumDecl::enumerator_iterator EC2 = D2->enumerator_begin(),
+                                EC2End = D2->enumerator_end();
+  for (EnumDecl::enumerator_iterator EC1 = D1->enumerator_begin(),
+                                     EC1End = D1->enumerator_end();
+       EC1 != EC1End; ++EC1, ++EC2) {
+    if (EC2 == EC2End) {
+      if (Context.Complain) {
+        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+            << Context.ToCtx.getTypeDeclType(D2);
+        Context.Diag1(EC1->getLocation(), diag::note_odr_enumerator)
+            << EC1->getDeclName() << EC1->getInitVal().toString(10);
+        Context.Diag2(D2->getLocation(), diag::note_odr_missing_enumerator);
+      }
+      return false;
+    }
+
+    llvm::APSInt Val1 = EC1->getInitVal();
+    llvm::APSInt Val2 = EC2->getInitVal();
+    if (!llvm::APSInt::isSameValue(Val1, Val2) ||
+        !IsStructurallyEquivalent(EC1->getIdentifier(), EC2->getIdentifier())) {
+      if (Context.Complain) {
+        Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+            << Context.ToCtx.getTypeDeclType(D2);
+        Context.Diag2(EC2->getLocation(), diag::note_odr_enumerator)
+            << EC2->getDeclName() << EC2->getInitVal().toString(10);
+        Context.Diag1(EC1->getLocation(), diag::note_odr_enumerator)
+            << EC1->getDeclName() << EC1->getInitVal().toString(10);
+      }
+      return false;
+    }
+  }
+
+  if (EC2 != EC2End) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(), diag::warn_odr_tag_type_inconsistent)
+          << Context.ToCtx.getTypeDeclType(D2);
+      Context.Diag2(EC2->getLocation(), diag::note_odr_enumerator)
+          << EC2->getDeclName() << EC2->getInitVal().toString(10);
+      Context.Diag1(D1->getLocation(), diag::note_odr_missing_enumerator);
+    }
+    return false;
+  }
+
+  return true;
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     TemplateParameterList *Params1,
+                                     TemplateParameterList *Params2) {
+  if (Params1->size() != Params2->size()) {
+    if (Context.Complain) {
+      Context.Diag2(Params2->getTemplateLoc(),
+                    diag::err_odr_different_num_template_parameters)
+          << Params1->size() << Params2->size();
+      Context.Diag1(Params1->getTemplateLoc(),
+                    diag::note_odr_template_parameter_list);
+    }
+    return false;
+  }
+
+  for (unsigned I = 0, N = Params1->size(); I != N; ++I) {
+    if (Params1->getParam(I)->getKind() != Params2->getParam(I)->getKind()) {
+      if (Context.Complain) {
+        Context.Diag2(Params2->getParam(I)->getLocation(),
+                      diag::err_odr_different_template_parameter_kind);
+        Context.Diag1(Params1->getParam(I)->getLocation(),
+                      diag::note_odr_template_parameter_here);
+      }
+      return false;
+    }
+
+    if (!Context.IsStructurallyEquivalent(Params1->getParam(I),
+                                          Params2->getParam(I))) {
+
+      return false;
+    }
+  }
+
+  return true;
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     TemplateTypeParmDecl *D1,
+                                     TemplateTypeParmDecl *D2) {
+  if (D1->isParameterPack() != D2->isParameterPack()) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(), diag::err_odr_parameter_pack_non_pack)
+          << D2->isParameterPack();
+      Context.Diag1(D1->getLocation(), diag::note_odr_parameter_pack_non_pack)
+          << D1->isParameterPack();
+    }
+    return false;
+  }
+
+  return true;
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     NonTypeTemplateParmDecl *D1,
+                                     NonTypeTemplateParmDecl *D2) {
+  if (D1->isParameterPack() != D2->isParameterPack()) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(), diag::err_odr_parameter_pack_non_pack)
+          << D2->isParameterPack();
+      Context.Diag1(D1->getLocation(), diag::note_odr_parameter_pack_non_pack)
+          << D1->isParameterPack();
+    }
+    return false;
+  }
+
+  // Check types.
+  if (!Context.IsStructurallyEquivalent(D1->getType(), D2->getType())) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(),
+                    diag::err_odr_non_type_parameter_type_inconsistent)
+          << D2->getType() << D1->getType();
+      Context.Diag1(D1->getLocation(), diag::note_odr_value_here)
+          << D1->getType();
+    }
+    return false;
+  }
+
+  return true;
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     TemplateTemplateParmDecl *D1,
+                                     TemplateTemplateParmDecl *D2) {
+  if (D1->isParameterPack() != D2->isParameterPack()) {
+    if (Context.Complain) {
+      Context.Diag2(D2->getLocation(), diag::err_odr_parameter_pack_non_pack)
+          << D2->isParameterPack();
+      Context.Diag1(D1->getLocation(), diag::note_odr_parameter_pack_non_pack)
+          << D1->isParameterPack();
+    }
+    return false;
+  }
+
+  // Check template parameter lists.
+  return IsStructurallyEquivalent(Context, D1->getTemplateParameters(),
+                                  D2->getTemplateParameters());
+}
+
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     ClassTemplateDecl *D1,
+                                     ClassTemplateDecl *D2) {
+  // Check template parameters.
+  if (!IsStructurallyEquivalent(Context, D1->getTemplateParameters(),
+                                D2->getTemplateParameters()))
+    return false;
+
+  // Check the templated declaration.
+  return Context.IsStructurallyEquivalent(D1->getTemplatedDecl(),
+                                          D2->getTemplatedDecl());
+}
+
+/// Determine structural equivalence of two declarations.
+static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
+                                     Decl *D1, Decl *D2) {
+  // FIXME: Check for known structural equivalences via a callback of some sort.
+
+  // Check whether we already know that these two declarations are not
+  // structurally equivalent.
+  if (Context.NonEquivalentDecls.count(
+          std::make_pair(D1->getCanonicalDecl(), D2->getCanonicalDecl())))
+    return false;
+
+  // Determine whether we've already produced a tentative equivalence for D1.
+  Decl *&EquivToD1 = Context.TentativeEquivalences[D1->getCanonicalDecl()];
+  if (EquivToD1)
+    return EquivToD1 == D2->getCanonicalDecl();
+
+  // Produce a tentative equivalence D1 <-> D2, which will be checked later.
+  EquivToD1 = D2->getCanonicalDecl();
+  Context.DeclsToCheck.push_back(D1->getCanonicalDecl());
+  return true;
+}
+} // namespace
+
+namespace clang {
+
+DiagnosticBuilder StructuralEquivalenceContext::Diag1(SourceLocation Loc,
+                                                      unsigned DiagID) {
+  assert(Complain && "Not allowed to complain");
+  if (LastDiagFromC2)
+    FromCtx.getDiagnostics().notePriorDiagnosticFrom(ToCtx.getDiagnostics());
+  LastDiagFromC2 = false;
+  return FromCtx.getDiagnostics().Report(Loc, DiagID);
+}
+
+DiagnosticBuilder StructuralEquivalenceContext::Diag2(SourceLocation Loc,
+                                                      unsigned DiagID) {
+  assert(Complain && "Not allowed to complain");
+  if (!LastDiagFromC2)
+    ToCtx.getDiagnostics().notePriorDiagnosticFrom(FromCtx.getDiagnostics());
+  LastDiagFromC2 = true;
+  return ToCtx.getDiagnostics().Report(Loc, DiagID);
+}
+
+Optional<unsigned>
+StructuralEquivalenceContext::findUntaggedStructOrUnionIndex(RecordDecl *Anon) {
+  ASTContext &Context = Anon->getASTContext();
+  QualType AnonTy = Context.getRecordType(Anon);
+
+  RecordDecl *Owner = dyn_cast<RecordDecl>(Anon->getDeclContext());
+  if (!Owner)
+    return None;
+
+  unsigned Index = 0;
+  for (const auto *D : Owner->noload_decls()) {
+    const auto *F = dyn_cast<FieldDecl>(D);
+    if (!F)
+      continue;
+
+    if (F->isAnonymousStructOrUnion()) {
+      if (Context.hasSameType(F->getType(), AnonTy))
+        break;
+      ++Index;
+      continue;
+    }
+
+    // If the field looks like this:
+    // struct { ... } A;
+    QualType FieldType = F->getType();
+    if (const auto *RecType = dyn_cast<RecordType>(FieldType)) {
+      const RecordDecl *RecDecl = RecType->getDecl();
+      if (RecDecl->getDeclContext() == Owner && !RecDecl->getIdentifier()) {
+        if (Context.hasSameType(FieldType, AnonTy))
+          break;
+        ++Index;
+        continue;
+      }
+    }
+  }
+
+  return Index;
+}
+
+bool StructuralEquivalenceContext::IsStructurallyEquivalent(Decl *D1,
+                                                            Decl *D2) {
+  if (!::IsStructurallyEquivalent(*this, D1, D2))
+    return false;
+
+  return !Finish();
+}
+
+bool StructuralEquivalenceContext::IsStructurallyEquivalent(QualType T1,
+                                                            QualType T2) {
+  if (!::IsStructurallyEquivalent(*this, T1, T2))
+    return false;
+
+  return !Finish();
+}
+
+bool StructuralEquivalenceContext::Finish() {
+  while (!DeclsToCheck.empty()) {
+    // Check the next declaration.
+    Decl *D1 = DeclsToCheck.front();
+    DeclsToCheck.pop_front();
+
+    Decl *D2 = TentativeEquivalences[D1];
+    assert(D2 && "Unrecorded tentative equivalence?");
+
+    bool Equivalent = true;
+
+    // FIXME: Switch on all declaration kinds. For now, we're just going to
+    // check the obvious ones.
+    if (RecordDecl *Record1 = dyn_cast<RecordDecl>(D1)) {
+      if (RecordDecl *Record2 = dyn_cast<RecordDecl>(D2)) {
+        // Check for equivalent structure names.
+        IdentifierInfo *Name1 = Record1->getIdentifier();
+        if (!Name1 && Record1->getTypedefNameForAnonDecl())
+          Name1 = Record1->getTypedefNameForAnonDecl()->getIdentifier();
+        IdentifierInfo *Name2 = Record2->getIdentifier();
+        if (!Name2 && Record2->getTypedefNameForAnonDecl())
+          Name2 = Record2->getTypedefNameForAnonDecl()->getIdentifier();
+        if (!::IsStructurallyEquivalent(Name1, Name2) ||
+            !::IsStructurallyEquivalent(*this, Record1, Record2))
+          Equivalent = false;
+      } else {
+        // Record/non-record mismatch.
+        Equivalent = false;
+      }
+    } else if (EnumDecl *Enum1 = dyn_cast<EnumDecl>(D1)) {
+      if (EnumDecl *Enum2 = dyn_cast<EnumDecl>(D2)) {
+        // Check for equivalent enum names.
+        IdentifierInfo *Name1 = Enum1->getIdentifier();
+        if (!Name1 && Enum1->getTypedefNameForAnonDecl())
+          Name1 = Enum1->getTypedefNameForAnonDecl()->getIdentifier();
+        IdentifierInfo *Name2 = Enum2->getIdentifier();
+        if (!Name2 && Enum2->getTypedefNameForAnonDecl())
+          Name2 = Enum2->getTypedefNameForAnonDecl()->getIdentifier();
+        if (!::IsStructurallyEquivalent(Name1, Name2) ||
+            !::IsStructurallyEquivalent(*this, Enum1, Enum2))
+          Equivalent = false;
+      } else {
+        // Enum/non-enum mismatch
+        Equivalent = false;
+      }
+    } else if (TypedefNameDecl *Typedef1 = dyn_cast<TypedefNameDecl>(D1)) {
+      if (TypedefNameDecl *Typedef2 = dyn_cast<TypedefNameDecl>(D2)) {
+        if (!::IsStructurallyEquivalent(Typedef1->getIdentifier(),
+                                        Typedef2->getIdentifier()) ||
+            !::IsStructurallyEquivalent(*this, Typedef1->getUnderlyingType(),
+                                        Typedef2->getUnderlyingType()))
+          Equivalent = false;
+      } else {
+        // Typedef/non-typedef mismatch.
+        Equivalent = false;
+      }
+    } else if (ClassTemplateDecl *ClassTemplate1 =
+                   dyn_cast<ClassTemplateDecl>(D1)) {
+      if (ClassTemplateDecl *ClassTemplate2 = dyn_cast<ClassTemplateDecl>(D2)) {
+        if (!::IsStructurallyEquivalent(ClassTemplate1->getIdentifier(),
+                                        ClassTemplate2->getIdentifier()) ||
+            !::IsStructurallyEquivalent(*this, ClassTemplate1, ClassTemplate2))
+          Equivalent = false;
+      } else {
+        // Class template/non-class-template mismatch.
+        Equivalent = false;
+      }
+    } else if (TemplateTypeParmDecl *TTP1 =
+                   dyn_cast<TemplateTypeParmDecl>(D1)) {
+      if (TemplateTypeParmDecl *TTP2 = dyn_cast<TemplateTypeParmDecl>(D2)) {
+        if (!::IsStructurallyEquivalent(*this, TTP1, TTP2))
+          Equivalent = false;
+      } else {
+        // Kind mismatch.
+        Equivalent = false;
+      }
+    } else if (NonTypeTemplateParmDecl *NTTP1 =
+                   dyn_cast<NonTypeTemplateParmDecl>(D1)) {
+      if (NonTypeTemplateParmDecl *NTTP2 =
+              dyn_cast<NonTypeTemplateParmDecl>(D2)) {
+        if (!::IsStructurallyEquivalent(*this, NTTP1, NTTP2))
+          Equivalent = false;
+      } else {
+        // Kind mismatch.
+        Equivalent = false;
+      }
+    } else if (TemplateTemplateParmDecl *TTP1 =
+                   dyn_cast<TemplateTemplateParmDecl>(D1)) {
+      if (TemplateTemplateParmDecl *TTP2 =
+              dyn_cast<TemplateTemplateParmDecl>(D2)) {
+        if (!::IsStructurallyEquivalent(*this, TTP1, TTP2))
+          Equivalent = false;
+      } else {
+        // Kind mismatch.
+        Equivalent = false;
+      }
+    }
+
+    if (!Equivalent) {
+      // Note that these two declarations are not equivalent (and we already
+      // know about it).
+      NonEquivalentDecls.insert(
+          std::make_pair(D1->getCanonicalDecl(), D2->getCanonicalDecl()));
+      return true;
+    }
+    // FIXME: Check other declaration kinds!
+  }
+
+  return false;
+}
+} // namespace clang
diff --git a/lib/AST/CMakeLists.txt b/lib/AST/CMakeLists.txt
index 13bf352c2f21..bbebf758212e 100644
--- a/lib/AST/CMakeLists.txt
+++ b/lib/AST/CMakeLists.txt
@@ -7,6 +7,7 @@ add_clang_library(clangAST
   ASTDiagnostic.cpp
   ASTDumper.cpp
   ASTImporter.cpp
+  ASTStructuralEquivalence.cpp
   ASTTypeTraits.cpp
   AttrImpl.cpp
   CXXInheritance.cpp
diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index cda70c5edcd4..5c2c9cbd0180 100644
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -415,6 +415,19 @@ const Attr *Decl::getDefiningAttr() const {
   return nullptr;
 }
 
+StringRef getRealizedPlatform(const AvailabilityAttr *A,
+                              const ASTContext &Context) {
+  // Check if this is an App Extension "platform", and if so chop off
+  // the suffix for matching with the actual platform.
+  StringRef RealizedPlatform = A->getPlatform()->getName();
+  if (!Context.getLangOpts().AppExt)
+    return RealizedPlatform;
+  size_t suffix = RealizedPlatform.rfind("_app_extension");
+  if (suffix != StringRef::npos)
+    return RealizedPlatform.slice(0, suffix);
+  return RealizedPlatform;
+}
+
 /// \brief Determine the availability of the given declaration based on
 /// the target platform.
 ///
@@ -434,20 +447,11 @@ static AvailabilityResult CheckAvailability(ASTContext &Context,
   if (EnclosingVersion.empty())
     return AR_Available;
 
-  // Check if this is an App Extension "platform", and if so chop off
-  // the suffix for matching with the actual platform.
   StringRef ActualPlatform = A->getPlatform()->getName();
-  StringRef RealizedPlatform = ActualPlatform;
-  if (Context.getLangOpts().AppExt) {
-    size_t suffix = RealizedPlatform.rfind("_app_extension");
-    if (suffix != StringRef::npos)
-      RealizedPlatform = RealizedPlatform.slice(0, suffix);
-  }
-
   StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
 
   // Match the platform name.
-  if (RealizedPlatform != TargetPlatform)
+  if (getRealizedPlatform(A, Context) != TargetPlatform)
     return AR_Available;
 
   StringRef PrettyPlatformName
@@ -567,6 +571,20 @@ AvailabilityResult Decl::getAvailability(std::string *Message,
   return Result;
 }
 
+VersionTuple Decl::getVersionIntroduced() const {
+  const ASTContext &Context = getASTContext();
+  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
+  for (const auto *A : attrs()) {
+    if (const auto *Availability = dyn_cast<AvailabilityAttr>(A)) {
+      if (getRealizedPlatform(Availability, Context) != TargetPlatform)
+        continue;
+      if (!Availability->getIntroduced().empty())
+        return Availability->getIntroduced();
+    }
+  }
+  return VersionTuple();
+}
+
 bool Decl::canBeWeakImported(bool &IsDefinition) const {
   IsDefinition = false;
 
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index 2fafa4876758..4d0805323e56 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -148,7 +148,8 @@ namespace {
   static unsigned
   findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base,
                            ArrayRef<APValue::LValuePathEntry> Path,
-                           uint64_t &ArraySize, QualType &Type, bool &IsArray) {
+                           uint64_t &ArraySize, QualType &Type, bool &IsArray,
+                           bool &IsUnsizedArray) {
     // This only accepts LValueBases from APValues, and APValues don't support
     // arrays that lack size info.
     assert(!isBaseAnAllocSizeCall(Base) &&
@@ -157,28 +158,34 @@ namespace {
     Type = getType(Base);
 
     for (unsigned I = 0, N = Path.size(); I != N; ++I) {
-      if (Type->isArrayType()) {
-        const ConstantArrayType *CAT =
-            cast<ConstantArrayType>(Ctx.getAsArrayType(Type));
-        Type = CAT->getElementType();
-        ArraySize = CAT->getSize().getZExtValue();
+      if (auto AT = Ctx.getAsArrayType(Type)) {
         MostDerivedLength = I + 1;
         IsArray = true;
+        if (auto CAT = Ctx.getAsConstantArrayType(Type))
+          ArraySize = CAT->getSize().getZExtValue();
+        else {
+          ArraySize = 0;
+          IsUnsizedArray = true;
+        }
+        Type = AT->getElementType();
       } else if (Type->isAnyComplexType()) {
         const ComplexType *CT = Type->castAs<ComplexType>();
         Type = CT->getElementType();
         ArraySize = 2;
         MostDerivedLength = I + 1;
         IsArray = true;
+        IsUnsizedArray = false;
       } else if (const FieldDecl *FD = getAsField(Path[I])) {
         Type = FD->getType();
         ArraySize = 0;
         MostDerivedLength = I + 1;
         IsArray = false;
+        IsUnsizedArray = false;
       } else {
         // Path[I] describes a base class.
         ArraySize = 0;
         IsArray = false;
+        IsUnsizedArray = false;
       }
     }
     return MostDerivedLength;
@@ -200,8 +207,9 @@ namespace {
     /// Is this a pointer one past the end of an object?
     unsigned IsOnePastTheEnd : 1;
 
-    /// Indicator of whether the first entry is an unsized array.
-    unsigned FirstEntryIsAnUnsizedArray : 1;
+    /// Indicator of whether the most-derived object is an unsized array (e.g.
+    /// of unknown bound).
+    unsigned MostDerivedIsAnUnsizedArray : 1;
 
     /// Indicator of whether the most-derived object is an array element.
     unsigned MostDerivedIsArrayElement : 1;
@@ -231,25 +239,28 @@ namespace {
 
     explicit SubobjectDesignator(QualType T)
         : Invalid(false), IsOnePastTheEnd(false),
-          FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
+          MostDerivedIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
           MostDerivedPathLength(0), MostDerivedArraySize(0),
           MostDerivedType(T) {}
 
     SubobjectDesignator(ASTContext &Ctx, const APValue &V)
         : Invalid(!V.isLValue() || !V.hasLValuePath()), IsOnePastTheEnd(false),
-          FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
+          MostDerivedIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
           MostDerivedPathLength(0), MostDerivedArraySize(0) {
       assert(V.isLValue() && "Non-LValue used to make an LValue designator?");
       if (!Invalid) {
         IsOnePastTheEnd = V.isLValueOnePastTheEnd();
         ArrayRef<PathEntry> VEntries = V.getLValuePath();
         Entries.insert(Entries.end(), VEntries.begin(), VEntries.end());
-        if (V.getLValueBase()) {
-          bool IsArray = false;
+        if (auto Base = V.getLValueBase()) {
+          if (auto Decl = Base.dyn_cast<ValueDecl const*>())
+            Base = cast<ValueDecl>(Decl->getMostRecentDecl());
+          bool IsArray = false, IsUnsizedArray = false;
           MostDerivedPathLength = findMostDerivedSubobject(
-              Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize,
-              MostDerivedType, IsArray);
-          MostDerivedIsArrayElement = IsArray;
+              Ctx, Base, V.getLValuePath(), MostDerivedArraySize,
+              MostDerivedType, IsArray, IsUnsizedArray);
+              MostDerivedIsArrayElement = IsArray;
+              MostDerivedIsAnUnsizedArray = IsUnsizedArray;
         }
       }
     }
@@ -263,7 +274,7 @@ namespace {
     /// known bound.
     bool isMostDerivedAnUnsizedArray() const {
       assert(!Invalid && "Calling this makes no sense on invalid designators");
-      return Entries.size() == 1 && FirstEntryIsAnUnsizedArray;
+      return MostDerivedIsAnUnsizedArray;
     }
 
     /// Determine what the most derived array's size is. Results in an assertion
@@ -303,6 +314,7 @@ namespace {
       // This is a most-derived object.
       MostDerivedType = CAT->getElementType();
       MostDerivedIsArrayElement = true;
+      MostDerivedIsAnUnsizedArray = false;
       MostDerivedArraySize = CAT->getSize().getZExtValue();
       MostDerivedPathLength = Entries.size();
     }
@@ -315,6 +327,7 @@ namespace {
 
       MostDerivedType = ElemTy;
       MostDerivedIsArrayElement = true;
+      MostDerivedIsAnUnsizedArray = true;
       // The value in MostDerivedArraySize is undefined in this case. So, set it
       // to an arbitrary value that's likely to loudly break things if it's
       // used.
@@ -333,6 +346,7 @@ namespace {
       if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
         MostDerivedType = FD->getType();
         MostDerivedIsArrayElement = false;
+        MostDerivedIsAnUnsizedArray = false;
         MostDerivedArraySize = 0;
         MostDerivedPathLength = Entries.size();
       }
@@ -347,53 +361,14 @@ namespace {
       // is unlikely to matter.
       MostDerivedType = EltTy;
       MostDerivedIsArrayElement = true;
+      MostDerivedIsAnUnsizedArray = false;
       MostDerivedArraySize = 2;
       MostDerivedPathLength = Entries.size();
     }
     void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E,
                                    const APSInt &N);
     /// Add N to the address of this subobject.
-    void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) {
-      if (Invalid || !N) return;
-      uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue();
-      if (isMostDerivedAnUnsizedArray()) {
-        // Can't verify -- trust that the user is doing the right thing (or if
-        // not, trust that the caller will catch the bad behavior).
-        // FIXME: Should we reject if this overflows, at least?
-        Entries.back().ArrayIndex += TruncatedN;
-        return;
-      }
-
-      // [expr.add]p4: For the purposes of these operators, a pointer to a
-      // nonarray object behaves the same as a pointer to the first element of
-      // an array of length one with the type of the object as its element type.
-      bool IsArray = MostDerivedPathLength == Entries.size() &&
-                     MostDerivedIsArrayElement;
-      uint64_t ArrayIndex =
-          IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd;
-      uint64_t ArraySize =
-          IsArray ? getMostDerivedArraySize() : (uint64_t)1;
-
-      if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) {
-        // Calculate the actual index in a wide enough type, so we can include
-        // it in the note.
-        N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65));
-        (llvm::APInt&)N += ArrayIndex;
-        assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index");
-        diagnosePointerArithmetic(Info, E, N);
-        setInvalid();
-        return;
-      }
-
-      ArrayIndex += TruncatedN;
-      assert(ArrayIndex <= ArraySize &&
-             "bounds check succeeded for out-of-bounds index");
-
-      if (IsArray)
-        Entries.back().ArrayIndex = ArrayIndex;
-      else
-        IsOnePastTheEnd = (ArrayIndex != 0);
-    }
+    void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N);
   };
 
   /// A stack frame in the constexpr call stack.
@@ -495,7 +470,7 @@ namespace {
         // FIXME: Force the precision of the source value down so we don't
         // print digits which are usually useless (we don't really care here if
         // we truncate a digit by accident in edge cases).  Ideally,
-        // APFloat::toString would automatically print the shortest 
+        // APFloat::toString would automatically print the shortest
         // representation which rounds to the correct value, but it's a bit
         // tricky to implement.
         unsigned precision =
@@ -720,7 +695,7 @@ namespace {
   private:
     OptionalDiagnostic Diag(SourceLocation Loc, diag::kind DiagId,
                             unsigned ExtraNotes, bool IsCCEDiag) {
-    
+
       if (EvalStatus.Diag) {
         // If we have a prior diagnostic, it will be noting that the expression
         // isn't a constant expression. This diagnostic is more important,
@@ -773,7 +748,7 @@ namespace {
           unsigned ExtraNotes = 0) {
       return Diag(Loc, DiagId, ExtraNotes, false);
     }
-    
+
     OptionalDiagnostic FFDiag(const Expr *E, diag::kind DiagId
                               = diag::note_invalid_subexpr_in_const_expr,
                             unsigned ExtraNotes = 0) {
@@ -1086,6 +1061,53 @@ void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info,
   setInvalid();
 }
 
+void SubobjectDesignator::adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) {
+  if (Invalid || !N) return;
+
+  uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue();
+  if (isMostDerivedAnUnsizedArray()) {
+    // If we're dealing with an array without constant bound, the expression is
+    // not a constant expression.
+    if (!Info.checkingPotentialConstantExpression())
+      Info.CCEDiag(E, diag::note_constexpr_array_unknown_bound_arithmetic);
+    // Can't verify -- trust that the user is doing the right thing (or if
+    // not, trust that the caller will catch the bad behavior).
+    // FIXME: Should we reject if this overflows, at least?
+    Entries.back().ArrayIndex += TruncatedN;
+    return;
+  }
+
+  // [expr.add]p4: For the purposes of these operators, a pointer to a
+  // nonarray object behaves the same as a pointer to the first element of
+  // an array of length one with the type of the object as its element type.
+  bool IsArray = MostDerivedPathLength == Entries.size() &&
+                 MostDerivedIsArrayElement;
+  uint64_t ArrayIndex =
+      IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd;
+  uint64_t ArraySize =
+      IsArray ? getMostDerivedArraySize() : (uint64_t)1;
+
+  if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) {
+    // Calculate the actual index in a wide enough type, so we can include
+    // it in the note.
+    N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65));
+    (llvm::APInt&)N += ArrayIndex;
+    assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index");
+    diagnosePointerArithmetic(Info, E, N);
+    setInvalid();
+    return;
+  }
+
+  ArrayIndex += TruncatedN;
+  assert(ArrayIndex <= ArraySize &&
+         "bounds check succeeded for out-of-bounds index");
+
+  if (IsArray)
+    Entries.back().ArrayIndex = ArrayIndex;
+  else
+    IsOnePastTheEnd = (ArrayIndex != 0);
+}
+
 CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
                                const FunctionDecl *Callee, const LValue *This,
                                APValue *Arguments)
@@ -1214,8 +1236,6 @@ namespace {
                     IsNullPtr);
       else {
         assert(!InvalidBase && "APValues can't handle invalid LValue bases");
-        assert(!Designator.FirstEntryIsAnUnsizedArray &&
-               "Unsized array with a valid base?");
         V = APValue(Base, Offset, Designator.Entries,
                     Designator.IsOnePastTheEnd, CallIndex, IsNullPtr);
       }
@@ -1280,12 +1300,9 @@ namespace {
       if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base))
         Designator.addDeclUnchecked(D, Virtual);
     }
-    void addUnsizedArray(EvalInfo &Info, QualType ElemTy) {
-      assert(Designator.Entries.empty() && getType(Base)->isPointerType());
-      assert(isBaseAnAllocSizeCall(Base) &&
-             "Only alloc_size bases can have unsized arrays");
-      Designator.FirstEntryIsAnUnsizedArray = true;
-      Designator.addUnsizedArrayUnchecked(ElemTy);
+    void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) {
+      if (checkSubobject(Info, E, CSK_ArrayToPointer))
+        Designator.addUnsizedArrayUnchecked(ElemTy);
     }
     void addArray(EvalInfo &Info, const Expr *E, const ConstantArrayType *CAT) {
       if (checkSubobject(Info, E, CSK_ArrayToPointer))
@@ -3016,6 +3033,15 @@ static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
 
     if (!evaluateVarDeclInit(Info, E, VD, Frame, BaseVal))
       return CompleteObject();
+
+    // The complete object can be an array of unknown bound, in which case we
+    // have to find the most recent declaration and adjust the type accordingly.
+    if (Info.Ctx.getAsIncompleteArrayType(BaseType)) {
+      QualType MostRecentType =
+         cast<ValueDecl const>(D->getMostRecentDecl())->getType();
+      if (Info.Ctx.getAsConstantArrayType(MostRecentType))
+        BaseType = MostRecentType;
+    }
   } else {
     const Expr *Base = LVal.Base.dyn_cast<const Expr*>();
 
@@ -4098,13 +4124,13 @@ static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc,
 
   if (Info.getLangOpts().CPlusPlus11) {
     const FunctionDecl *DiagDecl = Definition ? Definition : Declaration;
-    
+
     // If this function is not constexpr because it is an inherited
     // non-constexpr constructor, diagnose that directly.
     auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl);
     if (CD && CD->isInheritingConstructor()) {
       auto *Inherited = CD->getInheritedConstructor().getConstructor();
-      if (!Inherited->isConstexpr()) 
+      if (!Inherited->isConstexpr())
         DiagDecl = CD = Inherited;
     }
 
@@ -4418,8 +4444,14 @@ private:
   bool HandleConditionalOperator(const ConditionalOperator *E) {
     bool BoolResult;
     if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) {
-      if (Info.checkingPotentialConstantExpression() && Info.noteFailure())
+      if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) {
         CheckPotentialConstantConditional(E);
+        return false;
+      }
+      if (Info.noteFailure()) {
+        StmtVisitorTy::Visit(E->getTrueExpr());
+        StmtVisitorTy::Visit(E->getFalseExpr());
+      }
       return false;
     }
 
@@ -4635,7 +4667,7 @@ public:
           return false;
         This = &ThisVal;
         Args = Args.slice(1);
-      } else if (MD && MD->isLambdaStaticInvoker()) {   
+      } else if (MD && MD->isLambdaStaticInvoker()) {
         // Map the static invoker for the lambda back to the call operator.
         // Conveniently, we don't have to slice out the 'this' argument (as is
         // being done for the non-static case), since a static member function
@@ -4670,7 +4702,7 @@ public:
           FD = LambdaCallOp;
       }
 
-      
+
     } else
       return Error(E);
 
@@ -5240,14 +5272,19 @@ bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) {
   if (E->getBase()->getType()->isVectorType())
     return Error(E);
 
-  if (!evaluatePointer(E->getBase(), Result))
-    return false;
+  bool Success = true;
+  if (!evaluatePointer(E->getBase(), Result)) {
+    if (!Info.noteFailure())
+      return false;
+    Success = false;
+  }
 
   APSInt Index;
   if (!EvaluateInteger(E->getIdx(), Index, Info))
     return false;
 
-  return HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
+  return Success &&
+         HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
 }
 
 bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) {
@@ -5425,7 +5462,7 @@ static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base,
   Result.setInvalid(E);
 
   QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType();
-  Result.addUnsizedArray(Info, Pointee);
+  Result.addUnsizedArray(Info, E, Pointee);
   return true;
 }
 
@@ -5470,8 +5507,11 @@ public:
   bool VisitUnaryAddrOf(const UnaryOperator *E);
   bool VisitObjCStringLiteral(const ObjCStringLiteral *E)
       { return Success(E); }
-  bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E)
-      { return Success(E); }
+  bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
+    if (Info.noteFailure())
+      EvaluateIgnoredValue(Info, E->getSubExpr());
+    return Error(E);
+  }
   bool VisitAddrLabelExpr(const AddrLabelExpr *E)
       { return Success(E); }
   bool VisitCallExpr(const CallExpr *E);
@@ -5501,7 +5541,7 @@ public:
       // Update 'Result' to refer to the data member/field of the closure object
       // that represents the '*this' capture.
       if (!HandleLValueMember(Info, E, Result,
-                             Info.CurrentCall->LambdaThisCaptureField)) 
+                             Info.CurrentCall->LambdaThisCaptureField))
         return false;
       // If we captured '*this' by reference, replace the field with its referent.
       if (Info.CurrentCall->LambdaThisCaptureField->getType()
@@ -5642,12 +5682,18 @@ bool PointerExprEvaluator::VisitCastExpr(const CastExpr* E) {
                            Info, Result, SubExpr))
         return false;
     }
+
     // The result is a pointer to the first element of the array.
     if (const ConstantArrayType *CAT
           = Info.Ctx.getAsConstantArrayType(SubExpr->getType()))
       Result.addArray(Info, E, CAT);
-    else
-      Result.Designator.setInvalid();
+    // If the array hasn't been given a bound yet, add it as an unsized one.
+    else {
+      auto AT = Info.Ctx.getAsArrayType(SubExpr->getType());
+      assert(AT && "Array to pointer decay on non-array object?");
+      Result.addUnsizedArray(Info, E, AT->getElementType());
+    }
+
     return true;
 
   case CK_FunctionToPointerDecay:
@@ -5715,7 +5761,7 @@ bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) {
 
   Result.setInvalid(E);
   QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType();
-  Result.addUnsizedArray(Info, PointeeTy);
+  Result.addUnsizedArray(Info, E, PointeeTy);
   return true;
 }
 
@@ -6203,6 +6249,10 @@ bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
     // the initializer list.
     ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType());
     const Expr *Init = HaveInit ? E->getInit(ElementNo++) : &VIE;
+    if (Init->isValueDependent()) {
+      Success = false;
+      continue;
+    }
 
     // Temporarily override This, in case there's a CXXDefaultInitExpr in here.
     ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
@@ -6345,7 +6395,7 @@ bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) {
   if (ClosureClass->isInvalidDecl()) return false;
 
   if (Info.checkingPotentialConstantExpression()) return true;
-  
+
   const size_t NumFields =
       std::distance(ClosureClass->field_begin(), ClosureClass->field_end());
 
@@ -6364,7 +6414,7 @@ bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) {
     assert(CaptureInitIt != E->capture_init_end());
     // Get the initializer for this field
     Expr *const CurFieldInit = *CaptureInitIt++;
-    
+
     // If there is no initializer, either this is a VLA or an error has
     // occurred.
     if (!CurFieldInit)
@@ -6565,18 +6615,18 @@ VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
 
   // The number of initializers can be less than the number of
   // vector elements. For OpenCL, this can be due to nested vector
-  // initialization. For GCC compatibility, missing trailing elements 
+  // initialization. For GCC compatibility, missing trailing elements
   // should be initialized with zeroes.
   unsigned CountInits = 0, CountElts = 0;
   while (CountElts < NumElements) {
     // Handle nested vector initialization.
-    if (CountInits < NumInits 
+    if (CountInits < NumInits
         && E->getInit(CountInits)->getType()->isVectorType()) {
       APValue v;
       if (!EvaluateVector(E->getInit(CountInits), v, Info))
         return Error(E);
       unsigned vlen = v.getVectorLength();
-      for (unsigned j = 0; j < vlen; j++) 
+      for (unsigned j = 0; j < vlen; j++)
         Elements.push_back(v.getVectorElt(j));
       CountElts += vlen;
     } else if (EltTy->isIntegerType()) {
@@ -6852,7 +6902,7 @@ public:
   }
 
   bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) {
-    assert(E->getType()->isIntegralOrEnumerationType() && 
+    assert(E->getType()->isIntegralOrEnumerationType() &&
            "Invalid evaluation result.");
     assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
            "Invalid evaluation result.");
@@ -6866,7 +6916,7 @@ public:
   }
 
   bool Success(uint64_t Value, const Expr *E, APValue &Result) {
-    assert(E->getType()->isIntegralOrEnumerationType() && 
+    assert(E->getType()->isIntegralOrEnumerationType() &&
            "Invalid evaluation result.");
     Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType()));
     return true;
@@ -6942,7 +6992,7 @@ public:
     }
     return Success(Info.ArrayInitIndex, E);
   }
-    
+
   // Note, GNU defines __null as an integer, not a pointer.
   bool VisitGNUNullExpr(const GNUNullExpr *E) {
     return ZeroInitialization(E);
@@ -7306,10 +7356,8 @@ static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) {
 
   unsigned I = 0;
   QualType BaseType = getType(Base);
-  if (LVal.Designator.FirstEntryIsAnUnsizedArray) {
-    assert(isBaseAnAllocSizeCall(Base) &&
-           "Unsized array in non-alloc_size call?");
-    // If this is an alloc_size base, we should ignore the initial array index
+  // If this is an alloc_size base, we should ignore the initial array index
+  if (isBaseAnAllocSizeCall(Base)) {
     ++I;
     BaseType = BaseType->castAs<PointerType>()->getPointeeType();
   }
@@ -8096,12 +8144,12 @@ bool DataRecursiveIntBinOpEvaluator::
     Result = RHSResult.Val;
     return true;
   }
-  
+
   if (E->isLogicalOp()) {
     bool lhsResult, rhsResult;
     bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult);
     bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult);
-    
+
     if (LHSIsOK) {
       if (RHSIsOK) {
         if (E->getOpcode() == BO_LOr)
@@ -8117,26 +8165,26 @@ bool DataRecursiveIntBinOpEvaluator::
           return Success(rhsResult, E, Result);
       }
     }
-    
+
     return false;
   }
-  
+
   assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&
          E->getRHS()->getType()->isIntegralOrEnumerationType());
-  
+
   if (LHSResult.Failed || RHSResult.Failed)
     return false;
-  
+
   const APValue &LHSVal = LHSResult.Val;
   const APValue &RHSVal = RHSResult.Val;
-  
+
   // Handle cases like (unsigned long)&a + 4.
   if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) {
     Result = LHSVal;
     addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub);
     return true;
   }
-  
+
   // Handle cases like 4 + (unsigned long)&a
   if (E->getOpcode() == BO_Add &&
       RHSVal.isLValue() && LHSVal.isInt()) {
@@ -8144,7 +8192,7 @@ bool DataRecursiveIntBinOpEvaluator::
     addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false);
     return true;
   }
-  
+
   if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) {
     // Handle (intptr_t)&&A - (intptr_t)&&B.
     if (!LHSVal.getLValueOffset().isZero() ||
@@ -8183,7 +8231,7 @@ bool DataRecursiveIntBinOpEvaluator::
 
 void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
   Job &job = Queue.back();
-  
+
   switch (job.Kind) {
     case Job::AnyExprKind: {
       if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) {
@@ -8193,12 +8241,12 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
           return;
         }
       }
-      
+
       EvaluateExpr(job.E, Result);
       Queue.pop_back();
       return;
     }
-      
+
     case Job::BinOpKind: {
       const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
       bool SuppressRHSDiags = false;
@@ -8213,7 +8261,7 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
       enqueue(Bop->getRHS());
       return;
     }
-      
+
     case Job::BinOpVisitedLHSKind: {
       const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
       EvalResult RHS;
@@ -8223,7 +8271,7 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
       return;
     }
   }
-  
+
   llvm_unreachable("Invalid Job::Kind!");
 }
 
@@ -8735,7 +8783,7 @@ bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) {
       const RecordType *BaseRT = CurrentType->getAs<RecordType>();
       if (!BaseRT)
         return Error(OOE);
-      
+
       // Add the offset to the base.
       Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl()));
       break;
@@ -9913,7 +9961,8 @@ static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) {
 }
 
 static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
-                                 const ASTContext &Ctx, bool &IsConst) {
+                                 const ASTContext &Ctx, bool &IsConst,
+                                 bool IsCheckingForOverflow) {
   // Fast-path evaluations of integer literals, since we sometimes see files
   // containing vast quantities of these.
   if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) {
@@ -9929,12 +9978,12 @@ static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
     IsConst = false;
     return true;
   }
-  
+
   // FIXME: Evaluating values of large array and record types can cause
   // performance problems. Only do so in C++11 for now.
   if (Exp->isRValue() && (Exp->getType()->isArrayType() ||
                           Exp->getType()->isRecordType()) &&
-      !Ctx.getLangOpts().CPlusPlus11) {
+      !Ctx.getLangOpts().CPlusPlus11 && !IsCheckingForOverflow) {
     IsConst = false;
     return true;
   }
@@ -9949,9 +9998,9 @@ static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
 /// will be applied to the result.
 bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx) const {
   bool IsConst;
-  if (FastEvaluateAsRValue(this, Result, Ctx, IsConst))
+  if (FastEvaluateAsRValue(this, Result, Ctx, IsConst, false))
     return IsConst;
-  
+
   EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
   return ::EvaluateAsRValue(Info, this, Result.Val);
 }
@@ -10074,7 +10123,7 @@ APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx,
 void Expr::EvaluateForOverflow(const ASTContext &Ctx) const {
   bool IsConst;
   EvalResult EvalResult;
-  if (!FastEvaluateAsRValue(this, EvalResult, Ctx, IsConst)) {
+  if (!FastEvaluateAsRValue(this, EvalResult, Ctx, IsConst, true)) {
     EvalInfo Info(Ctx, EvalResult, EvalInfo::EM_EvaluateForOverflow);
     (void)::EvaluateAsRValue(Info, this, EvalResult.Val);
   }
diff --git a/lib/AST/TypePrinter.cpp b/lib/AST/TypePrinter.cpp
index 5268a2901ad9..2be14ab62123 100644
--- a/lib/AST/TypePrinter.cpp
+++ b/lib/AST/TypePrinter.cpp
@@ -750,6 +750,8 @@ void TypePrinter::printFunctionProtoAfter(const FunctionProtoType *T,
   if (Info.getRegParm())
     OS << " __attribute__((regparm ("
        << Info.getRegParm() << ")))";
+  if (Info.getNoCallerSavedRegs())
+    OS << "__attribute__((no_caller_saved_registers))";
 
   if (unsigned quals = T->getTypeQuals()) {
     OS << ' ';
diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index d7f1793e377c..78b03b1c314a 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -117,6 +117,7 @@ static void getDarwinDefines(MacroBuilder &Builder, const LangOptions &Opts,
                              VersionTuple &PlatformMinVersion) {
   Builder.defineMacro("__APPLE_CC__", "6000");
   Builder.defineMacro("__APPLE__");
+  Builder.defineMacro("__STDC_NO_THREADS__");
   Builder.defineMacro("OBJC_NEW_PROPERTIES");
   // AddressSanitizer doesn't play well with source fortification, which is on
   // by default on Darwin.
diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 85788b427208..03883805199f 100644
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -35,7 +35,6 @@
 #include "llvm/LTO/LTOBackend.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/SubtargetFeature.h"
-#include "llvm/Object/ModuleSummaryIndexObjectFile.h"
 #include "llvm/Passes/PassBuilder.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/MemoryBuffer.h"
diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp
index 1a57b3e6608d..791a57e61f53 100644
--- a/lib/CodeGen/CGBlocks.cpp
+++ b/lib/CodeGen/CGBlocks.cpp
@@ -619,7 +619,13 @@ static void enterBlockScope(CodeGenFunction &CGF, BlockDecl *block) {
 
     // Block captures count as local values and have imprecise semantics.
     // They also can't be arrays, so need to worry about that.
-    if (dtorKind == QualType::DK_objc_strong_lifetime) {
+    //
+    // For const-qualified captures, emit clang.arc.use to ensure the captured
+    // object doesn't get released while we are still depending on its validity
+    // within the block.
+    if (VT.isConstQualified() && VT.getObjCLifetime() == Qualifiers::OCL_Strong)
+      destroyer = CodeGenFunction::emitARCIntrinsicUse;
+    else if (dtorKind == QualType::DK_objc_strong_lifetime) {
       destroyer = CodeGenFunction::destroyARCStrongImprecise;
     } else {
       destroyer = CGF.getDestroyer(dtorKind);
@@ -866,6 +872,12 @@ llvm::Value *CodeGenFunction::EmitBlockLiteral(const CGBlockInfo &blockInfo) {
     } else if (type->isReferenceType()) {
       Builder.CreateStore(src.getPointer(), blockField);
 
+    // If type is const-qualified, copy the value into the block field.
+    } else if (type.isConstQualified() &&
+               type.getObjCLifetime() == Qualifiers::OCL_Strong) {
+      llvm::Value *value = Builder.CreateLoad(src, "captured");
+      Builder.CreateStore(value, blockField);
+
     // If this is an ARC __strong block-pointer variable, don't do a
     // block copy.
     //
diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 26235257b19d..a5c43fba6d05 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -788,6 +788,7 @@ CGFunctionInfo *CGFunctionInfo::create(unsigned llvmCC,
   FI->ChainCall = chainCall;
   FI->NoReturn = info.getNoReturn();
   FI->ReturnsRetained = info.getProducesResult();
+  FI->NoCallerSavedRegs = info.getNoCallerSavedRegs();
   FI->Required = required;
   FI->HasRegParm = info.getHasRegParm();
   FI->RegParm = info.getRegParm();
@@ -1816,6 +1817,8 @@ void CodeGenModule::ConstructAttributeList(
       RetAttrs.addAttribute(llvm::Attribute::NoAlias);
     if (TargetDecl->hasAttr<ReturnsNonNullAttr>())
       RetAttrs.addAttribute(llvm::Attribute::NonNull);
+    if (TargetDecl->hasAttr<AnyX86NoCallerSavedRegistersAttr>())
+      FuncAttrs.addAttribute("no_caller_saved_registers");
 
     HasOptnone = TargetDecl->hasAttr<OptimizeNoneAttr>();
     if (auto *AllocSize = TargetDecl->getAttr<AllocSizeAttr>()) {
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index dd32a44393c6..3e5434660567 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -4034,11 +4034,9 @@ CGDebugInfo::getOrCreateNameSpace(const NamespaceDecl *NSDecl) {
   if (I != NameSpaceCache.end())
     return cast<llvm::DINamespace>(I->second);
 
-  unsigned LineNo = getLineNumber(NSDecl->getLocation());
-  llvm::DIFile *FileD = getOrCreateFile(NSDecl->getLocation());
   llvm::DIScope *Context = getDeclContextDescriptor(NSDecl);
-  llvm::DINamespace *NS = DBuilder.createNameSpace(
-      Context, NSDecl->getName(), FileD, LineNo, NSDecl->isInline());
+  llvm::DINamespace *NS =
+      DBuilder.createNameSpace(Context, NSDecl->getName(), NSDecl->isInline());
   NameSpaceCache[NSDecl].reset(NS);
   return NS;
 }
diff --git a/lib/CodeGen/CGDeclCXX.cpp b/lib/CodeGen/CGDeclCXX.cpp
index f61d60a63a6a..ff766e6b3b9c 100644
--- a/lib/CodeGen/CGDeclCXX.cpp
+++ b/lib/CodeGen/CGDeclCXX.cpp
@@ -571,9 +571,10 @@ CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn,
   FinishFunction();
 }
 
-void CodeGenFunction::GenerateCXXGlobalDtorsFunc(llvm::Function *Fn,
-                  const std::vector<std::pair<llvm::WeakVH, llvm::Constant*> >
-                                                &DtorsAndObjects) {
+void CodeGenFunction::GenerateCXXGlobalDtorsFunc(
+    llvm::Function *Fn,
+    const std::vector<std::pair<llvm::WeakTrackingVH, llvm::Constant *>>
+        &DtorsAndObjects) {
   {
     auto NL = ApplyDebugLocation::CreateEmpty(*this);
     StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index d0aacf65428f..863b4380da47 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -4065,6 +4065,8 @@ LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
 
     RValue RV = EmitAnyExpr(E->getRHS());
     LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
+    if (RV.isScalar())
+      EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
     EmitStoreThroughLValue(RV, LV);
     return LV;
   }
diff --git a/lib/CodeGen/CGObjC.cpp b/lib/CodeGen/CGObjC.cpp
index 76e7df861f74..f4fbab3c2b83 100644
--- a/lib/CodeGen/CGObjC.cpp
+++ b/lib/CodeGen/CGObjC.cpp
@@ -2415,6 +2415,12 @@ void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF,
   CGF.EmitARCDestroyWeak(addr);
 }
 
+void CodeGenFunction::emitARCIntrinsicUse(CodeGenFunction &CGF, Address addr,
+                                          QualType type) {
+  llvm::Value *value = CGF.Builder.CreateLoad(addr);
+  CGF.EmitARCIntrinsicUse(value);
+}
+
 namespace {
   struct CallObjCAutoreleasePoolObject final : EHScopeStack::Cleanup {
     llvm::Value *Token;
diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index 43b347ce353f..70d24b791334 100644
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -886,7 +886,7 @@ protected:
 
   /// Cached reference to the class for constant strings. This value has type
   /// int * but is actually an Obj-C class pointer.
-  llvm::WeakVH ConstantStringClassRef;
+  llvm::WeakTrackingVH ConstantStringClassRef;
 
   /// \brief The LLVM type corresponding to NSConstantString.
   llvm::StructType *NSConstantStringType = nullptr;
diff --git a/lib/CodeGen/CGStmtOpenMP.cpp b/lib/CodeGen/CGStmtOpenMP.cpp
index f738dd0750fa..19b6cbab66c9 100644
--- a/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/lib/CodeGen/CGStmtOpenMP.cpp
@@ -1675,7 +1675,7 @@ static void emitOMPLoopBodyWithStopPoint(CodeGenFunction &CGF,
                                          CodeGenFunction::JumpDest LoopExit) {
   CGF.EmitOMPLoopBody(S, LoopExit);
   CGF.EmitStopPoint(&S);
-};
+}
 
 void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
   auto &&CodeGen = [&S](CodeGenFunction &CGF, PrePostActionTy &) {
@@ -2093,7 +2093,7 @@ emitDistributeParallelForDispatchBounds(CodeGenFunction &CGF,
   llvm::Value *UBVal = CGF.EmitLoadOfScalar(UB, /*Volatile=*/false, IteratorTy,
                                             SourceLocation());
   return {LBVal, UBVal};
-};
+}
 
 static void emitDistributeParallelForDistributeInnerBoundParams(
     CodeGenFunction &CGF, const OMPExecutableDirective &S,
@@ -2110,7 +2110,7 @@ static void emitDistributeParallelForDistributeInnerBoundParams(
   auto UBCast = CGF.Builder.CreateIntCast(
       CGF.Builder.CreateLoad(UB.getAddress()), CGF.SizeTy, /*isSigned=*/false);
   CapturedVars.push_back(UBCast);
-};
+}
 
 static void
 emitInnerParallelForWhenCombined(CodeGenFunction &CGF,
diff --git a/lib/CodeGen/CodeGenAction.cpp b/lib/CodeGen/CodeGenAction.cpp
index b864069dc645..f57cbe86c413 100644
--- a/lib/CodeGen/CodeGenAction.cpp
+++ b/lib/CodeGen/CodeGenAction.cpp
@@ -944,7 +944,7 @@ std::unique_ptr<llvm::Module> CodeGenAction::loadModule(MemoryBufferRef MBRef) {
 
 void CodeGenAction::ExecuteAction() {
   // If this is an IR file, we have to treat it specially.
-  if (getCurrentFileKind() == IK_LLVM_IR) {
+  if (getCurrentFileKind().getLanguage() == InputKind::LLVM_IR) {
     BackendAction BA = static_cast<BackendAction>(Act);
     CompilerInstance &CI = getCompilerInstance();
     std::unique_ptr<raw_pwrite_stream> OS =
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 1ded824ba5b0..b69640894f11 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -3369,6 +3369,7 @@ public:
   static Destroyer destroyARCStrongImprecise;
   static Destroyer destroyARCStrongPrecise;
   static Destroyer destroyARCWeak;
+  static Destroyer emitARCIntrinsicUse;
 
   void EmitObjCAutoreleasePoolPop(llvm::Value *Ptr); 
   llvm::Value *EmitObjCAutoreleasePoolPush();
@@ -3470,9 +3471,10 @@ public:
 
   /// GenerateCXXGlobalDtorsFunc - Generates code for destroying global
   /// variables.
-  void GenerateCXXGlobalDtorsFunc(llvm::Function *Fn,
-                                  const std::vector<std::pair<llvm::WeakVH,
-                                  llvm::Constant*> > &DtorsAndObjects);
+  void GenerateCXXGlobalDtorsFunc(
+      llvm::Function *Fn,
+      const std::vector<std::pair<llvm::WeakTrackingVH, llvm::Constant *>>
+          &DtorsAndObjects);
 
   void GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
                                         const VarDecl *D,
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 25d32f19d0e5..10f167321454 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -369,9 +369,13 @@ void InstrProfStats::reportDiagnostics(DiagnosticsEngine &Diags,
     if (MainFile.empty())
       MainFile = "<stdin>";
     Diags.Report(diag::warn_profile_data_unprofiled) << MainFile;
-  } else
-    Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Missing
-                                                      << Mismatched;
+  } else {
+    if (Mismatched > 0)
+      Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Mismatched;
+
+    if (Missing > 0)
+      Diags.Report(diag::warn_profile_data_missing) << Visited << Missing;
+  }
 }
 
 void CodeGenModule::Release() {
@@ -1150,7 +1154,7 @@ void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) {
 }
 
 static void emitUsed(CodeGenModule &CGM, StringRef Name,
-                     std::vector<llvm::WeakVH> &List) {
+                     std::vector<llvm::WeakTrackingVH> &List) {
   // Don't create llvm.used if there is no need.
   if (List.empty())
     return;
@@ -1324,13 +1328,10 @@ void CodeGenModule::EmitDeferred() {
 
   // Grab the list of decls to emit. If EmitGlobalDefinition schedules more
   // work, it will not interfere with this.
-  std::vector<DeferredGlobal> CurDeclsToEmit;
+  std::vector<GlobalDecl> CurDeclsToEmit;
   CurDeclsToEmit.swap(DeferredDeclsToEmit);
 
-  for (DeferredGlobal &G : CurDeclsToEmit) {
-    GlobalDecl D = G.GD;
-    G.GV = nullptr;
-
+  for (GlobalDecl &D : CurDeclsToEmit) {
     // We should call GetAddrOfGlobal with IsForDefinition set to true in order
     // to get GlobalValue with exactly the type we need, not something that
     // might had been created for another decl with the same mangled name but
@@ -1707,13 +1708,13 @@ void CodeGenModule::EmitGlobal(GlobalDecl GD) {
   }
 
   StringRef MangledName = getMangledName(GD);
-  if (llvm::GlobalValue *GV = GetGlobalValue(MangledName)) {
+  if (GetGlobalValue(MangledName) != nullptr) {
     // The value has already been used and should therefore be emitted.
-    addDeferredDeclToEmit(GV, GD);
+    addDeferredDeclToEmit(GD);
   } else if (MustBeEmitted(Global)) {
     // The value must be emitted, but cannot be emitted eagerly.
     assert(!MayBeEmittedEagerly(Global));
-    addDeferredDeclToEmit(/*GV=*/nullptr, GD);
+    addDeferredDeclToEmit(GD);
   } else {
     // Otherwise, remember that we saw a deferred decl with this name.  The
     // first use of the mangled name will cause it to move into
@@ -2040,7 +2041,7 @@ llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
     if (D && isa<CXXDestructorDecl>(D) &&
         getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
                                            GD.getDtorType()))
-      addDeferredDeclToEmit(F, GD);
+      addDeferredDeclToEmit(GD);
 
     // This is the first use or definition of a mangled name.  If there is a
     // deferred decl with this name, remember that we need to emit it at the end
@@ -2050,7 +2051,7 @@ llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
       // Move the potentially referenced deferred decl to the
       // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we
       // don't need it anymore).
-      addDeferredDeclToEmit(F, DDI->second);
+      addDeferredDeclToEmit(DDI->second);
       DeferredDecls.erase(DDI);
 
       // Otherwise, there are cases we have to worry about where we're
@@ -2070,7 +2071,7 @@ llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
            FD = FD->getPreviousDecl()) {
         if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
           if (FD->doesThisDeclarationHaveABody()) {
-            addDeferredDeclToEmit(F, GD.getWithDecl(FD));
+            addDeferredDeclToEmit(GD.getWithDecl(FD));
             break;
           }
         }
@@ -2298,7 +2299,7 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName,
   if (DDI != DeferredDecls.end()) {
     // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
     // list, and remove it from DeferredDecls (since we don't need it anymore).
-    addDeferredDeclToEmit(GV, DDI->second);
+    addDeferredDeclToEmit(DDI->second);
     DeferredDecls.erase(DDI);
   }
 
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index c4985ba41db1..e38337814ebc 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -315,14 +315,9 @@ private:
 
   /// This is a list of deferred decls which we have seen that *are* actually
   /// referenced. These get code generated when the module is done.
-  struct DeferredGlobal {
-    DeferredGlobal(llvm::GlobalValue *GV, GlobalDecl GD) : GV(GV), GD(GD) {}
-    llvm::TrackingVH<llvm::GlobalValue> GV;
-    GlobalDecl GD;
-  };
-  std::vector<DeferredGlobal> DeferredDeclsToEmit;
-  void addDeferredDeclToEmit(llvm::GlobalValue *GV, GlobalDecl GD) {
-    DeferredDeclsToEmit.emplace_back(GV, GD);
+  std::vector<GlobalDecl> DeferredDeclsToEmit;
+  void addDeferredDeclToEmit(GlobalDecl GD) {
+    DeferredDeclsToEmit.emplace_back(GD);
   }
 
   /// List of alias we have emitted. Used to make sure that what they point to
@@ -349,8 +344,8 @@ private:
   /// List of global values which are required to be present in the object file;
   /// bitcast to i8*. This is used for forcing visibility of symbols which may
   /// otherwise be optimized out.
-  std::vector<llvm::WeakVH> LLVMUsed;
-  std::vector<llvm::WeakVH> LLVMCompilerUsed;
+  std::vector<llvm::WeakTrackingVH> LLVMUsed;
+  std::vector<llvm::WeakTrackingVH> LLVMCompilerUsed;
 
   /// Store the list of global constructors and their respective priorities to
   /// be emitted when the translation unit is complete.
@@ -421,7 +416,7 @@ private:
   SmallVector<GlobalInitData, 8> PrioritizedCXXGlobalInits;
 
   /// Global destructor functions and arguments that need to run on termination.
-  std::vector<std::pair<llvm::WeakVH,llvm::Constant*> > CXXGlobalDtors;
+  std::vector<std::pair<llvm::WeakTrackingVH, llvm::Constant *>> CXXGlobalDtors;
 
   /// \brief The complete set of modules that has been imported.
   llvm::SetVector<clang::Module *> ImportedModules;
@@ -438,7 +433,7 @@ private:
 
   /// Cached reference to the class for constant strings. This value has type
   /// int * but is actually an Obj-C class pointer.
-  llvm::WeakVH CFConstantStringClassRef;
+  llvm::WeakTrackingVH CFConstantStringClassRef;
 
   /// \brief The type used to describe the state of a fast enumeration in
   /// Objective-C's for..in loop.
diff --git a/lib/CodeGen/MacroPPCallbacks.cpp b/lib/CodeGen/MacroPPCallbacks.cpp
index acea5c1143cf..6a31dfe53d64 100644
--- a/lib/CodeGen/MacroPPCallbacks.cpp
+++ b/lib/CodeGen/MacroPPCallbacks.cpp
@@ -198,7 +198,8 @@ void MacroPPCallbacks::MacroDefined(const Token &MacroNameTok,
 }
 
 void MacroPPCallbacks::MacroUndefined(const Token &MacroNameTok,
-                                      const MacroDefinition &MD) {
+                                      const MacroDefinition &MD,
+                                      const MacroDirective *Undef) {
   IdentifierInfo *Id = MacroNameTok.getIdentifierInfo();
   SourceLocation location = getCorrectLocation(MacroNameTok.getLocation());
   Gen->getCGDebugInfo()->CreateMacro(getCurrentScope(),
diff --git a/lib/CodeGen/MacroPPCallbacks.h b/lib/CodeGen/MacroPPCallbacks.h
index 06217f9c5883..e117f96f47df 100644
--- a/lib/CodeGen/MacroPPCallbacks.h
+++ b/lib/CodeGen/MacroPPCallbacks.h
@@ -110,8 +110,8 @@ public:
   /// Hook called whenever a macro \#undef is seen.
   ///
   /// MD is released immediately following this callback.
-  void MacroUndefined(const Token &MacroNameTok,
-                      const MacroDefinition &MD) override;
+  void MacroUndefined(const Token &MacroNameTok, const MacroDefinition &MD,
+                      const MacroDirective *Undef) override;
 };
 
 } // end namespace clang
diff --git a/lib/Driver/Job.cpp b/lib/Driver/Job.cpp
index 7a4d055159ec..8b85680f10b1 100644
--- a/lib/Driver/Job.cpp
+++ b/lib/Driver/Job.cpp
@@ -49,7 +49,7 @@ static bool skipArgs(const char *Flag, bool HaveCrashVFS, int &SkipNum,
   // arguments.  Therefore, we need to skip the flag and the next argument.
   bool ShouldSkip = llvm::StringSwitch<bool>(Flag)
     .Cases("-MF", "-MT", "-MQ", "-serialize-diagnostic-file", true)
-    .Cases("-o", "-coverage-file", "-dependency-file", true)
+    .Cases("-o", "-dependency-file", true)
     .Cases("-fdebug-compilation-dir", "-diagnostic-log-file", true)
     .Cases("-dwarf-debug-flags", "-ivfsoverlay", true)
     .Default(false);
diff --git a/lib/Driver/ToolChains/Clang.cpp b/lib/Driver/ToolChains/Clang.cpp
index 6e1e4ccf44f0..555847aeeb23 100644
--- a/lib/Driver/ToolChains/Clang.cpp
+++ b/lib/Driver/ToolChains/Clang.cpp
@@ -2773,12 +2773,14 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // -gsplit-dwarf should turn on -g and enable the backend dwarf
   // splitting and extraction.
   // FIXME: Currently only works on Linux.
-  if (getToolChain().getTriple().isOSLinux() && SplitDwarfArg) {
+  if (getToolChain().getTriple().isOSLinux()) {
     if (!splitDwarfInlining)
       CmdArgs.push_back("-fno-split-dwarf-inlining");
-    if (DebugInfoKind == codegenoptions::NoDebugInfo)
-      DebugInfoKind = codegenoptions::LimitedDebugInfo;
-    CmdArgs.push_back("-enable-split-dwarf");
+    if (SplitDwarfArg) {
+      if (DebugInfoKind == codegenoptions::NoDebugInfo)
+        DebugInfoKind = codegenoptions::LimitedDebugInfo;
+      CmdArgs.push_back("-enable-split-dwarf");
+    }
   }
 
   // After we've dealt with all combinations of things that could
diff --git a/lib/Edit/EditedSource.cpp b/lib/Edit/EditedSource.cpp
index 5292a58a9ccd..1a7a68cffb62 100644
--- a/lib/Edit/EditedSource.cpp
+++ b/lib/Edit/EditedSource.cpp
@@ -363,13 +363,14 @@ static void adjustRemoval(const SourceManager &SM, const LangOptions &LangOpts,
 
 static void applyRewrite(EditsReceiver &receiver,
                          StringRef text, FileOffset offs, unsigned len,
-                         const SourceManager &SM, const LangOptions &LangOpts) {
+                         const SourceManager &SM, const LangOptions &LangOpts,
+                         bool shouldAdjustRemovals) {
   assert(offs.getFID().isValid());
   SourceLocation Loc = SM.getLocForStartOfFile(offs.getFID());
   Loc = Loc.getLocWithOffset(offs.getOffset());
   assert(Loc.isFileID());
 
-  if (text.empty())
+  if (text.empty() && shouldAdjustRemovals)
     adjustRemoval(SM, LangOpts, Loc, offs, len, text);
 
   CharSourceRange range = CharSourceRange::getCharRange(Loc,
@@ -387,7 +388,8 @@ static void applyRewrite(EditsReceiver &receiver,
     receiver.insert(Loc, text);
 }
 
-void EditedSource::applyRewrites(EditsReceiver &receiver) {
+void EditedSource::applyRewrites(EditsReceiver &receiver,
+                                 bool shouldAdjustRemovals) {
   SmallString<128> StrVec;
   FileOffset CurOffs, CurEnd;
   unsigned CurLen;
@@ -414,14 +416,16 @@ void EditedSource::applyRewrites(EditsReceiver &receiver) {
       continue;
     }
 
-    applyRewrite(receiver, StrVec, CurOffs, CurLen, SourceMgr, LangOpts);
+    applyRewrite(receiver, StrVec, CurOffs, CurLen, SourceMgr, LangOpts,
+                 shouldAdjustRemovals);
     CurOffs = offs;
     StrVec = act.Text;
     CurLen = act.RemoveLen;
     CurEnd = CurOffs.getWithOffset(CurLen);
   }
 
-  applyRewrite(receiver, StrVec, CurOffs, CurLen, SourceMgr, LangOpts);
+  applyRewrite(receiver, StrVec, CurOffs, CurLen, SourceMgr, LangOpts,
+               shouldAdjustRemovals);
 }
 
 void EditedSource::clearRewrites() {
diff --git a/lib/Format/UnwrappedLineParser.cpp b/lib/Format/UnwrappedLineParser.cpp
index 5be68ad5c6b8..2d788b52dfda 100644
--- a/lib/Format/UnwrappedLineParser.cpp
+++ b/lib/Format/UnwrappedLineParser.cpp
@@ -1040,13 +1040,15 @@ void UnwrappedLineParser::parseStructuralElement() {
         return;
       }
 
-      // Parse function literal unless 'function' is the first token in a line
-      // in which case this should be treated as a free-standing function.
+      // Function declarations (as opposed to function expressions) are parsed
+      // on their own unwrapped line by continuing this loop. Function
+      // expressions (functions that are not on their own line) must not create
+      // a new unwrapped line, so they are special cased below.
+      size_t TokenCount = Line->Tokens.size();
       if (Style.Language == FormatStyle::LK_JavaScript &&
-          (FormatTok->is(Keywords.kw_function) ||
-           FormatTok->startsSequence(Keywords.kw_async,
-                                     Keywords.kw_function)) &&
-          Line->Tokens.size() > 0) {
+          FormatTok->is(Keywords.kw_function) &&
+          (TokenCount > 1 || (TokenCount == 1 && !Line->Tokens.front().Tok->is(
+                                                     Keywords.kw_async)))) {
         tryToParseJSFunction();
         break;
       }
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index 2acdc6494f85..32ee9d3e9961 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -1076,9 +1076,11 @@ bool ASTUnit::Parse(std::shared_ptr<PCHContainerOperations> PCHContainerOps,
   
   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
          "Invocation must have exactly one source file!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_AST &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
+             InputKind::Source &&
          "FIXME: AST inputs not yet supported here!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_LLVM_IR &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
+             InputKind::LLVM_IR &&
          "IR inputs not support here!");
 
   // Configure the various subsystems.
@@ -1552,9 +1554,11 @@ ASTUnit::getMainBufferWithPrecompiledPreamble(
   
   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
          "Invocation must have exactly one source file!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_AST &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
+             InputKind::Source &&
          "FIXME: AST inputs not yet supported here!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_LLVM_IR &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
+             InputKind::LLVM_IR &&
          "IR inputs not support here!");
   
   // Clear out old caches and data.
@@ -1810,10 +1814,12 @@ ASTUnit *ASTUnit::LoadFromCompilerInvocationAction(
   
   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
          "Invocation must have exactly one source file!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_AST &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
+             InputKind::Source &&
          "FIXME: AST inputs not yet supported here!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_LLVM_IR &&
-         "IR inputs not supported here!");
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
+             InputKind::LLVM_IR &&
+         "IR inputs not support here!");
 
   // Configure the various subsystems.
   AST->TheSema.reset();
@@ -2399,11 +2405,12 @@ void ASTUnit::CodeComplete(
   
   assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
          "Invocation must have exactly one source file!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_AST &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getFormat() ==
+             InputKind::Source &&
          "FIXME: AST inputs not yet supported here!");
-  assert(Clang->getFrontendOpts().Inputs[0].getKind() != IK_LLVM_IR &&
+  assert(Clang->getFrontendOpts().Inputs[0].getKind().getLanguage() !=
+             InputKind::LLVM_IR &&
          "IR inputs not support here!");
-
   
   // Use the source and file managers that we were given.
   Clang->setFileManager(&FileMgr);
diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index 8b4b16920668..a7b5fa7dfd29 100644
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -858,7 +858,8 @@ bool CompilerInstance::InitializeSourceManager(
                             /*SearchPath=*/nullptr,
                             /*RelativePath=*/nullptr,
                             /*RequestingModule=*/nullptr,
-                            /*SuggestedModule=*/nullptr, /*SkipCache=*/true);
+                            /*SuggestedModule=*/nullptr, /*IsMapped=*/nullptr,
+                            /*SkipCache=*/true);
       // Also add the header to /showIncludes output.
       if (File)
         DepOpts.ShowIncludesPretendHeader = File->getName();
@@ -1015,14 +1016,14 @@ bool CompilerInstance::ExecuteAction(FrontendAction &Act) {
 
 /// \brief Determine the appropriate source input kind based on language
 /// options.
-static InputKind getSourceInputKindFromOptions(const LangOptions &LangOpts) {
+static InputKind::Language getLanguageFromOptions(const LangOptions &LangOpts) {
   if (LangOpts.OpenCL)
-    return IK_OpenCL;
+    return InputKind::OpenCL;
   if (LangOpts.CUDA)
-    return IK_CUDA;
+    return InputKind::CUDA;
   if (LangOpts.ObjC1)
-    return LangOpts.CPlusPlus? IK_ObjCXX : IK_ObjC;
-  return LangOpts.CPlusPlus? IK_CXX : IK_C;
+    return LangOpts.CPlusPlus ? InputKind::ObjCXX : InputKind::ObjC;
+  return LangOpts.CPlusPlus ? InputKind::CXX : InputKind::C;
 }
 
 /// \brief Compile a module file for the given module, using the options 
@@ -1079,10 +1080,13 @@ static bool compileModuleImpl(CompilerInstance &ImportingInstance,
   FrontendOpts.DisableFree = false;
   FrontendOpts.GenerateGlobalModuleIndex = false;
   FrontendOpts.BuildingImplicitModule = true;
+  FrontendOpts.OriginalModuleMap =
+      ModMap.getModuleMapFileForUniquing(Module)->getName();
   // Force implicitly-built modules to hash the content of the module file.
   HSOpts.ModulesHashContent = true;
   FrontendOpts.Inputs.clear();
-  InputKind IK = getSourceInputKindFromOptions(*Invocation->getLangOpts());
+  InputKind IK(getLanguageFromOptions(*Invocation->getLangOpts()),
+               InputKind::ModuleMap);
 
   // Don't free the remapped file buffers; they are owned by our caller.
   PPOpts.RetainRemappedFileBuffers = true;
@@ -1127,11 +1131,12 @@ static bool compileModuleImpl(CompilerInstance &ImportingInstance,
   if (const FileEntry *ModuleMapFile =
           ModMap.getContainingModuleMapFile(Module)) {
     // Use the module map where this module resides.
-    FrontendOpts.Inputs.emplace_back(ModuleMapFile->getName(), IK);
+    FrontendOpts.Inputs.emplace_back(ModuleMapFile->getName(), IK,
+                                     +Module->IsSystem);
   } else {
     SmallString<128> FakeModuleMapFile(Module->Directory->getName());
     llvm::sys::path::append(FakeModuleMapFile, "__inferred_module.map");
-    FrontendOpts.Inputs.emplace_back(FakeModuleMapFile, IK);
+    FrontendOpts.Inputs.emplace_back(FakeModuleMapFile, IK, +Module->IsSystem);
 
     llvm::raw_string_ostream OS(InferredModuleMapContent);
     Module->print(OS);
@@ -1144,11 +1149,6 @@ static bool compileModuleImpl(CompilerInstance &ImportingInstance,
     SourceMgr.overrideFileContents(ModuleMapFile, std::move(ModuleMapBuffer));
   }
 
-  // Construct a module-generating action. Passing through the module map is
-  // safe because the FileManager is shared between the compiler instances.
-  GenerateModuleFromModuleMapAction CreateModuleAction(
-      ModMap.getModuleMapFileForUniquing(Module), Module->IsSystem);
-
   ImportingInstance.getDiagnostics().Report(ImportLoc,
                                             diag::remark_module_build)
     << Module->Name << ModuleFileName;
@@ -1157,8 +1157,12 @@ static bool compileModuleImpl(CompilerInstance &ImportingInstance,
   // thread so that we get a stack large enough.
   const unsigned ThreadStackSize = 8 << 20;
   llvm::CrashRecoveryContext CRC;
-  CRC.RunSafelyOnThread([&]() { Instance.ExecuteAction(CreateModuleAction); },
-                        ThreadStackSize);
+  CRC.RunSafelyOnThread(
+      [&]() {
+        GenerateModuleFromModuleMapAction Action;
+        Instance.ExecuteAction(Action);
+      },
+      ThreadStackSize);
 
   ImportingInstance.getDiagnostics().Report(ImportLoc,
                                             diag::remark_module_build_done)
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 8cdb8298ee9e..d3ebf48315e2 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -81,7 +81,7 @@ using namespace llvm::opt;
 static unsigned getOptimizationLevel(ArgList &Args, InputKind IK,
                                      DiagnosticsEngine &Diags) {
   unsigned DefaultOpt = 0;
-  if (IK == IK_OpenCL && !Args.hasArg(OPT_cl_opt_disable))
+  if (IK.getLanguage() == InputKind::OpenCL && !Args.hasArg(OPT_cl_opt_disable))
     DefaultOpt = 2;
 
   if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
@@ -652,7 +652,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.EmitSummaryIndex = A && A->containsValue("thin");
   Opts.LTOUnit = Args.hasFlag(OPT_flto_unit, OPT_fno_lto_unit, false);
   if (Arg *A = Args.getLastArg(OPT_fthinlto_index_EQ)) {
-    if (IK != IK_LLVM_IR)
+    if (IK.getLanguage() != InputKind::LLVM_IR)
       Diags.Report(diag::err_drv_argument_only_allowed_with)
           << A->getAsString(Args) << "-x ir";
     Opts.ThinLTOIndexFile = Args.getLastArgValue(OPT_fthinlto_index_EQ);
@@ -1347,42 +1347,54 @@ static InputKind ParseFrontendArgs(FrontendOptions &Opts, ArgList &Args,
       << "ARC migration" << "ObjC migration";
   }
 
-  InputKind DashX = IK_None;
+  InputKind DashX(InputKind::Unknown);
   if (const Arg *A = Args.getLastArg(OPT_x)) {
-    DashX = llvm::StringSwitch<InputKind>(A->getValue())
-      .Case("c", IK_C)
-      .Case("cl", IK_OpenCL)
-      .Case("cuda", IK_CUDA)
-      .Case("c++", IK_CXX)
-      .Case("objective-c", IK_ObjC)
-      .Case("objective-c++", IK_ObjCXX)
-      .Case("cpp-output", IK_PreprocessedC)
-      .Case("assembler-with-cpp", IK_Asm)
-      .Case("c++-cpp-output", IK_PreprocessedCXX)
-      .Case("cuda-cpp-output", IK_PreprocessedCuda)
-      .Case("objective-c-cpp-output", IK_PreprocessedObjC)
-      .Case("objc-cpp-output", IK_PreprocessedObjC)
-      .Case("objective-c++-cpp-output", IK_PreprocessedObjCXX)
-      .Case("objc++-cpp-output", IK_PreprocessedObjCXX)
-      .Case("c-header", IK_C)
-      .Case("cl-header", IK_OpenCL)
-      .Case("objective-c-header", IK_ObjC)
-      .Case("c++-header", IK_CXX)
-      .Case("objective-c++-header", IK_ObjCXX)
-      .Cases("ast", "pcm", IK_AST)
-      .Case("ir", IK_LLVM_IR)
-      .Case("renderscript", IK_RenderScript)
-      .Default(IK_None);
-    if (DashX == IK_None)
+    StringRef XValue = A->getValue();
+
+    // Parse suffixes: '<lang>(-header|[-module-map][-cpp-output])'.
+    // FIXME: Supporting '<lang>-header-cpp-output' would be useful.
+    bool Preprocessed = XValue.consume_back("-cpp-output");
+    bool ModuleMap = XValue.consume_back("-module-map");
+    IsHeaderFile =
+        !Preprocessed && !ModuleMap && XValue.consume_back("-header");
+
+    // Principal languages.
+    DashX = llvm::StringSwitch<InputKind>(XValue)
+                .Case("c", InputKind::C)
+                .Case("cl", InputKind::OpenCL)
+                .Case("cuda", InputKind::CUDA)
+                .Case("c++", InputKind::CXX)
+                .Case("objective-c", InputKind::ObjC)
+                .Case("objective-c++", InputKind::ObjCXX)
+                .Case("renderscript", InputKind::RenderScript)
+                .Default(InputKind::Unknown);
+
+    // "objc[++]-cpp-output" is an acceptable synonym for
+    // "objective-c[++]-cpp-output".
+    if (DashX.isUnknown() && Preprocessed && !IsHeaderFile && !ModuleMap)
+      DashX = llvm::StringSwitch<InputKind>(XValue)
+                  .Case("objc", InputKind::ObjC)
+                  .Case("objc++", InputKind::ObjCXX)
+                  .Default(InputKind::Unknown);
+
+    // Some special cases cannot be combined with suffixes.
+    if (DashX.isUnknown() && !Preprocessed && !ModuleMap && !IsHeaderFile)
+      DashX = llvm::StringSwitch<InputKind>(XValue)
+                  .Case("cpp-output", InputKind(InputKind::C).getPreprocessed())
+                  .Case("assembler-with-cpp", InputKind::Asm)
+                  .Cases("ast", "pcm",
+                         InputKind(InputKind::Unknown, InputKind::Precompiled))
+                  .Case("ir", InputKind::LLVM_IR)
+                  .Default(InputKind::Unknown);
+
+    if (DashX.isUnknown())
       Diags.Report(diag::err_drv_invalid_value)
         << A->getAsString(Args) << A->getValue();
-    IsHeaderFile = llvm::StringSwitch<bool>(A->getValue())
-      .Case("c-header", true)
-      .Case("cl-header", true)
-      .Case("objective-c-header", true)
-      .Case("c++-header", true)
-      .Case("objective-c++-header", true)
-      .Default(false);
+
+    if (Preprocessed)
+      DashX = DashX.getPreprocessed();
+    if (ModuleMap)
+      DashX = DashX.withFormat(InputKind::ModuleMap);
   }
 
   // '-' is the default input if none is given.
@@ -1392,13 +1404,22 @@ static InputKind ParseFrontendArgs(FrontendOptions &Opts, ArgList &Args,
     Inputs.push_back("-");
   for (unsigned i = 0, e = Inputs.size(); i != e; ++i) {
     InputKind IK = DashX;
-    if (IK == IK_None) {
+    if (IK.isUnknown()) {
       IK = FrontendOptions::getInputKindForExtension(
         StringRef(Inputs[i]).rsplit('.').second);
+      // FIXME: Warn on this?
+      if (IK.isUnknown())
+        IK = InputKind::C;
       // FIXME: Remove this hack.
       if (i == 0)
         DashX = IK;
     }
+
+    // The -emit-module action implicitly takes a module map.
+    if (Opts.ProgramAction == frontend::GenerateModule &&
+        IK.getFormat() == InputKind::Source)
+      IK = IK.withFormat(InputKind::ModuleMap);
+
     Opts.Inputs.emplace_back(std::move(Inputs[i]), IK);
   }
 
@@ -1564,53 +1585,48 @@ void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
   // Set some properties which depend solely on the input kind; it would be nice
   // to move these to the language standard, and have the driver resolve the
   // input kind + language standard.
-  if (IK == IK_Asm) {
+  //
+  // FIXME: Perhaps a better model would be for a single source file to have
+  // multiple language standards (C / C++ std, ObjC std, OpenCL std, OpenMP std)
+  // simultaneously active?
+  if (IK.getLanguage() == InputKind::Asm) {
     Opts.AsmPreprocessor = 1;
-  } else if (IK == IK_ObjC ||
-             IK == IK_ObjCXX ||
-             IK == IK_PreprocessedObjC ||
-             IK == IK_PreprocessedObjCXX) {
+  } else if (IK.isObjectiveC()) {
     Opts.ObjC1 = Opts.ObjC2 = 1;
   }
 
   if (LangStd == LangStandard::lang_unspecified) {
     // Based on the base language, pick one.
-    switch (IK) {
-    case IK_None:
-    case IK_AST:
-    case IK_LLVM_IR:
+    switch (IK.getLanguage()) {
+    case InputKind::Unknown:
+    case InputKind::LLVM_IR:
       llvm_unreachable("Invalid input kind!");
-    case IK_OpenCL:
-      LangStd = LangStandard::lang_opencl;
+    case InputKind::OpenCL:
+      LangStd = LangStandard::lang_opencl10;
       break;
-    case IK_CUDA:
-    case IK_PreprocessedCuda:
+    case InputKind::CUDA:
       LangStd = LangStandard::lang_cuda;
       break;
-    case IK_Asm:
-    case IK_C:
-    case IK_PreprocessedC:
+    case InputKind::Asm:
+    case InputKind::C:
       // The PS4 uses C99 as the default C standard.
       if (T.isPS4())
         LangStd = LangStandard::lang_gnu99;
       else
         LangStd = LangStandard::lang_gnu11;
       break;
-    case IK_ObjC:
-    case IK_PreprocessedObjC:
+    case InputKind::ObjC:
       LangStd = LangStandard::lang_gnu11;
       break;
-    case IK_CXX:
-    case IK_PreprocessedCXX:
-    case IK_ObjCXX:
-    case IK_PreprocessedObjCXX:
+    case InputKind::CXX:
+    case InputKind::ObjCXX:
       // The PS4 uses C++11 as the default C++ standard.
       if (T.isPS4())
         LangStd = LangStandard::lang_gnucxx11;
       else
         LangStd = LangStandard::lang_gnucxx98;
       break;
-    case IK_RenderScript:
+    case InputKind::RenderScript:
       LangStd = LangStandard::lang_c99;
       break;
     }
@@ -1626,13 +1642,13 @@ void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
   Opts.CPlusPlus1z = Std.isCPlusPlus1z();
   Opts.Digraphs = Std.hasDigraphs();
   Opts.GNUMode = Std.isGNUMode();
-  Opts.GNUInline = Std.isC89();
+  Opts.GNUInline = !Opts.C99 && !Opts.CPlusPlus;
   Opts.HexFloats = Std.hasHexFloats();
   Opts.ImplicitInt = Std.hasImplicitInt();
 
   // Set OpenCL Version.
-  Opts.OpenCL = Std.isOpenCL() || IK == IK_OpenCL;
-  if (LangStd == LangStandard::lang_opencl)
+  Opts.OpenCL = Std.isOpenCL();
+  if (LangStd == LangStandard::lang_opencl10)
     Opts.OpenCLVersion = 100;
   else if (LangStd == LangStandard::lang_opencl11)
     Opts.OpenCLVersion = 110;
@@ -1655,13 +1671,12 @@ void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
     }
   }
 
-  Opts.CUDA = IK == IK_CUDA || IK == IK_PreprocessedCuda ||
-              LangStd == LangStandard::lang_cuda;
+  Opts.CUDA = IK.getLanguage() == InputKind::CUDA;
   if (Opts.CUDA)
     // Set default FP_CONTRACT to FAST.
     Opts.setDefaultFPContractMode(LangOptions::FPC_Fast);
 
-  Opts.RenderScript = IK == IK_RenderScript;
+  Opts.RenderScript = IK.getLanguage() == InputKind::RenderScript;
   if (Opts.RenderScript) {
     Opts.NativeHalfType = 1;
     Opts.NativeHalfArgsAndReturns = 1;
@@ -1705,58 +1720,65 @@ static Visibility parseVisibility(Arg *arg, ArgList &args,
 /// Check if input file kind and language standard are compatible.
 static bool IsInputCompatibleWithStandard(InputKind IK,
                                           const LangStandard &S) {
-  switch (IK) {
-  case IK_C:
-  case IK_ObjC:
-  case IK_PreprocessedC:
-  case IK_PreprocessedObjC:
-    if (S.isC89() || S.isC99())
-      return true;
-    break;
-  case IK_CXX:
-  case IK_ObjCXX:
-  case IK_PreprocessedCXX:
-  case IK_PreprocessedObjCXX:
-    if (S.isCPlusPlus())
-      return true;
-    break;
-  case IK_OpenCL:
-    if (S.isOpenCL())
-      return true;
-    break;
-  case IK_CUDA:
-  case IK_PreprocessedCuda:
-    if (S.isCPlusPlus())
-      return true;
-    break;
-  default:
-    // For other inputs, accept (and ignore) all -std= values.
+  switch (IK.getLanguage()) {
+  case InputKind::Unknown:
+  case InputKind::LLVM_IR:
+    llvm_unreachable("should not parse language flags for this input");
+
+  case InputKind::C:
+  case InputKind::ObjC:
+  case InputKind::RenderScript:
+    return S.getLanguage() == InputKind::C;
+
+  case InputKind::OpenCL:
+    return S.getLanguage() == InputKind::OpenCL;
+
+  case InputKind::CXX:
+  case InputKind::ObjCXX:
+    return S.getLanguage() == InputKind::CXX;
+
+  case InputKind::CUDA:
+    // FIXME: What -std= values should be permitted for CUDA compilations?
+    return S.getLanguage() == InputKind::CUDA ||
+           S.getLanguage() == InputKind::CXX;
+
+  case InputKind::Asm:
+    // Accept (and ignore) all -std= values.
+    // FIXME: The -std= value is not ignored; it affects the tokenization
+    // and preprocessing rules if we're preprocessing this asm input.
     return true;
   }
-  return false;
+
+  llvm_unreachable("unexpected input language");
 }
 
 /// Get language name for given input kind.
 static const StringRef GetInputKindName(InputKind IK) {
-  switch (IK) {
-  case IK_C:
-  case IK_ObjC:
-  case IK_PreprocessedC:
-  case IK_PreprocessedObjC:
-    return "C/ObjC";
-  case IK_CXX:
-  case IK_ObjCXX:
-  case IK_PreprocessedCXX:
-  case IK_PreprocessedObjCXX:
-    return "C++/ObjC++";
-  case IK_OpenCL:
+  switch (IK.getLanguage()) {
+  case InputKind::C:
+    return "C";
+  case InputKind::ObjC:
+    return "Objective-C";
+  case InputKind::CXX:
+    return "C++";
+  case InputKind::ObjCXX:
+    return "Objective-C++";
+  case InputKind::OpenCL:
     return "OpenCL";
-  case IK_CUDA:
-  case IK_PreprocessedCuda:
+  case InputKind::CUDA:
     return "CUDA";
-  default:
-    llvm_unreachable("Cannot decide on name for InputKind!");
+  case InputKind::RenderScript:
+    return "RenderScript";
+
+  case InputKind::Asm:
+    return "Asm";
+  case InputKind::LLVM_IR:
+    return "LLVM IR";
+
+  case InputKind::Unknown:
+    break;
   }
+  llvm_unreachable("unknown input language");
 }
 
 static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
@@ -1767,7 +1789,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   LangStandard::Kind LangStd = LangStandard::lang_unspecified;
   if (const Arg *A = Args.getLastArg(OPT_std_EQ)) {
     LangStd = llvm::StringSwitch<LangStandard::Kind>(A->getValue())
-#define LANGSTANDARD(id, name, desc, features) \
+#define LANGSTANDARD(id, name, lang, desc, features) \
       .Case(name, LangStandard::lang_##id)
 #define LANGSTANDARD_ALIAS(id, alias) \
       .Case(alias, LangStandard::lang_##id)
@@ -1783,8 +1805,20 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
         const LangStandard &Std = LangStandard::getLangStandardForKind(
           static_cast<LangStandard::Kind>(KindValue));
         if (IsInputCompatibleWithStandard(IK, Std)) {
-          Diags.Report(diag::note_drv_use_standard)
-            << Std.getName() << Std.getDescription();
+          auto Diag = Diags.Report(diag::note_drv_use_standard);
+          Diag << Std.getName() << Std.getDescription();
+          unsigned NumAliases = 0;
+#define LANGSTANDARD(id, name, lang, desc, features)
+#define LANGSTANDARD_ALIAS(id, alias) \
+          if (KindValue == LangStandard::lang_##id) ++NumAliases;
+#define LANGSTANDARD_ALIAS_DEPR(id, alias)
+#include "clang/Frontend/LangStandards.def"
+          Diag << NumAliases;
+#define LANGSTANDARD(id, name, lang, desc, features)
+#define LANGSTANDARD_ALIAS(id, alias) \
+          if (KindValue == LangStandard::lang_##id) Diag << alias;
+#define LANGSTANDARD_ALIAS_DEPR(id, alias)
+#include "clang/Frontend/LangStandards.def"
         }
       }
     } else {
@@ -1803,7 +1837,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   if (const Arg *A = Args.getLastArg(OPT_cl_std_EQ)) {
     LangStandard::Kind OpenCLLangStd
       = llvm::StringSwitch<LangStandard::Kind>(A->getValue())
-        .Cases("cl", "CL", LangStandard::lang_opencl)
+        .Cases("cl", "CL", LangStandard::lang_opencl10)
         .Cases("cl1.1", "CL1.1", LangStandard::lang_opencl11)
         .Cases("cl1.2", "CL1.2", LangStandard::lang_opencl12)
         .Cases("cl2.0", "CL2.0", LangStandard::lang_opencl20)
@@ -2533,7 +2567,8 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
                               Res.getTargetOpts());
   ParseHeaderSearchArgs(Res.getHeaderSearchOpts(), Args,
                         Res.getFileSystemOpts().WorkingDir);
-  if (DashX == IK_AST || DashX == IK_LLVM_IR) {
+  if (DashX.getFormat() == InputKind::Precompiled ||
+      DashX.getLanguage() == InputKind::LLVM_IR) {
     // ObjCAAutoRefCount and Sanitize LangOpts are used to setup the
     // PassManager in BackendUtil.cpp. They need to be initializd no matter
     // what the input type is.
@@ -2547,8 +2582,9 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
                         Diags, LangOpts.Sanitize);
   } else {
     // Other LangOpts are only initialzed when the input is not AST or LLVM IR.
+    // FIXME: Should we really be calling this for an InputKind::Asm input?
     ParseLangArgs(LangOpts, Args, DashX, Res.getTargetOpts(),
-      Res.getPreprocessorOpts(), Diags);
+                  Res.getPreprocessorOpts(), Diags);
     if (Res.getFrontendOpts().ProgramAction == frontend::RewriteObjC)
       LangOpts.ObjCExceptions = 1;
   }
diff --git a/lib/Frontend/FrontendAction.cpp b/lib/Frontend/FrontendAction.cpp
index 0dd07d9f817b..d26b6937b851 100644
--- a/lib/Frontend/FrontendAction.cpp
+++ b/lib/Frontend/FrontendAction.cpp
@@ -224,6 +224,231 @@ static bool ReadOriginalFileName(CompilerInstance &CI, std::string &InputFile)
   return true;
 }
 
+static SmallVectorImpl<char> &
+operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
+  Includes.append(RHS.begin(), RHS.end());
+  return Includes;
+}
+
+static void addHeaderInclude(StringRef HeaderName,
+                             SmallVectorImpl<char> &Includes,
+                             const LangOptions &LangOpts,
+                             bool IsExternC) {
+  if (IsExternC && LangOpts.CPlusPlus)
+    Includes += "extern \"C\" {\n";
+  if (LangOpts.ObjC1)
+    Includes += "#import \"";
+  else
+    Includes += "#include \"";
+
+  Includes += HeaderName;
+
+  Includes += "\"\n";
+  if (IsExternC && LangOpts.CPlusPlus)
+    Includes += "}\n";
+}
+
+/// \brief Collect the set of header includes needed to construct the given 
+/// module and update the TopHeaders file set of the module.
+///
+/// \param Module The module we're collecting includes from.
+///
+/// \param Includes Will be augmented with the set of \#includes or \#imports
+/// needed to load all of the named headers.
+static std::error_code
+collectModuleHeaderIncludes(const LangOptions &LangOpts, FileManager &FileMgr,
+                            ModuleMap &ModMap, clang::Module *Module,
+                            SmallVectorImpl<char> &Includes) {
+  // Don't collect any headers for unavailable modules.
+  if (!Module->isAvailable())
+    return std::error_code();
+
+  // Add includes for each of these headers.
+  for (auto HK : {Module::HK_Normal, Module::HK_Private}) {
+    for (Module::Header &H : Module->Headers[HK]) {
+      Module->addTopHeader(H.Entry);
+      // Use the path as specified in the module map file. We'll look for this
+      // file relative to the module build directory (the directory containing
+      // the module map file) so this will find the same file that we found
+      // while parsing the module map.
+      addHeaderInclude(H.NameAsWritten, Includes, LangOpts, Module->IsExternC);
+    }
+  }
+  // Note that Module->PrivateHeaders will not be a TopHeader.
+
+  if (Module::Header UmbrellaHeader = Module->getUmbrellaHeader()) {
+    Module->addTopHeader(UmbrellaHeader.Entry);
+    if (Module->Parent)
+      // Include the umbrella header for submodules.
+      addHeaderInclude(UmbrellaHeader.NameAsWritten, Includes, LangOpts,
+                       Module->IsExternC);
+  } else if (Module::DirectoryName UmbrellaDir = Module->getUmbrellaDir()) {
+    // Add all of the headers we find in this subdirectory.
+    std::error_code EC;
+    SmallString<128> DirNative;
+    llvm::sys::path::native(UmbrellaDir.Entry->getName(), DirNative);
+
+    vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+    for (vfs::recursive_directory_iterator Dir(FS, DirNative, EC), End;
+         Dir != End && !EC; Dir.increment(EC)) {
+      // Check whether this entry has an extension typically associated with 
+      // headers.
+      if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->getName()))
+          .Cases(".h", ".H", ".hh", ".hpp", true)
+          .Default(false))
+        continue;
+
+      const FileEntry *Header = FileMgr.getFile(Dir->getName());
+      // FIXME: This shouldn't happen unless there is a file system race. Is
+      // that worth diagnosing?
+      if (!Header)
+        continue;
+
+      // If this header is marked 'unavailable' in this module, don't include 
+      // it.
+      if (ModMap.isHeaderUnavailableInModule(Header, Module))
+        continue;
+
+      // Compute the relative path from the directory to this file.
+      SmallVector<StringRef, 16> Components;
+      auto PathIt = llvm::sys::path::rbegin(Dir->getName());
+      for (int I = 0; I != Dir.level() + 1; ++I, ++PathIt)
+        Components.push_back(*PathIt);
+      SmallString<128> RelativeHeader(UmbrellaDir.NameAsWritten);
+      for (auto It = Components.rbegin(), End = Components.rend(); It != End;
+           ++It)
+        llvm::sys::path::append(RelativeHeader, *It);
+
+      // Include this header as part of the umbrella directory.
+      Module->addTopHeader(Header);
+      addHeaderInclude(RelativeHeader, Includes, LangOpts, Module->IsExternC);
+    }
+
+    if (EC)
+      return EC;
+  }
+
+  // Recurse into submodules.
+  for (clang::Module::submodule_iterator Sub = Module->submodule_begin(),
+                                      SubEnd = Module->submodule_end();
+       Sub != SubEnd; ++Sub)
+    if (std::error_code Err = collectModuleHeaderIncludes(
+            LangOpts, FileMgr, ModMap, *Sub, Includes))
+      return Err;
+
+  return std::error_code();
+}
+
+/// Parse a module map and compute the corresponding real input buffer that
+/// should be used to build the module described by that module map and the
+/// current module name.
+static std::unique_ptr<llvm::MemoryBuffer>
+getInputBufferForModuleMap(CompilerInstance &CI, StringRef Filename,
+                           bool IsSystem) {
+  // Find the module map file.
+  const FileEntry *ModuleMap =
+      CI.getFileManager().getFile(Filename, /*openFile*/true);
+  if (!ModuleMap)  {
+    CI.getDiagnostics().Report(diag::err_module_map_not_found)
+      << Filename;
+    return nullptr;
+  }
+
+  // Find the module map file from which it was generated, if different.
+  const FileEntry *OriginalModuleMap = ModuleMap;
+  StringRef OriginalModuleMapName = CI.getFrontendOpts().OriginalModuleMap;
+  if (!OriginalModuleMapName.empty()) {
+    OriginalModuleMap = CI.getFileManager().getFile(OriginalModuleMapName,
+                                                    /*openFile*/ true);
+    if (!OriginalModuleMap) {
+      CI.getDiagnostics().Report(diag::err_module_map_not_found)
+        << OriginalModuleMapName;
+      return nullptr;
+    }
+  }
+  
+  // Parse the module map file.
+  HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
+  if (HS.loadModuleMapFile(ModuleMap, IsSystem))
+    return nullptr;
+  
+  if (CI.getLangOpts().CurrentModule.empty()) {
+    CI.getDiagnostics().Report(diag::err_missing_module_name);
+    
+    // FIXME: Eventually, we could consider asking whether there was just
+    // a single module described in the module map, and use that as a 
+    // default. Then it would be fairly trivial to just "compile" a module
+    // map with a single module (the common case).
+    return nullptr;
+  }
+
+  // If we're being run from the command-line, the module build stack will not
+  // have been filled in yet, so complete it now in order to allow us to detect
+  // module cycles.
+  SourceManager &SourceMgr = CI.getSourceManager();
+  if (SourceMgr.getModuleBuildStack().empty())
+    SourceMgr.pushModuleBuildStack(CI.getLangOpts().CurrentModule,
+                                   FullSourceLoc(SourceLocation(), SourceMgr));
+
+  // Dig out the module definition.
+  Module *M = HS.lookupModule(CI.getLangOpts().CurrentModule,
+                              /*AllowSearch=*/false);
+  if (!M) {
+    CI.getDiagnostics().Report(diag::err_missing_module)
+      << CI.getLangOpts().CurrentModule << Filename;
+    
+    return nullptr;
+  }
+
+  // Check whether we can build this module at all.
+  clang::Module::Requirement Requirement;
+  clang::Module::UnresolvedHeaderDirective MissingHeader;
+  if (!M->isAvailable(CI.getLangOpts(), CI.getTarget(), Requirement,
+                      MissingHeader)) {
+    if (MissingHeader.FileNameLoc.isValid()) {
+      CI.getDiagnostics().Report(MissingHeader.FileNameLoc,
+                                 diag::err_module_header_missing)
+        << MissingHeader.IsUmbrella << MissingHeader.FileName;
+    } else {
+      CI.getDiagnostics().Report(diag::err_module_unavailable)
+        << M->getFullModuleName() << Requirement.second << Requirement.first;
+    }
+
+    return nullptr;
+  }
+
+  if (OriginalModuleMap != ModuleMap) {
+    M->IsInferred = true;
+    HS.getModuleMap().setInferredModuleAllowedBy(M, OriginalModuleMap);
+  }
+
+  FileManager &FileMgr = CI.getFileManager();
+
+  // Collect the set of #includes we need to build the module.
+  SmallString<256> HeaderContents;
+  std::error_code Err = std::error_code();
+  if (Module::Header UmbrellaHeader = M->getUmbrellaHeader())
+    addHeaderInclude(UmbrellaHeader.NameAsWritten, HeaderContents,
+                     CI.getLangOpts(), M->IsExternC);
+  Err = collectModuleHeaderIncludes(
+      CI.getLangOpts(), FileMgr,
+      CI.getPreprocessor().getHeaderSearchInfo().getModuleMap(), M,
+      HeaderContents);
+
+  if (Err) {
+    CI.getDiagnostics().Report(diag::err_module_cannot_create_includes)
+      << M->getFullModuleName() << Err.message();
+    return nullptr;
+  }
+
+  // Inform the preprocessor that includes from within the input buffer should
+  // be resolved relative to the build directory of the module map file.
+  CI.getPreprocessor().setMainFileDir(M->Directory);
+
+  return llvm::MemoryBuffer::getMemBufferCopy(
+      HeaderContents, Module::getModuleInputBufferName());
+}
+
 bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
                                      const FrontendInputFile &Input) {
   assert(!Instance && "Already processing a source file!");
@@ -232,13 +457,15 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
   setCompilerInstance(&CI);
 
   StringRef InputFile = Input.getFile();
+  FrontendInputFile FileToProcess = Input;
   bool HasBegunSourceFile = false;
   if (!BeginInvocation(CI))
     goto failure;
 
   // AST files follow a very different path, since they share objects via the
   // AST unit.
-  if (Input.getKind() == IK_AST) {
+  if (Input.getKind().getFormat() == InputKind::Precompiled) {
+    // FIXME: We should not be asserting on bad command-line arguments.
     assert(!usesPreprocessorOnly() &&
            "Attempt to pass AST file to preprocessor only action!");
     assert(hasASTFileSupport() &&
@@ -296,8 +523,19 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
   if (!CI.hasSourceManager())
     CI.createSourceManager(CI.getFileManager());
 
+  // Set up embedding for any specified files. Do this before we load any
+  // source files, including the primary module map for the compilation.
+  for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
+    if (const auto *FE = CI.getFileManager().getFile(F, /*openFile*/true))
+      CI.getSourceManager().setFileIsTransient(FE);
+    else
+      CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
+  }
+  if (CI.getFrontendOpts().ModulesEmbedAllFiles)
+    CI.getSourceManager().setAllFilesAreTransient(true);
+
   // IR files bypass the rest of initialization.
-  if (Input.getKind() == IK_LLVM_IR) {
+  if (Input.getKind().getLanguage() == InputKind::LLVM_IR) {
     assert(hasIRSupport() &&
            "This action does not have IR file support!");
 
@@ -359,13 +597,34 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
                                            &CI.getPreprocessor());
   HasBegunSourceFile = true;
 
+  // For module map files, we first parse the module map and synthesize a
+  // "<module-includes>" buffer before more conventional processing.
+  if (Input.getKind().getFormat() == InputKind::ModuleMap) {
+    CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleMap);
+
+    auto Buffer = getInputBufferForModuleMap(CI, InputFile, Input.isSystem());
+    if (!Buffer)
+      goto failure;
+
+    Module *CurrentModule =
+        CI.getPreprocessor().getHeaderSearchInfo().lookupModule(
+            CI.getLangOpts().CurrentModule,
+            /*AllowSearch=*/false);
+    assert(CurrentModule && "no module info for current module");
+
+    // The input that we end up processing is the generated buffer, not the
+    // module map file itself.
+    FileToProcess = FrontendInputFile(
+        Buffer.release(), Input.getKind().withFormat(InputKind::Source),
+        CurrentModule->IsSystem);
+  }
+
   // Initialize the action.
   if (!BeginSourceFileAction(CI, InputFile))
     goto failure;
 
-  // Initialize the main file entry. It is important that this occurs after
-  // BeginSourceFileAction, which may change CurrentInput during module builds.
-  if (!CI.InitializeSourceManager(CurrentInput))
+  // Initialize the main file entry.
+  if (!CI.InitializeSourceManager(FileToProcess))
     goto failure;
 
   // Create the AST context and consumer unless this is a preprocessor only
@@ -497,6 +756,7 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
   if (HasBegunSourceFile)
     CI.getDiagnosticClient().EndSourceFile();
   CI.clearOutputFiles(/*EraseFiles=*/true);
+  CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
   setCurrentInput(FrontendInputFile());
   setCompilerInstance(nullptr);
   return false;
@@ -579,6 +839,7 @@ void FrontendAction::EndSourceFile() {
 
   setCompilerInstance(nullptr);
   setCurrentInput(FrontendInputFile());
+  CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
 }
 
 bool FrontendAction::shouldEraseOutputFiles() {
diff --git a/lib/Frontend/FrontendActions.cpp b/lib/Frontend/FrontendActions.cpp
index e818038b1354..dd7c12f60f0e 100644
--- a/lib/Frontend/FrontendActions.cpp
+++ b/lib/Frontend/FrontendActions.cpp
@@ -164,242 +164,9 @@ GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
 }
 
-bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI, 
-                                                 StringRef Filename) {
-  // Set up embedding for any specified files. Do this before we load any
-  // source files, including the primary module map for the compilation.
-  for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
-    if (const auto *FE = CI.getFileManager().getFile(F, /*openFile*/true))
-      CI.getSourceManager().setFileIsTransient(FE);
-    else
-      CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
-  }
-  if (CI.getFrontendOpts().ModulesEmbedAllFiles)
-    CI.getSourceManager().setAllFilesAreTransient(true);
-
-  return true;
-}
-
-
-static SmallVectorImpl<char> &
-operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
-  Includes.append(RHS.begin(), RHS.end());
-  return Includes;
-}
-
-static void addHeaderInclude(StringRef HeaderName,
-                             SmallVectorImpl<char> &Includes,
-                             const LangOptions &LangOpts,
-                             bool IsExternC) {
-  if (IsExternC && LangOpts.CPlusPlus)
-    Includes += "extern \"C\" {\n";
-  if (LangOpts.ObjC1)
-    Includes += "#import \"";
-  else
-    Includes += "#include \"";
-
-  Includes += HeaderName;
-
-  Includes += "\"\n";
-  if (IsExternC && LangOpts.CPlusPlus)
-    Includes += "}\n";
-}
-
-/// \brief Collect the set of header includes needed to construct the given 
-/// module and update the TopHeaders file set of the module.
-///
-/// \param Module The module we're collecting includes from.
-///
-/// \param Includes Will be augmented with the set of \#includes or \#imports
-/// needed to load all of the named headers.
-static std::error_code
-collectModuleHeaderIncludes(const LangOptions &LangOpts, FileManager &FileMgr,
-                            ModuleMap &ModMap, clang::Module *Module,
-                            SmallVectorImpl<char> &Includes) {
-  // Don't collect any headers for unavailable modules.
-  if (!Module->isAvailable())
-    return std::error_code();
-
-  // Add includes for each of these headers.
-  for (auto HK : {Module::HK_Normal, Module::HK_Private}) {
-    for (Module::Header &H : Module->Headers[HK]) {
-      Module->addTopHeader(H.Entry);
-      // Use the path as specified in the module map file. We'll look for this
-      // file relative to the module build directory (the directory containing
-      // the module map file) so this will find the same file that we found
-      // while parsing the module map.
-      addHeaderInclude(H.NameAsWritten, Includes, LangOpts, Module->IsExternC);
-    }
-  }
-  // Note that Module->PrivateHeaders will not be a TopHeader.
-
-  if (Module::Header UmbrellaHeader = Module->getUmbrellaHeader()) {
-    Module->addTopHeader(UmbrellaHeader.Entry);
-    if (Module->Parent)
-      // Include the umbrella header for submodules.
-      addHeaderInclude(UmbrellaHeader.NameAsWritten, Includes, LangOpts,
-                       Module->IsExternC);
-  } else if (Module::DirectoryName UmbrellaDir = Module->getUmbrellaDir()) {
-    // Add all of the headers we find in this subdirectory.
-    std::error_code EC;
-    SmallString<128> DirNative;
-    llvm::sys::path::native(UmbrellaDir.Entry->getName(), DirNative);
-
-    vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
-    for (vfs::recursive_directory_iterator Dir(FS, DirNative, EC), End;
-         Dir != End && !EC; Dir.increment(EC)) {
-      // Check whether this entry has an extension typically associated with 
-      // headers.
-      if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->getName()))
-          .Cases(".h", ".H", ".hh", ".hpp", true)
-          .Default(false))
-        continue;
-
-      const FileEntry *Header = FileMgr.getFile(Dir->getName());
-      // FIXME: This shouldn't happen unless there is a file system race. Is
-      // that worth diagnosing?
-      if (!Header)
-        continue;
-
-      // If this header is marked 'unavailable' in this module, don't include 
-      // it.
-      if (ModMap.isHeaderUnavailableInModule(Header, Module))
-        continue;
-
-      // Compute the relative path from the directory to this file.
-      SmallVector<StringRef, 16> Components;
-      auto PathIt = llvm::sys::path::rbegin(Dir->getName());
-      for (int I = 0; I != Dir.level() + 1; ++I, ++PathIt)
-        Components.push_back(*PathIt);
-      SmallString<128> RelativeHeader(UmbrellaDir.NameAsWritten);
-      for (auto It = Components.rbegin(), End = Components.rend(); It != End;
-           ++It)
-        llvm::sys::path::append(RelativeHeader, *It);
-
-      // Include this header as part of the umbrella directory.
-      Module->addTopHeader(Header);
-      addHeaderInclude(RelativeHeader, Includes, LangOpts, Module->IsExternC);
-    }
-
-    if (EC)
-      return EC;
-  }
-
-  // Recurse into submodules.
-  for (clang::Module::submodule_iterator Sub = Module->submodule_begin(),
-                                      SubEnd = Module->submodule_end();
-       Sub != SubEnd; ++Sub)
-    if (std::error_code Err = collectModuleHeaderIncludes(
-            LangOpts, FileMgr, ModMap, *Sub, Includes))
-      return Err;
-
-  return std::error_code();
-}
-
 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
     CompilerInstance &CI, StringRef Filename) {
-  CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleMap);
-
-  if (!GenerateModuleAction::BeginSourceFileAction(CI, Filename))
-    return false;
-
-  // Find the module map file.
-  const FileEntry *ModuleMap =
-      CI.getFileManager().getFile(Filename, /*openFile*/true);
-  if (!ModuleMap)  {
-    CI.getDiagnostics().Report(diag::err_module_map_not_found)
-      << Filename;
-    return false;
-  }
-  
-  // Parse the module map file.
-  HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
-  if (HS.loadModuleMapFile(ModuleMap, IsSystem))
-    return false;
-  
-  if (CI.getLangOpts().CurrentModule.empty()) {
-    CI.getDiagnostics().Report(diag::err_missing_module_name);
-    
-    // FIXME: Eventually, we could consider asking whether there was just
-    // a single module described in the module map, and use that as a 
-    // default. Then it would be fairly trivial to just "compile" a module
-    // map with a single module (the common case).
-    return false;
-  }
-
-  // If we're being run from the command-line, the module build stack will not
-  // have been filled in yet, so complete it now in order to allow us to detect
-  // module cycles.
-  SourceManager &SourceMgr = CI.getSourceManager();
-  if (SourceMgr.getModuleBuildStack().empty())
-    SourceMgr.pushModuleBuildStack(CI.getLangOpts().CurrentModule,
-                                   FullSourceLoc(SourceLocation(), SourceMgr));
-
-  // Dig out the module definition.
-  Module = HS.lookupModule(CI.getLangOpts().CurrentModule, 
-                           /*AllowSearch=*/false);
-  if (!Module) {
-    CI.getDiagnostics().Report(diag::err_missing_module)
-      << CI.getLangOpts().CurrentModule << Filename;
-    
-    return false;
-  }
-
-  // Check whether we can build this module at all.
-  clang::Module::Requirement Requirement;
-  clang::Module::UnresolvedHeaderDirective MissingHeader;
-  if (!Module->isAvailable(CI.getLangOpts(), CI.getTarget(), Requirement,
-                           MissingHeader)) {
-    if (MissingHeader.FileNameLoc.isValid()) {
-      CI.getDiagnostics().Report(MissingHeader.FileNameLoc,
-                                 diag::err_module_header_missing)
-        << MissingHeader.IsUmbrella << MissingHeader.FileName;
-    } else {
-      CI.getDiagnostics().Report(diag::err_module_unavailable)
-        << Module->getFullModuleName()
-        << Requirement.second << Requirement.first;
-    }
-
-    return false;
-  }
-
-  if (ModuleMapForUniquing && ModuleMapForUniquing != ModuleMap) {
-    Module->IsInferred = true;
-    HS.getModuleMap().setInferredModuleAllowedBy(Module, ModuleMapForUniquing);
-  } else {
-    ModuleMapForUniquing = ModuleMap;
-  }
-
-  FileManager &FileMgr = CI.getFileManager();
-
-  // Collect the set of #includes we need to build the module.
-  SmallString<256> HeaderContents;
-  std::error_code Err = std::error_code();
-  if (Module::Header UmbrellaHeader = Module->getUmbrellaHeader())
-    addHeaderInclude(UmbrellaHeader.NameAsWritten, HeaderContents,
-                     CI.getLangOpts(), Module->IsExternC);
-  Err = collectModuleHeaderIncludes(
-        CI.getLangOpts(), FileMgr,
-        CI.getPreprocessor().getHeaderSearchInfo().getModuleMap(), Module,
-        HeaderContents);
-
-  if (Err) {
-    CI.getDiagnostics().Report(diag::err_module_cannot_create_includes)
-      << Module->getFullModuleName() << Err.message();
-    return false;
-  }
-
-  // Inform the preprocessor that includes from within the input buffer should
-  // be resolved relative to the build directory of the module map file.
-  CI.getPreprocessor().setMainFileDir(Module->Directory);
-
-  std::unique_ptr<llvm::MemoryBuffer> InputBuffer =
-      llvm::MemoryBuffer::getMemBufferCopy(HeaderContents,
-                                           Module::getModuleInputBufferName());
-  // Ownership of InputBuffer will be transferred to the SourceManager.
-  setCurrentInput(FrontendInputFile(InputBuffer.release(), getCurrentFileKind(),
-                                    Module->IsSystem));
-  return true;
+  return GenerateModuleAction::BeginSourceFileAction(CI, Filename);
 }
 
 std::unique_ptr<raw_pwrite_stream>
@@ -408,10 +175,13 @@ GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
   // If no output file was provided, figure out where this module would go
   // in the module cache.
   if (CI.getFrontendOpts().OutputFile.empty()) {
+    StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
+    if (ModuleMapFile.empty())
+      ModuleMapFile = InFile;
+
     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
     CI.getFrontendOpts().OutputFile =
-        HS.getModuleFileName(CI.getLangOpts().CurrentModule,
-                             ModuleMapForUniquing->getName(),
+        HS.getModuleFileName(CI.getLangOpts().CurrentModule, ModuleMapFile,
                              /*UsePrebuiltPath=*/false);
   }
 
@@ -777,29 +547,27 @@ void PrintPreprocessedAction::ExecuteAction() {
 }
 
 void PrintPreambleAction::ExecuteAction() {
-  switch (getCurrentFileKind()) {
-  case IK_C:
-  case IK_CXX:
-  case IK_ObjC:
-  case IK_ObjCXX:
-  case IK_OpenCL:
-  case IK_CUDA:
+  switch (getCurrentFileKind().getLanguage()) {
+  case InputKind::C:
+  case InputKind::CXX:
+  case InputKind::ObjC:
+  case InputKind::ObjCXX:
+  case InputKind::OpenCL:
+  case InputKind::CUDA:
     break;
       
-  case IK_None:
-  case IK_Asm:
-  case IK_PreprocessedC:
-  case IK_PreprocessedCuda:
-  case IK_PreprocessedCXX:
-  case IK_PreprocessedObjC:
-  case IK_PreprocessedObjCXX:
-  case IK_AST:
-  case IK_LLVM_IR:
-  case IK_RenderScript:
+  case InputKind::Unknown:
+  case InputKind::Asm:
+  case InputKind::LLVM_IR:
+  case InputKind::RenderScript:
     // We can't do anything with these.
     return;
   }
 
+  // We don't expect to find any #include directives in a preprocessed input.
+  if (getCurrentFileKind().isPreprocessed())
+    return;
+
   CompilerInstance &CI = getCompilerInstance();
   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
   if (Buffer) {
diff --git a/lib/Frontend/FrontendOptions.cpp b/lib/Frontend/FrontendOptions.cpp
index 6a82084aff1b..dca434588fb1 100644
--- a/lib/Frontend/FrontendOptions.cpp
+++ b/lib/Frontend/FrontendOptions.cpp
@@ -13,22 +13,22 @@ using namespace clang;
 
 InputKind FrontendOptions::getInputKindForExtension(StringRef Extension) {
   return llvm::StringSwitch<InputKind>(Extension)
-    .Cases("ast", "pcm", IK_AST)
-    .Case("c", IK_C)
-    .Cases("S", "s", IK_Asm)
-    .Case("i", IK_PreprocessedC)
-    .Case("ii", IK_PreprocessedCXX)
-    .Case("cui", IK_PreprocessedCuda)
-    .Case("m", IK_ObjC)
-    .Case("mi", IK_PreprocessedObjC)
-    .Cases("mm", "M", IK_ObjCXX)
-    .Case("mii", IK_PreprocessedObjCXX)
-    .Cases("C", "cc", "cp", IK_CXX)
-    .Cases("cpp", "CPP", "c++", "cxx", "hpp", IK_CXX)
-    .Case("cppm", IK_CXX)
-    .Case("iim", IK_PreprocessedCXX)
-    .Case("cl", IK_OpenCL)
-    .Case("cu", IK_CUDA)
-    .Cases("ll", "bc", IK_LLVM_IR)
-    .Default(IK_C);
+    .Cases("ast", "pcm", InputKind(InputKind::Unknown, InputKind::Precompiled))
+    .Case("c", InputKind::C)
+    .Cases("S", "s", InputKind::Asm)
+    .Case("i", InputKind(InputKind::C).getPreprocessed())
+    .Case("ii", InputKind(InputKind::CXX).getPreprocessed())
+    .Case("cui", InputKind(InputKind::CUDA).getPreprocessed())
+    .Case("m", InputKind::ObjC)
+    .Case("mi", InputKind(InputKind::ObjC).getPreprocessed())
+    .Cases("mm", "M", InputKind::ObjCXX)
+    .Case("mii", InputKind(InputKind::ObjCXX).getPreprocessed())
+    .Cases("C", "cc", "cp", InputKind::CXX)
+    .Cases("cpp", "CPP", "c++", "cxx", "hpp", InputKind::CXX)
+    .Case("cppm", InputKind::CXX)
+    .Case("iim", InputKind(InputKind::CXX).getPreprocessed())
+    .Case("cl", InputKind::OpenCL)
+    .Case("cu", InputKind::CUDA)
+    .Cases("ll", "bc", InputKind::LLVM_IR)
+    .Default(InputKind::Unknown);
 }
diff --git a/lib/Frontend/InitPreprocessor.cpp b/lib/Frontend/InitPreprocessor.cpp
index 0dd04e8a8fff..9257dcae84cd 100644
--- a/lib/Frontend/InitPreprocessor.cpp
+++ b/lib/Frontend/InitPreprocessor.cpp
@@ -1041,6 +1041,8 @@ void clang::InitializePreprocessor(
 
   // Install things like __POWERPC__, __GNUC__, etc into the macro table.
   if (InitOpts.UsePredefines) {
+    // FIXME: This will create multiple definitions for most of the predefined
+    // macros. This is not the right way to handle this.
     if (LangOpts.CUDA && PP.getAuxTargetInfo())
       InitializePredefinedMacros(*PP.getAuxTargetInfo(), LangOpts, FEOpts,
                                  Builder);
diff --git a/lib/Frontend/LangStandards.cpp b/lib/Frontend/LangStandards.cpp
index f133327f4298..47023e58fa0b 100644
--- a/lib/Frontend/LangStandards.cpp
+++ b/lib/Frontend/LangStandards.cpp
@@ -13,15 +13,15 @@
 using namespace clang;
 using namespace clang::frontend;
 
-#define LANGSTANDARD(id, name, desc, features) \
-  static const LangStandard Lang_##id = { name, desc, features };
+#define LANGSTANDARD(id, name, lang, desc, features) \
+static const LangStandard Lang_##id = { name, desc, features, InputKind::lang };
 #include "clang/Frontend/LangStandards.def"
 
 const LangStandard &LangStandard::getLangStandardForKind(Kind K) {
   switch (K) {
   case lang_unspecified:
     llvm::report_fatal_error("getLangStandardForKind() on unspecified kind");
-#define LANGSTANDARD(id, name, desc, features) \
+#define LANGSTANDARD(id, name, lang, desc, features) \
     case lang_##id: return Lang_##id;
 #include "clang/Frontend/LangStandards.def"
   }
@@ -30,7 +30,7 @@ const LangStandard &LangStandard::getLangStandardForKind(Kind K) {
 
 const LangStandard *LangStandard::getLangStandardForName(StringRef Name) {
   Kind K = llvm::StringSwitch<Kind>(Name)
-#define LANGSTANDARD(id, name, desc, features) \
+#define LANGSTANDARD(id, name, lang, desc, features) \
     .Case(name, lang_##id)
 #include "clang/Frontend/LangStandards.def"
     .Default(lang_unspecified);
diff --git a/lib/Frontend/PrintPreprocessedOutput.cpp b/lib/Frontend/PrintPreprocessedOutput.cpp
index d48b952ef203..ffedf3cac847 100644
--- a/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -172,7 +172,8 @@ public:
 
   /// MacroUndefined - This hook is called whenever a macro #undef is seen.
   void MacroUndefined(const Token &MacroNameTok,
-                      const MacroDefinition &MD) override;
+                      const MacroDefinition &MD,
+                      const MacroDirective *Undef) override;
 };
 }  // end anonymous namespace
 
@@ -323,43 +324,50 @@ void PrintPPOutputPPCallbacks::InclusionDirective(SourceLocation HashLoc,
                                                   StringRef SearchPath,
                                                   StringRef RelativePath,
                                                   const Module *Imported) {
-  if (Imported) {
-    // When preprocessing, turn implicit imports into @imports.
-    // FIXME: This is a stop-gap until a more comprehensive "preprocessing with
-    // modules" solution is introduced.
+  // In -dI mode, dump #include directives prior to dumping their content or
+  // interpretation.
+  if (DumpIncludeDirectives) {
     startNewLineIfNeeded();
     MoveToLine(HashLoc);
-    if (PP.getLangOpts().ObjC2) {
-      OS << "@import " << Imported->getFullModuleName() << ";"
-         << " /* clang -E: implicit import for \"" << File->getName()
-         << "\" */";
-    } else {
-      const std::string TokenText = PP.getSpelling(IncludeTok);
-      assert(!TokenText.empty());
-      OS << "#" << TokenText << " "
-         << (IsAngled ? '<' : '"')
-         << FileName
-         << (IsAngled ? '>' : '"')
-         << " /* clang -E: implicit import for module "
-         << Imported->getFullModuleName() << " */";
-    }
-    // Since we want a newline after the @import, but not a #<line>, start a new
-    // line immediately.
-    EmittedTokensOnThisLine = true;
+    const std::string TokenText = PP.getSpelling(IncludeTok);
+    assert(!TokenText.empty());
+    OS << "#" << TokenText << " "
+       << (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')
+       << " /* clang -E -dI */";
+    setEmittedDirectiveOnThisLine();
     startNewLineIfNeeded();
-  } else {
-    // Not a module import; it's a more vanilla inclusion of some file using one
-    // of: #include, #import, #include_next, #include_macros.
-    if (DumpIncludeDirectives) {
+  }
+
+  // When preprocessing, turn implicit imports into module import pragmas.
+  if (Imported) {
+    switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
+    case tok::pp_include:
+    case tok::pp_import:
+    case tok::pp_include_next:
       startNewLineIfNeeded();
       MoveToLine(HashLoc);
-      const std::string TokenText = PP.getSpelling(IncludeTok);
-      assert(!TokenText.empty());
-      OS << "#" << TokenText << " "
+      OS << "#pragma clang module import " << Imported->getFullModuleName()
+         << " /* clang -E: implicit import for "
+         << "#" << PP.getSpelling(IncludeTok) << " "
          << (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')
-         << " /* clang -E -dI */";
-      setEmittedDirectiveOnThisLine();
+         << " */";
+      // Since we want a newline after the pragma, but not a #<line>, start a
+      // new line immediately.
+      EmittedTokensOnThisLine = true;
       startNewLineIfNeeded();
+      break;
+
+    case tok::pp___include_macros:
+      // #__include_macros has no effect on a user of a preprocessed source
+      // file; the only effect is on preprocessing.
+      //
+      // FIXME: That's not *quite* true: it causes the module in question to
+      // be loaded, which can affect downstream diagnostics.
+      break;
+
+    default:
+      llvm_unreachable("unknown include directive kind");
+      break;
     }
   }
 }
@@ -389,7 +397,8 @@ void PrintPPOutputPPCallbacks::MacroDefined(const Token &MacroNameTok,
 }
 
 void PrintPPOutputPPCallbacks::MacroUndefined(const Token &MacroNameTok,
-                                              const MacroDefinition &MD) {
+                                              const MacroDefinition &MD,
+                                              const MacroDirective *Undef) {
   // Only print out macro definitions in -dD mode.
   if (!DumpDefines) return;
 
@@ -773,26 +782,33 @@ void clang::DoPrintPreprocessedInput(Preprocessor &PP, raw_ostream *OS,
 
   // Expand macros in pragmas with -fms-extensions.  The assumption is that
   // the majority of pragmas in such a file will be Microsoft pragmas.
-  PP.AddPragmaHandler(new UnknownPragmaHandler(
-      "#pragma", Callbacks,
+  // Remember the handlers we will add so that we can remove them later.
+  std::unique_ptr<UnknownPragmaHandler> MicrosoftExtHandler(
+      new UnknownPragmaHandler(
+          "#pragma", Callbacks,
+          /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
+
+  std::unique_ptr<UnknownPragmaHandler> GCCHandler(new UnknownPragmaHandler(
+      "#pragma GCC", Callbacks,
       /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
-  PP.AddPragmaHandler(
-      "GCC", new UnknownPragmaHandler(
-                 "#pragma GCC", Callbacks,
-                 /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
-  PP.AddPragmaHandler(
-      "clang", new UnknownPragmaHandler(
-                   "#pragma clang", Callbacks,
-                   /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
+
+  std::unique_ptr<UnknownPragmaHandler> ClangHandler(new UnknownPragmaHandler(
+      "#pragma clang", Callbacks,
+      /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
+
+  PP.AddPragmaHandler(MicrosoftExtHandler.get());
+  PP.AddPragmaHandler("GCC", GCCHandler.get());
+  PP.AddPragmaHandler("clang", ClangHandler.get());
 
   // The tokens after pragma omp need to be expanded.
   //
   //  OpenMP [2.1, Directive format]
   //  Preprocessing tokens following the #pragma omp are subject to macro
   //  replacement.
-  PP.AddPragmaHandler("omp",
-                      new UnknownPragmaHandler("#pragma omp", Callbacks,
-                                               /*RequireTokenExpansion=*/true));
+  std::unique_ptr<UnknownPragmaHandler> OpenMPHandler(
+      new UnknownPragmaHandler("#pragma omp", Callbacks,
+                               /*RequireTokenExpansion=*/true));
+  PP.AddPragmaHandler("omp", OpenMPHandler.get());
 
   PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callbacks));
 
@@ -820,4 +836,11 @@ void clang::DoPrintPreprocessedInput(Preprocessor &PP, raw_ostream *OS,
   // Read all the preprocessed tokens, printing them out to the stream.
   PrintPreprocessedTokens(PP, Tok, Callbacks, *OS);
   *OS << '\n';
+
+  // Remove the handlers we just added to leave the preprocessor in a sane state
+  // so that it can be reused (for example by a clang::Parser instance).
+  PP.RemovePragmaHandler(MicrosoftExtHandler.get());
+  PP.RemovePragmaHandler("GCC", GCCHandler.get());
+  PP.RemovePragmaHandler("clang", ClangHandler.get());
+  PP.RemovePragmaHandler("omp", OpenMPHandler.get());
 }
diff --git a/lib/Frontend/Rewrite/InclusionRewriter.cpp b/lib/Frontend/Rewrite/InclusionRewriter.cpp
index d953da2e4fd2..ee61f76d029d 100644
--- a/lib/Frontend/Rewrite/InclusionRewriter.cpp
+++ b/lib/Frontend/Rewrite/InclusionRewriter.cpp
@@ -52,7 +52,7 @@ class InclusionRewriter : public PPCallbacks {
 public:
   InclusionRewriter(Preprocessor &PP, raw_ostream &OS, bool ShowLineMarkers,
                     bool UseLineDirectives);
-  bool Process(FileID FileId, SrcMgr::CharacteristicKind FileType);
+  void Process(FileID FileId, SrcMgr::CharacteristicKind FileType);
   void setPredefinesBuffer(const llvm::MemoryBuffer *Buf) {
     PredefinesBuffer = Buf;
   }
@@ -132,7 +132,7 @@ void InclusionRewriter::WriteLineInfo(StringRef Filename, int Line,
 }
 
 void InclusionRewriter::WriteImplicitModuleImport(const Module *Mod) {
-  OS << "@import " << Mod->getFullModuleName() << ";"
+  OS << "#pragma clang module import " << Mod->getFullModuleName()
      << " /* clang -frewrite-includes: implicit import */" << MainEOL;
 }
 
@@ -392,7 +392,7 @@ bool InclusionRewriter::HandleHasInclude(
   // FIXME: Why don't we call PP.LookupFile here?
   const FileEntry *File = PP.getHeaderSearchInfo().LookupFile(
       Filename, SourceLocation(), isAngled, nullptr, CurDir, Includers, nullptr,
-      nullptr, nullptr, nullptr, false);
+      nullptr, nullptr, nullptr, nullptr);
 
   FileExists = File != nullptr;
   return true;
@@ -400,9 +400,8 @@ bool InclusionRewriter::HandleHasInclude(
 
 /// Use a raw lexer to analyze \p FileId, incrementally copying parts of it
 /// and including content of included files recursively.
-bool InclusionRewriter::Process(FileID FileId,
-                                SrcMgr::CharacteristicKind FileType)
-{
+void InclusionRewriter::Process(FileID FileId,
+                                SrcMgr::CharacteristicKind FileType) {
   bool Invalid;
   const MemoryBuffer &FromFile = *SM.getBuffer(FileId, &Invalid);
   assert(!Invalid && "Attempting to process invalid inclusion");
@@ -419,7 +418,7 @@ bool InclusionRewriter::Process(FileID FileId,
     WriteLineInfo(FileName, 1, FileType, " 1");
 
   if (SM.getFileIDSize(FileId) == 0)
-    return false;
+    return;
 
   // The next byte to be copied from the source file, which may be non-zero if
   // the lexer handled a BOM.
@@ -450,19 +449,14 @@ bool InclusionRewriter::Process(FileID FileId,
               WriteLineInfo(FileName, Line - 1, FileType, "");
             StringRef LineInfoExtra;
             SourceLocation Loc = HashToken.getLocation();
-            if (const Module *Mod = PP.getLangOpts().ObjC2
-                                        ? FindModuleAtLocation(Loc)
-                                        : nullptr)
+            if (const Module *Mod = FindModuleAtLocation(Loc))
               WriteImplicitModuleImport(Mod);
             else if (const IncludedFile *Inc = FindIncludeAtLocation(Loc)) {
-              // include and recursively process the file
-              if (Process(Inc->Id, Inc->FileType)) {
-                // and set lineinfo back to this file, if the nested one was
-                // actually included
-                // `2' indicates returning to a file (after having included
-                // another file.
-                LineInfoExtra = " 2";
-              }
+              // Include and recursively process the file.
+              Process(Inc->Id, Inc->FileType);
+              // Add line marker to indicate we're returning from an included
+              // file.
+              LineInfoExtra = " 2";
             }
             // fix up lineinfo (since commented out directive changed line
             // numbers) for inclusions that were skipped due to header guards
@@ -571,7 +565,6 @@ bool InclusionRewriter::Process(FileID FileId,
   OutputContentUpTo(FromFile, NextToWrite,
                     SM.getFileOffset(SM.getLocForEndOfFile(FileId)), LocalEOL,
                     Line, /*EnsureNewline=*/true);
-  return true;
 }
 
 /// InclusionRewriterInInput - Implement -frewrite-includes mode.
diff --git a/lib/Frontend/VerifyDiagnosticConsumer.cpp b/lib/Frontend/VerifyDiagnosticConsumer.cpp
index ae16ea177ffe..427d15ed703a 100644
--- a/lib/Frontend/VerifyDiagnosticConsumer.cpp
+++ b/lib/Frontend/VerifyDiagnosticConsumer.cpp
@@ -400,7 +400,7 @@ static bool ParseDirective(StringRef S, ExpectedData *ED, SourceManager &SM,
         const DirectoryLookup *CurDir;
         const FileEntry *FE =
             PP->LookupFile(Pos, Filename, false, nullptr, nullptr, CurDir,
-                           nullptr, nullptr, nullptr);
+                           nullptr, nullptr, nullptr, nullptr);
         if (!FE) {
           Diags.Report(Pos.getLocWithOffset(PH.C-PH.Begin),
                        diag::err_verify_missing_file) << Filename << KindStr;
diff --git a/lib/Headers/avx512fintrin.h b/lib/Headers/avx512fintrin.h
index d8535f765889..b556d04efbb7 100644
--- a/lib/Headers/avx512fintrin.h
+++ b/lib/Headers/avx512fintrin.h
@@ -528,6 +528,116 @@ _mm512_mask2int(__mmask16 __a)
   return (int)__a;
 }
 
+/// \brief Constructs a 512-bit floating-point vector of [8 x double] from a
+///    128-bit floating-point vector of [2 x double]. The lower 128 bits
+///    contain the value of the source vector. The upper 384 bits are set
+///    to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 128-bit vector of [2 x double].
+/// \returns A 512-bit floating-point vector of [8 x double]. The lower 128 bits
+///    contain the value of the parameter. The upper 384 bits are set to zero.
+static __inline __m512d __DEFAULT_FN_ATTRS
+_mm512_zextpd128_pd512(__m128d __a)
+{
+  return __builtin_shufflevector((__v2df)__a, (__v2df)_mm_setzero_pd(), 0, 1, 2, 3, 2, 3, 2, 3);
+}
+
+/// \brief Constructs a 512-bit floating-point vector of [8 x double] from a
+///    256-bit floating-point vector of [4 x double]. The lower 256 bits
+///    contain the value of the source vector. The upper 256 bits are set
+///    to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 256-bit vector of [4 x double].
+/// \returns A 512-bit floating-point vector of [8 x double]. The lower 256 bits
+///    contain the value of the parameter. The upper 256 bits are set to zero.
+static __inline __m512d __DEFAULT_FN_ATTRS
+_mm512_zextpd256_pd512(__m256d __a)
+{
+  return __builtin_shufflevector((__v4df)__a, (__v4df)_mm256_setzero_pd(), 0, 1, 2, 3, 4, 5, 6, 7);
+}
+
+/// \brief Constructs a 512-bit floating-point vector of [16 x float] from a
+///    128-bit floating-point vector of [4 x float]. The lower 128 bits contain
+///    the value of the source vector. The upper 384 bits are set to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 128-bit vector of [4 x float].
+/// \returns A 512-bit floating-point vector of [16 x float]. The lower 128 bits
+///    contain the value of the parameter. The upper 384 bits are set to zero.
+static __inline __m512 __DEFAULT_FN_ATTRS
+_mm512_zextps128_ps512(__m128 __a)
+{
+  return __builtin_shufflevector((__v4sf)__a, (__v4sf)_mm_setzero_ps(), 0, 1, 2, 3, 4, 5, 6, 7, 4, 5, 6, 7, 4, 5, 6, 7);
+}
+
+/// \brief Constructs a 512-bit floating-point vector of [16 x float] from a
+///    256-bit floating-point vector of [8 x float]. The lower 256 bits contain
+///    the value of the source vector. The upper 256 bits are set to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 256-bit vector of [8 x float].
+/// \returns A 512-bit floating-point vector of [16 x float]. The lower 256 bits
+///    contain the value of the parameter. The upper 256 bits are set to zero.
+static __inline __m512 __DEFAULT_FN_ATTRS
+_mm512_zextps256_ps512(__m256 __a)
+{
+  return __builtin_shufflevector((__v8sf)__a, (__v8sf)_mm256_setzero_ps(), 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+}
+
+/// \brief Constructs a 512-bit integer vector from a 128-bit integer vector.
+///    The lower 128 bits contain the value of the source vector. The upper
+///    384 bits are set to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 128-bit integer vector.
+/// \returns A 512-bit integer vector. The lower 128 bits contain the value of
+///    the parameter. The upper 384 bits are set to zero.
+static __inline __m512i __DEFAULT_FN_ATTRS
+_mm512_zextsi128_si512(__m128i __a)
+{
+  return __builtin_shufflevector((__v2di)__a, (__v2di)_mm_setzero_si128(), 0, 1, 2, 3, 2, 3, 2, 3);
+}
+
+/// \brief Constructs a 512-bit integer vector from a 256-bit integer vector.
+///    The lower 256 bits contain the value of the source vector. The upper
+///    256 bits are set to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 256-bit integer vector.
+/// \returns A 512-bit integer vector. The lower 256 bits contain the value of
+///    the parameter. The upper 256 bits are set to zero.
+static __inline __m512i __DEFAULT_FN_ATTRS
+_mm512_zextsi256_si512(__m256i __a)
+{
+  return __builtin_shufflevector((__v4di)__a, (__v4di)_mm256_setzero_si256(), 0, 1, 2, 3, 4, 5, 6, 7);
+}
+
 /* Bitwise operators */
 static __inline__ __m512i __DEFAULT_FN_ATTRS
 _mm512_and_epi32(__m512i __a, __m512i __b)
diff --git a/lib/Headers/avxintrin.h b/lib/Headers/avxintrin.h
index 5381878a5da3..cdb7aa4fb626 100644
--- a/lib/Headers/avxintrin.h
+++ b/lib/Headers/avxintrin.h
@@ -4523,6 +4523,61 @@ _mm256_castsi128_si256(__m128i __a)
   return __builtin_shufflevector((__v2di)__a, (__v2di)__a, 0, 1, -1, -1);
 }
 
+/// \brief Constructs a 256-bit floating-point vector of [4 x double] from a
+///    128-bit floating-point vector of [2 x double]. The lower 128 bits
+///    contain the value of the source vector. The upper 128 bits are set
+///    to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 128-bit vector of [2 x double].
+/// \returns A 256-bit floating-point vector of [4 x double]. The lower 128 bits
+///    contain the value of the parameter. The upper 128 bits are set to zero.
+static __inline __m256d __DEFAULT_FN_ATTRS
+_mm256_zextpd128_pd256(__m128d __a)
+{
+  return __builtin_shufflevector((__v2df)__a, (__v2df)_mm_setzero_pd(), 0, 1, 2, 3);
+}
+
+/// \brief Constructs a 256-bit floating-point vector of [8 x float] from a
+///    128-bit floating-point vector of [4 x float]. The lower 128 bits contain
+///    the value of the source vector. The upper 128 bits are set to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 128-bit vector of [4 x float].
+/// \returns A 256-bit floating-point vector of [8 x float]. The lower 128 bits
+///    contain the value of the parameter. The upper 128 bits are set to zero.
+static __inline __m256 __DEFAULT_FN_ATTRS
+_mm256_zextps128_ps256(__m128 __a)
+{
+  return __builtin_shufflevector((__v4sf)__a, (__v4sf)_mm_setzero_ps(), 0, 1, 2, 3, 4, 5, 6, 7);
+}
+
+/// \brief Constructs a 256-bit integer vector from a 128-bit integer vector.
+///    The lower 128 bits contain the value of the source vector. The upper
+///    128 bits are set to zero.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic has no corresponding instruction.
+///
+/// \param __a
+///    A 128-bit integer vector.
+/// \returns A 256-bit integer vector. The lower 128 bits contain the value of
+///    the parameter. The upper 128 bits are set to zero.
+static __inline __m256i __DEFAULT_FN_ATTRS
+_mm256_zextsi128_si256(__m128i __a)
+{
+  return __builtin_shufflevector((__v2di)__a, (__v2di)_mm_setzero_si128(), 0, 1, 2, 3);
+}
+
 /*
    Vector insert.
    We use macros rather than inlines because we only want to accept
diff --git a/lib/Headers/bmiintrin.h b/lib/Headers/bmiintrin.h
index 488eb2dbd3d4..e590cf8bc1ae 100644
--- a/lib/Headers/bmiintrin.h
+++ b/lib/Headers/bmiintrin.h
@@ -28,107 +28,17 @@
 #ifndef __BMIINTRIN_H
 #define __BMIINTRIN_H
 
-/// \brief Counts the number of trailing zero bits in the operand.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned short _tzcnt_u16(unsigned short a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> TZCNT </c> instruction.
-///
-/// \param a
-///    An unsigned 16-bit integer whose trailing zeros are to be counted.
-/// \returns An unsigned 16-bit integer containing the number of trailing zero
-///    bits in the operand.
 #define _tzcnt_u16(a)     (__tzcnt_u16((a)))
 
-/// \brief Performs a bitwise AND of the second operand with the one's
-///    complement of the first operand.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned int _andn_u32(unsigned int a, unsigned int b);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> ANDN </c> instruction.
-///
-/// \param a
-///    An unsigned integer containing one of the operands.
-/// \param b
-///    An unsigned integer containing one of the operands.
-/// \returns An unsigned integer containing the bitwise AND of the second
-///    operand with the one's complement of the first operand.
 #define _andn_u32(a, b)   (__andn_u32((a), (b)))
 
 /* _bextr_u32 != __bextr_u32 */
-/// \brief Clears all bits in the source except for the least significant bit
-///    containing a value of 1 and returns the result.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned int _blsi_u32(unsigned int a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> BLSI </c> instruction.
-///
-/// \param a
-///    An unsigned integer whose bits are to be cleared.
-/// \returns An unsigned integer containing the result of clearing the bits from
-///    the source operand.
 #define _blsi_u32(a)      (__blsi_u32((a)))
 
-/// \brief Creates a mask whose bits are set to 1, using bit 0 up to and
-///    including the least siginificant bit that is set to 1 in the source
-///    operand and returns the result.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned int _blsmsk_u32(unsigned int a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> BLSMSK </c> instruction.
-///
-/// \param a
-///    An unsigned integer used to create the mask.
-/// \returns An unsigned integer containing the newly created mask.
 #define _blsmsk_u32(a)    (__blsmsk_u32((a)))
 
-/// \brief Clears the least siginificant bit that is set to 1 in the source
-///    operand and returns the result.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned int _blsr_u32(unsigned int a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> BLSR </c> instruction.
-///
-/// \param a
-///    An unsigned integer containing the operand to be cleared.
-/// \returns An unsigned integer containing the result of clearing the source
-///    operand.
 #define _blsr_u32(a)      (__blsr_u32((a)))
 
-/// \brief Counts the number of trailing zero bits in the operand.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned int _tzcnt_u32(unsigned int a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> TZCNT </c> instruction.
-///
-/// \param a
-///    An unsigned 32-bit integer whose trailing zeros are to be counted.
-/// \returns An unsigned 32-bit integer containing the number of trailing zero
-///    bits in the operand.
 #define _tzcnt_u32(a)     (__tzcnt_u32((a)))
 
 /* Define the default attributes for the functions in this file. */
@@ -305,91 +215,15 @@ _mm_tzcnt_32(unsigned int __X)
 
 #ifdef __x86_64__
 
-/// \brief Performs a bitwise AND of the second operand with the one's
-///    complement of the first operand.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned long long _andn_u64 (unsigned long long a, unsigned long long b);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> ANDN </c> instruction.
-///
-/// \param a
-///    An unsigned 64-bit integer containing one of the operands.
-/// \param b
-///    An unsigned 64-bit integer containing one of the operands.
-/// \returns An unsigned 64-bit integer containing the bitwise AND of the second
-///    operand with the one's complement of the first operand.
 #define _andn_u64(a, b)   (__andn_u64((a), (b)))
 
 /* _bextr_u64 != __bextr_u64 */
-/// \brief Clears all bits in the source except for the least significant bit
-///    containing a value of 1 and returns the result.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned long long _blsi_u64(unsigned long long a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> BLSI </c> instruction.
-///
-/// \param a
-///    An unsigned 64-bit integer whose bits are to be cleared.
-/// \returns An unsigned 64-bit integer containing the result of clearing the
-///    bits from the source operand.
 #define _blsi_u64(a)      (__blsi_u64((a)))
 
-/// \brief Creates a mask whose bits are set to 1, using bit 0 up to and
-///    including the least siginificant bit that is set to 1 in the source
-///    operand and returns the result.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned long long _blsmsk_u64(unsigned long long a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> BLSMSK </c> instruction.
-///
-/// \param a
-///    An unsigned 64-bit integer used to create the mask.
-/// \returns A unsigned 64-bit integer containing the newly created mask.
 #define _blsmsk_u64(a)    (__blsmsk_u64((a)))
 
-/// \brief Clears the least siginificant bit that is set to 1 in the source
-///    operand and returns the result.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned long long _blsr_u64(unsigned long long a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> BLSR </c> instruction.
-///
-/// \param a
-///    An unsigned 64-bit integer containing the operand to be cleared.
-/// \returns An unsigned 64-bit integer containing the result of clearing the
-///    source operand.
 #define _blsr_u64(a)      (__blsr_u64((a)))
 
-/// \brief Counts the number of trailing zero bits in the operand.
-///
-/// \headerfile <x86intrin.h>
-///
-/// \code
-/// unsigned long long _tzcnt_u64(unsigned long long a);
-/// \endcode
-///
-/// This intrinsic corresponds to the <c> TZCNT </c> instruction.
-///
-/// \param a
-///    An unsigned 64-bit integer whose trailing zeros are to be counted.
-/// \returns An unsigned 64-bit integer containing the number of trailing zero
-///    bits in the operand.
 #define _tzcnt_u64(a)     (__tzcnt_u64((a)))
 
 /// \brief Performs a bitwise AND of the second operand with the one's
diff --git a/lib/Headers/emmintrin.h b/lib/Headers/emmintrin.h
index 0dfa6a9fbc1f..13b0db22ec44 100644
--- a/lib/Headers/emmintrin.h
+++ b/lib/Headers/emmintrin.h
@@ -1750,6 +1750,24 @@ _mm_set1_pd(double __w)
   return (__m128d){ __w, __w };
 }
 
+/// \brief Constructs a 128-bit floating-point vector of [2 x double], with each
+///    of the two double-precision floating-point vector elements set to the
+///    specified double-precision floating-point value.
+///
+/// \headerfile <x86intrin.h>
+///
+/// This intrinsic corresponds to the <c> VMOVDDUP / MOVLHPS </c> instruction.
+///
+/// \param __w
+///    A double-precision floating-point value used to initialize each vector
+///    element of the result.
+/// \returns An initialized 128-bit floating-point vector of [2 x double].
+static __inline__ __m128d __DEFAULT_FN_ATTRS
+_mm_set_pd1(double __w)
+{
+  return _mm_set1_pd(__w);
+}
+
 /// \brief Constructs a 128-bit floating-point vector of [2 x double]
 ///    initialized with the specified double-precision floating-point values.
 ///
diff --git a/lib/Headers/stdint.h b/lib/Headers/stdint.h
index 3f2fcbc57023..c48815314b51 100644
--- a/lib/Headers/stdint.h
+++ b/lib/Headers/stdint.h
@@ -255,19 +255,16 @@ typedef __uint_least8_t uint_fast8_t;
  */
 #define __stdint_join3(a,b,c) a ## b ## c
 
-#define  __intn_t(n) __stdint_join3( int, n, _t)
-#define __uintn_t(n) __stdint_join3(uint, n, _t)
-
 #ifndef _INTPTR_T
 #ifndef __intptr_t_defined
-typedef  __intn_t(__INTPTR_WIDTH__)  intptr_t;
+typedef __INTPTR_TYPE__ intptr_t;
 #define __intptr_t_defined
 #define _INTPTR_T
 #endif
 #endif
 
 #ifndef _UINTPTR_T
-typedef __uintn_t(__INTPTR_WIDTH__) uintptr_t;
+typedef __UINTPTR_TYPE__ uintptr_t;
 #define _UINTPTR_T
 #endif
 
@@ -659,12 +656,12 @@ typedef __UINTMAX_TYPE__ uintmax_t;
 /* C99 7.18.2.4 Limits of integer types capable of holding object pointers. */
 /* C99 7.18.3 Limits of other integer types. */
 
-#define  INTPTR_MIN  __INTN_MIN(__INTPTR_WIDTH__)
-#define  INTPTR_MAX  __INTN_MAX(__INTPTR_WIDTH__)
-#define UINTPTR_MAX __UINTN_MAX(__INTPTR_WIDTH__)
-#define PTRDIFF_MIN  __INTN_MIN(__PTRDIFF_WIDTH__)
-#define PTRDIFF_MAX  __INTN_MAX(__PTRDIFF_WIDTH__)
-#define    SIZE_MAX __UINTN_MAX(__SIZE_WIDTH__)
+#define  INTPTR_MIN  (-__INTPTR_MAX__-1)
+#define  INTPTR_MAX    __INTPTR_MAX__
+#define UINTPTR_MAX   __UINTPTR_MAX__
+#define PTRDIFF_MIN (-__PTRDIFF_MAX__-1)
+#define PTRDIFF_MAX   __PTRDIFF_MAX__
+#define    SIZE_MAX      __SIZE_MAX__
 
 /* ISO9899:2011 7.20 (C11 Annex K): Define RSIZE_MAX if __STDC_WANT_LIB_EXT1__
  * is enabled. */
@@ -673,9 +670,9 @@ typedef __UINTMAX_TYPE__ uintmax_t;
 #endif
 
 /* C99 7.18.2.5 Limits of greatest-width integer types. */
-#define INTMAX_MIN   __INTN_MIN(__INTMAX_WIDTH__)
-#define INTMAX_MAX   __INTN_MAX(__INTMAX_WIDTH__)
-#define UINTMAX_MAX __UINTN_MAX(__INTMAX_WIDTH__)
+#define  INTMAX_MIN (-__INTMAX_MAX__-1)
+#define  INTMAX_MAX   __INTMAX_MAX__
+#define UINTMAX_MAX  __UINTMAX_MAX__
 
 /* C99 7.18.3 Limits of other integer types. */
 #define SIG_ATOMIC_MIN __INTN_MIN(__SIG_ATOMIC_WIDTH__)
@@ -700,8 +697,8 @@ typedef __UINTMAX_TYPE__ uintmax_t;
 #endif
 
 /* 7.18.4.2 Macros for greatest-width integer constants. */
-#define INTMAX_C(v)   __INTN_C(__INTMAX_WIDTH__, v)
-#define UINTMAX_C(v) __UINTN_C(__INTMAX_WIDTH__, v)
+#define  INTMAX_C(v) __int_c(v,  __INTMAX_C_SUFFIX__)
+#define UINTMAX_C(v) __int_c(v, __UINTMAX_C_SUFFIX__)
 
 #endif /* __STDC_HOSTED__ */
 #endif /* __CLANG_STDINT_H */
diff --git a/lib/Index/IndexDecl.cpp b/lib/Index/IndexDecl.cpp
index c1eed1684cbd..e8b2f1052d73 100644
--- a/lib/Index/IndexDecl.cpp
+++ b/lib/Index/IndexDecl.cpp
@@ -481,17 +481,17 @@ public:
       return true;
 
     assert(D->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize);
+    SymbolRoleSet AccessorMethodRoles =
+      SymbolRoleSet(SymbolRole::Dynamic) | SymbolRoleSet(SymbolRole::Implicit);
     if (ObjCMethodDecl *MD = PD->getGetterMethodDecl()) {
       if (MD->isPropertyAccessor() &&
           !hasUserDefined(MD, Container))
-        IndexCtx.handleDecl(MD, Loc, SymbolRoleSet(SymbolRole::Implicit), {},
-                            Container);
+        IndexCtx.handleDecl(MD, Loc, AccessorMethodRoles, {}, Container);
     }
     if (ObjCMethodDecl *MD = PD->getSetterMethodDecl()) {
       if (MD->isPropertyAccessor() &&
           !hasUserDefined(MD, Container))
-        IndexCtx.handleDecl(MD, Loc, SymbolRoleSet(SymbolRole::Implicit), {},
-                            Container);
+        IndexCtx.handleDecl(MD, Loc, AccessorMethodRoles, {}, Container);
     }
     if (ObjCIvarDecl *IvarD = D->getPropertyIvarDecl()) {
       if (IvarD->getSynthesize()) {
diff --git a/lib/Index/USRGeneration.cpp b/lib/Index/USRGeneration.cpp
index ed469f677a34..044edf715fc2 100644
--- a/lib/Index/USRGeneration.cpp
+++ b/lib/Index/USRGeneration.cpp
@@ -811,7 +811,13 @@ void USRGenerator::VisitType(QualType T) {
       T = InjT->getInjectedSpecializationType();
       continue;
     }
-    
+    if (const auto *VT = T->getAs<VectorType>()) {
+      Out << (T->isExtVectorType() ? ']' : '[');
+      Out << VT->getNumElements();
+      T = VT->getElementType();
+      continue;
+    }
+
     // Unhandled type.
     Out << ' ';
     break;
diff --git a/lib/Lex/HeaderSearch.cpp b/lib/Lex/HeaderSearch.cpp
index 4ee38719289b..bd425a07c33a 100644
--- a/lib/Lex/HeaderSearch.cpp
+++ b/lib/Lex/HeaderSearch.cpp
@@ -624,7 +624,10 @@ const FileEntry *HeaderSearch::LookupFile(
     ArrayRef<std::pair<const FileEntry *, const DirectoryEntry *>> Includers,
     SmallVectorImpl<char> *SearchPath, SmallVectorImpl<char> *RelativePath,
     Module *RequestingModule, ModuleMap::KnownHeader *SuggestedModule,
-    bool SkipCache, bool BuildSystemModule) {
+    bool *IsMapped, bool SkipCache, bool BuildSystemModule) {
+  if (IsMapped)
+    *IsMapped = false;
+
   if (SuggestedModule)
     *SuggestedModule = ModuleMap::KnownHeader();
     
@@ -754,8 +757,11 @@ const FileEntry *HeaderSearch::LookupFile(
   if (!SkipCache && CacheLookup.StartIdx == i+1) {
     // Skip querying potentially lots of directories for this lookup.
     i = CacheLookup.HitIdx;
-    if (CacheLookup.MappedName)
+    if (CacheLookup.MappedName) {
       Filename = CacheLookup.MappedName;
+      if (IsMapped)
+        *IsMapped = true;
+    }
   } else {
     // Otherwise, this is the first query, or the previous query didn't match
     // our search start.  We will fill in our found location below, so prime the
@@ -776,6 +782,8 @@ const FileEntry *HeaderSearch::LookupFile(
     if (HasBeenMapped) {
       CacheLookup.MappedName =
           copyString(Filename, LookupFileCache.getAllocator());
+      if (IsMapped)
+        *IsMapped = true;
     }
     if (!FE) continue;
 
@@ -839,7 +847,7 @@ const FileEntry *HeaderSearch::LookupFile(
       const FileEntry *FE =
           LookupFile(ScratchFilename, IncludeLoc, /*isAngled=*/true, FromDir,
                      CurDir, Includers.front(), SearchPath, RelativePath,
-                     RequestingModule, SuggestedModule);
+                     RequestingModule, SuggestedModule, IsMapped);
 
       if (checkMSVCHeaderSearch(Diags, MSFE, FE, IncludeLoc)) {
         if (SuggestedModule)
diff --git a/lib/Lex/MacroInfo.cpp b/lib/Lex/MacroInfo.cpp
index 924613dcb840..bec434085e3a 100644
--- a/lib/Lex/MacroInfo.cpp
+++ b/lib/Lex/MacroInfo.cpp
@@ -33,7 +33,7 @@ MacroInfo::MacroInfo(SourceLocation DefLoc)
     UsedForHeaderGuard(false) {
 }
 
-unsigned MacroInfo::getDefinitionLengthSlow(SourceManager &SM) const {
+unsigned MacroInfo::getDefinitionLengthSlow(const SourceManager &SM) const {
   assert(!IsDefinitionLengthCached);
   IsDefinitionLengthCached = true;
 
diff --git a/lib/Lex/PPDirectives.cpp b/lib/Lex/PPDirectives.cpp
index 8a56ddf23699..4826e399afda 100644
--- a/lib/Lex/PPDirectives.cpp
+++ b/lib/Lex/PPDirectives.cpp
@@ -752,16 +752,11 @@ Preprocessor::getModuleHeaderToIncludeForDiagnostics(SourceLocation IncLoc,
 }
 
 const FileEntry *Preprocessor::LookupFile(
-    SourceLocation FilenameLoc,
-    StringRef Filename,
-    bool isAngled,
-    const DirectoryLookup *FromDir,
-    const FileEntry *FromFile,
-    const DirectoryLookup *&CurDir,
-    SmallVectorImpl<char> *SearchPath,
+    SourceLocation FilenameLoc, StringRef Filename, bool isAngled,
+    const DirectoryLookup *FromDir, const FileEntry *FromFile,
+    const DirectoryLookup *&CurDir, SmallVectorImpl<char> *SearchPath,
     SmallVectorImpl<char> *RelativePath,
-    ModuleMap::KnownHeader *SuggestedModule,
-    bool SkipCache) {
+    ModuleMap::KnownHeader *SuggestedModule, bool *IsMapped, bool SkipCache) {
   Module *RequestingModule = getModuleForLocation(FilenameLoc);
   bool RequestingModuleIsModuleInterface = !SourceMgr.isInMainFile(FilenameLoc);
 
@@ -819,7 +814,7 @@ const FileEntry *Preprocessor::LookupFile(
     while (const FileEntry *FE = HeaderInfo.LookupFile(
                Filename, FilenameLoc, isAngled, TmpFromDir, TmpCurDir,
                Includers, SearchPath, RelativePath, RequestingModule,
-               SuggestedModule, SkipCache)) {
+               SuggestedModule, /*IsMapped=*/nullptr, SkipCache)) {
       // Keep looking as if this file did a #include_next.
       TmpFromDir = TmpCurDir;
       ++TmpFromDir;
@@ -835,7 +830,7 @@ const FileEntry *Preprocessor::LookupFile(
   // Do a standard file entry lookup.
   const FileEntry *FE = HeaderInfo.LookupFile(
       Filename, FilenameLoc, isAngled, FromDir, CurDir, Includers, SearchPath,
-      RelativePath, RequestingModule, SuggestedModule, SkipCache,
+      RelativePath, RequestingModule, SuggestedModule, IsMapped, SkipCache,
       BuildSystemModule);
   if (FE) {
     if (SuggestedModule && !LangOpts.AsmPreprocessor)
@@ -1593,18 +1588,18 @@ bool Preprocessor::ConcatenateIncludeName(SmallString<128> &FilenameBuffer,
 }
 
 /// \brief Push a token onto the token stream containing an annotation.
-static void EnterAnnotationToken(Preprocessor &PP,
-                                 SourceLocation Begin, SourceLocation End,
-                                 tok::TokenKind Kind, void *AnnotationVal) {
+void Preprocessor::EnterAnnotationToken(SourceRange Range,
+                                        tok::TokenKind Kind,
+                                        void *AnnotationVal) {
   // FIXME: Produce this as the current token directly, rather than
   // allocating a new token for it.
   auto Tok = llvm::make_unique<Token[]>(1);
   Tok[0].startToken();
   Tok[0].setKind(Kind);
-  Tok[0].setLocation(Begin);
-  Tok[0].setAnnotationEndLoc(End);
+  Tok[0].setLocation(Range.getBegin());
+  Tok[0].setAnnotationEndLoc(Range.getEnd());
   Tok[0].setAnnotationValue(AnnotationVal);
-  PP.EnterTokenStream(std::move(Tok), 1, true);
+  EnterTokenStream(std::move(Tok), 1, true);
 }
 
 /// \brief Produce a diagnostic informing the user that a #include or similar
@@ -1783,6 +1778,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
   }
 
   // Search include directories.
+  bool IsMapped = false;
   const DirectoryLookup *CurDir;
   SmallString<1024> SearchPath;
   SmallString<1024> RelativePath;
@@ -1801,7 +1797,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
       FilenameLoc, LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename,
       isAngled, LookupFrom, LookupFromFile, CurDir,
       Callbacks ? &SearchPath : nullptr, Callbacks ? &RelativePath : nullptr,
-      &SuggestedModule);
+      &SuggestedModule, &IsMapped);
 
   if (!File) {
     if (Callbacks) {
@@ -1818,7 +1814,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
               FilenameLoc,
               LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, isAngled,
               LookupFrom, LookupFromFile, CurDir, nullptr, nullptr,
-              &SuggestedModule, /*SkipCache*/ true);
+              &SuggestedModule, &IsMapped, /*SkipCache*/ true);
         }
       }
     }
@@ -1833,8 +1829,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
             LangOpts.MSVCCompat ? NormalizedPath.c_str() : Filename, false,
             LookupFrom, LookupFromFile, CurDir,
             Callbacks ? &SearchPath : nullptr,
-            Callbacks ? &RelativePath : nullptr,
-            &SuggestedModule);
+            Callbacks ? &RelativePath : nullptr, &SuggestedModule, &IsMapped);
         if (File) {
           SourceRange Range(FilenameTok.getLocation(), CharEnd);
           Diag(FilenameTok, diag::err_pp_file_not_found_not_fatal) <<
@@ -1964,7 +1959,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
   // Issue a diagnostic if the name of the file on disk has a different case
   // than the one we're about to open.
   const bool CheckIncludePathPortability =
-    File && !File->tryGetRealPathName().empty();
+      !IsMapped && File && !File->tryGetRealPathName().empty();
 
   if (CheckIncludePathPortability) {
     StringRef Name = LangOpts.MSVCCompat ? NormalizedPath.str() : Filename;
@@ -2026,7 +2021,8 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
 
       if (IncludeTok.getIdentifierInfo()->getPPKeywordID() !=
           tok::pp___include_macros)
-        EnterAnnotationToken(*this, HashLoc, End, tok::annot_module_include, M);
+        EnterAnnotationToken(SourceRange(HashLoc, End),
+                             tok::annot_module_include, M);
     }
     return;
   }
@@ -2064,7 +2060,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
     // submodule.
     // FIXME: There's no point doing this if we're handling a #__include_macros
     // directive.
-    EnterAnnotationToken(*this, HashLoc, End, tok::annot_module_begin, M);
+    EnterAnnotationToken(SourceRange(HashLoc, End), tok::annot_module_begin, M);
   }
 }
 
@@ -2592,25 +2588,26 @@ void Preprocessor::HandleUndefDirective() {
   // Okay, we have a valid identifier to undef.
   auto *II = MacroNameTok.getIdentifierInfo();
   auto MD = getMacroDefinition(II);
+  UndefMacroDirective *Undef = nullptr;
+  
+  // If the macro is not defined, this is a noop undef.
+  if (const MacroInfo *MI = MD.getMacroInfo()) {
+    if (!MI->isUsed() && MI->isWarnIfUnused())
+      Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used);
+
+    if (MI->isWarnIfUnused())
+      WarnUnusedMacroLocs.erase(MI->getDefinitionLoc());
+
+    Undef = AllocateUndefMacroDirective(MacroNameTok.getLocation());
+  }
 
   // If the callbacks want to know, tell them about the macro #undef.
   // Note: no matter if the macro was defined or not.
   if (Callbacks)
-    Callbacks->MacroUndefined(MacroNameTok, MD);
-
-  // If the macro is not defined, this is a noop undef, just return.
-  const MacroInfo *MI = MD.getMacroInfo();
-  if (!MI)
-    return;
-
-  if (!MI->isUsed() && MI->isWarnIfUnused())
-    Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used);
-
-  if (MI->isWarnIfUnused())
-    WarnUnusedMacroLocs.erase(MI->getDefinitionLoc());
+    Callbacks->MacroUndefined(MacroNameTok, MD, Undef);
 
-  appendMacroDirective(MacroNameTok.getIdentifierInfo(),
-                       AllocateUndefMacroDirective(MacroNameTok.getLocation()));
+  if (Undef)
+    appendMacroDirective(II, Undef);
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/lib/Lex/PPLexerChange.cpp b/lib/Lex/PPLexerChange.cpp
index cf0c953b61f8..fcc49b387034 100644
--- a/lib/Lex/PPLexerChange.cpp
+++ b/lib/Lex/PPLexerChange.cpp
@@ -287,6 +287,48 @@ const char *Preprocessor::getCurLexerEndPos() {
   return EndPos;
 }
 
+static void collectAllSubModulesWithUmbrellaHeader(
+    const Module &Mod, SmallVectorImpl<const Module *> &SubMods) {
+  if (Mod.getUmbrellaHeader())
+    SubMods.push_back(&Mod);
+  for (auto *M : Mod.submodules())
+    collectAllSubModulesWithUmbrellaHeader(*M, SubMods);
+}
+
+void Preprocessor::diagnoseMissingHeaderInUmbrellaDir(const Module &Mod) {
+  assert(Mod.getUmbrellaHeader() && "Module must use umbrella header");
+  SourceLocation StartLoc =
+      SourceMgr.getLocForStartOfFile(SourceMgr.getMainFileID());
+  if (getDiagnostics().isIgnored(diag::warn_uncovered_module_header, StartLoc))
+    return;
+
+  ModuleMap &ModMap = getHeaderSearchInfo().getModuleMap();
+  const DirectoryEntry *Dir = Mod.getUmbrellaDir().Entry;
+  vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+  std::error_code EC;
+  for (vfs::recursive_directory_iterator Entry(FS, Dir->getName(), EC), End;
+       Entry != End && !EC; Entry.increment(EC)) {
+    using llvm::StringSwitch;
+
+    // Check whether this entry has an extension typically associated with
+    // headers.
+    if (!StringSwitch<bool>(llvm::sys::path::extension(Entry->getName()))
+             .Cases(".h", ".H", ".hh", ".hpp", true)
+             .Default(false))
+      continue;
+
+    if (const FileEntry *Header = getFileManager().getFile(Entry->getName()))
+      if (!getSourceManager().hasFileInfo(Header)) {
+        if (!ModMap.isHeaderInUnavailableModule(Header)) {
+          // Find the relative path that would access this header.
+          SmallString<128> RelativePath;
+          computeRelativePath(FileMgr, Dir, Header, RelativePath);
+          Diag(StartLoc, diag::warn_uncovered_module_header)
+              << Mod.getFullModuleName() << RelativePath;
+        }
+      }
+  }
+}
 
 /// HandleEndOfFile - This callback is invoked when the lexer hits the end of
 /// the current file.  This either returns the EOF token or pops a level off
@@ -473,44 +515,14 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
   }
 
   // If we are building a module that has an umbrella header, make sure that
-  // each of the headers within the directory covered by the umbrella header
-  // was actually included by the umbrella header.
+  // each of the headers within the directory, including all submodules, is
+  // covered by the umbrella header was actually included by the umbrella
+  // header.
   if (Module *Mod = getCurrentModule()) {
-    if (Mod->getUmbrellaHeader()) {
-      SourceLocation StartLoc
-        = SourceMgr.getLocForStartOfFile(SourceMgr.getMainFileID());
-
-      if (!getDiagnostics().isIgnored(diag::warn_uncovered_module_header,
-                                      StartLoc)) {
-        ModuleMap &ModMap = getHeaderSearchInfo().getModuleMap();
-        const DirectoryEntry *Dir = Mod->getUmbrellaDir().Entry;
-        vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
-        std::error_code EC;
-        for (vfs::recursive_directory_iterator Entry(FS, Dir->getName(), EC), End;
-             Entry != End && !EC; Entry.increment(EC)) {
-          using llvm::StringSwitch;
-          
-          // Check whether this entry has an extension typically associated with
-          // headers.
-          if (!StringSwitch<bool>(llvm::sys::path::extension(Entry->getName()))
-                 .Cases(".h", ".H", ".hh", ".hpp", true)
-                 .Default(false))
-            continue;
-
-          if (const FileEntry *Header =
-                  getFileManager().getFile(Entry->getName()))
-            if (!getSourceManager().hasFileInfo(Header)) {
-              if (!ModMap.isHeaderInUnavailableModule(Header)) {
-                // Find the relative path that would access this header.
-                SmallString<128> RelativePath;
-                computeRelativePath(FileMgr, Dir, Header, RelativePath);              
-                Diag(StartLoc, diag::warn_uncovered_module_header)
-                  << Mod->getFullModuleName() << RelativePath;
-              }
-            }
-        }
-      }
-    }
+    llvm::SmallVector<const Module *, 4> AllMods;
+    collectAllSubModulesWithUmbrellaHeader(*Mod, AllMods);
+    for (auto *M : AllMods)
+      diagnoseMissingHeaderInUmbrellaDir(*M);
   }
 
   return true;
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 358c96a78300..196223981d74 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -1422,7 +1422,7 @@ static bool EvaluateHasIncludeCommon(Token &Tok,
   const DirectoryLookup *CurDir;
   const FileEntry *File =
       PP.LookupFile(FilenameLoc, Filename, isAngled, LookupFrom, LookupFromFile,
-                    CurDir, nullptr, nullptr, nullptr);
+                    CurDir, nullptr, nullptr, nullptr, nullptr);
 
   // Get the result value.  A result of true means the file exists.
   return File != nullptr;
diff --git a/lib/Lex/Pragma.cpp b/lib/Lex/Pragma.cpp
index 87e105d1d03d..576151a98b2c 100644
--- a/lib/Lex/Pragma.cpp
+++ b/lib/Lex/Pragma.cpp
@@ -508,7 +508,7 @@ void Preprocessor::HandlePragmaDependency(Token &DependencyTok) {
   const DirectoryLookup *CurDir;
   const FileEntry *File =
       LookupFile(FilenameTok.getLocation(), Filename, isAngled, nullptr,
-                 nullptr, CurDir, nullptr, nullptr, nullptr);
+                 nullptr, CurDir, nullptr, nullptr, nullptr, nullptr);
   if (!File) {
     if (!SuppressIncludeNotFoundError)
       Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
@@ -534,6 +534,47 @@ void Preprocessor::HandlePragmaDependency(Token &DependencyTok) {
   }
 }
 
+void Preprocessor::HandlePragmaModuleImport(Token &ImportTok) {
+  SourceLocation ImportLoc = ImportTok.getLocation();
+
+  Token Tok;
+
+  llvm::SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 8> ModuleName;
+  while (true) {
+    LexUnexpandedToken(Tok);
+    if (Tok.isNot(tok::identifier)) {
+      Diag(Tok.getLocation(),
+           diag::err_pragma_module_import_expected_module_name) << 0;
+      return;
+    }
+
+    ModuleName.emplace_back(Tok.getIdentifierInfo(), Tok.getLocation());
+
+    LexUnexpandedToken(Tok);
+    assert(Tok.isNot(tok::eof));
+    if (Tok.is(tok::eod))
+      break;
+    if (Tok.isNot(tok::period)) {
+      Diag(Tok.getLocation(),
+           diag::err_pragma_module_import_expected_module_name) << 1;
+      return;
+    }
+  }
+
+  // If we have a non-empty module path, load the named module.
+  Module *Imported =
+      TheModuleLoader.loadModule(ImportLoc, ModuleName, Module::Hidden,
+                                 /*IsIncludeDirective=*/false);
+  if (!Imported)
+    return;
+
+  makeModuleVisible(Imported, ImportLoc);
+  EnterAnnotationToken(SourceRange(ImportLoc, Tok.getLocation()),
+                       tok::annot_module_include, Imported);
+  if (Callbacks)
+    Callbacks->moduleImport(ImportLoc, ModuleName, Imported);
+}
+
 /// ParsePragmaPushOrPopMacro - Handle parsing of pragma push_macro/pop_macro.
 /// Return the IdentifierInfo* associated with the macro to push or pop.
 IdentifierInfo *Preprocessor::ParsePragmaPushOrPopMacro(Token &Tok) {
@@ -1301,6 +1342,19 @@ public:
   }
 };
 
+/// Handle the clang \#pragma module import extension. The syntax is:
+/// \code
+///   #pragma clang module import some.module.name
+/// \endcode
+struct PragmaModuleImportHandler : public PragmaHandler {
+  PragmaModuleImportHandler() : PragmaHandler("import") {}
+
+  void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
+                    Token &ImportTok) override {
+    PP.HandlePragmaModuleImport(ImportTok);
+  }
+};
+
 /// PragmaPushMacroHandler - "\#pragma push_macro" saves the value of the
 /// macro on the top of the stack.
 struct PragmaPushMacroHandler : public PragmaHandler {
@@ -1524,6 +1578,11 @@ void Preprocessor::RegisterBuiltinPragmas() {
   AddPragmaHandler("clang", new PragmaARCCFCodeAuditedHandler());
   AddPragmaHandler("clang", new PragmaAssumeNonNullHandler());
 
+  // #pragma clang module ...
+  auto *ModuleHandler = new PragmaNamespace("module");
+  AddPragmaHandler("clang", ModuleHandler);
+  ModuleHandler->AddPragma(new PragmaModuleImportHandler());
+
   AddPragmaHandler("STDC", new PragmaSTDC_FENV_ACCESSHandler());
   AddPragmaHandler("STDC", new PragmaSTDC_CX_LIMITED_RANGEHandler());
   AddPragmaHandler("STDC", new PragmaSTDC_UnknownHandler());
diff --git a/lib/Lex/PreprocessingRecord.cpp b/lib/Lex/PreprocessingRecord.cpp
index 13e15f3c943b..03c4cbe589d5 100644
--- a/lib/Lex/PreprocessingRecord.cpp
+++ b/lib/Lex/PreprocessingRecord.cpp
@@ -422,7 +422,8 @@ void PreprocessingRecord::MacroDefined(const Token &Id,
 }
 
 void PreprocessingRecord::MacroUndefined(const Token &Id,
-                                         const MacroDefinition &MD) {
+                                         const MacroDefinition &MD,
+                                         const MacroDirective *Undef) {
   MD.forAllDefinitions([&](MacroInfo *MI) { MacroDefinitions.erase(MI); });
 }
 
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 044ec74679d5..b3ba86e0685b 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -9866,25 +9866,6 @@ void Sema::CheckBoolLikeConversion(Expr *E, SourceLocation CC) {
   ::CheckBoolLikeConversion(*this, E, CC);
 }
 
-/// Diagnose when expression is an integer constant expression and its evaluation
-/// results in integer overflow
-void Sema::CheckForIntOverflow (Expr *E) {
-  // Use a work list to deal with nested struct initializers.
-  SmallVector<Expr *, 2> Exprs(1, E);
-
-  do {
-    Expr *E = Exprs.pop_back_val();
-
-    if (isa<BinaryOperator>(E->IgnoreParenCasts())) {
-      E->IgnoreParenCasts()->EvaluateForOverflow(Context);
-      continue;
-    }
-
-    if (auto InitList = dyn_cast<InitListExpr>(E))
-      Exprs.append(InitList->inits().begin(), InitList->inits().end());
-  } while (!Exprs.empty());
-}
-
 namespace {
 /// \brief Visitor for expressions which looks for unsequenced operations on the
 /// same object.
@@ -10386,7 +10367,7 @@ void Sema::CheckCompletedExpr(Expr *E, SourceLocation CheckLoc,
   if (!E->isInstantiationDependent())
     CheckUnsequencedOperations(E);
   if (!IsConstexpr && !E->isValueDependent())
-    CheckForIntOverflow(E);
+    E->EvaluateForOverflow(Context);
   DiagnoseMisalignedMembers();
 }
 
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index f838c9a4877d..054ccb64cbec 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -2960,6 +2960,20 @@ bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
     RequiresAdjustment = true;
   }
 
+  if (OldTypeInfo.getNoCallerSavedRegs() !=
+      NewTypeInfo.getNoCallerSavedRegs()) {
+    if (NewTypeInfo.getNoCallerSavedRegs()) {
+      AnyX86NoCallerSavedRegistersAttr *Attr = 
+        New->getAttr<AnyX86NoCallerSavedRegistersAttr>();
+      Diag(New->getLocation(), diag::err_function_attribute_mismatch) << Attr;
+      Diag(OldLocation, diag::note_previous_declaration);
+      return true;
+    }
+
+    NewTypeInfo = NewTypeInfo.withNoCallerSavedRegs(true);
+    RequiresAdjustment = true;
+  }
+
   if (RequiresAdjustment) {
     const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
     AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
@@ -7410,6 +7424,10 @@ class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
 
 } // end anonymous namespace
 
+void Sema::MarkTypoCorrectedFunctionDefinition(const NamedDecl *F) {
+  TypoCorrectedFunctionDefinitions.insert(F);
+}
+
 /// \brief Generate diagnostics for an invalid function redeclaration.
 ///
 /// This routine handles generating the diagnostic messages for an invalid
@@ -7507,6 +7525,8 @@ static NamedDecl *DiagnoseInvalidRedeclaration(
         if ((*I)->getCanonicalDecl() == Canonical)
           Correction.setCorrectionDecl(*I);
 
+      // Let Sema know about the correction.
+      SemaRef.MarkTypoCorrectedFunctionDefinition(Result);
       SemaRef.diagnoseTypo(
           Correction,
           SemaRef.PDiag(IsLocalFriend
@@ -11718,6 +11738,11 @@ Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
   if (canRedefineFunction(Definition, getLangOpts()))
     return;
 
+  // Don't emit an error when this is redifinition of a typo-corrected
+  // definition.
+  if (TypoCorrectedFunctionDefinitions.count(Definition))
+    return;
+
   // If we don't have a visible definition of the function, and it's inline or
   // a template, skip the new definition.
   if (SkipBody && !hasVisibleDefinition(Definition) &&
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 17c6975ca5e9..bb5434a03a10 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -1941,17 +1941,26 @@ static void handleNakedAttr(Sema &S, Decl *D, const AttributeList &Attr) {
 static void handleNoReturnAttr(Sema &S, Decl *D, const AttributeList &attr) {
   if (hasDeclarator(D)) return;
 
-  if (S.CheckNoReturnAttr(attr)) return;
+  if (S.CheckNoReturnAttr(attr))
+    return;
 
   if (!isa<ObjCMethodDecl>(D)) {
     S.Diag(attr.getLoc(), diag::warn_attribute_wrong_decl_type)
-      << attr.getName() << ExpectedFunctionOrMethod;
+        << attr.getName() << ExpectedFunctionOrMethod;
     return;
   }
 
-  D->addAttr(::new (S.Context)
-             NoReturnAttr(attr.getRange(), S.Context,
-                          attr.getAttributeSpellingListIndex()));
+  D->addAttr(::new (S.Context) NoReturnAttr(
+      attr.getRange(), S.Context, attr.getAttributeSpellingListIndex()));
+}
+
+static void handleNoCallerSavedRegsAttr(Sema &S, Decl *D,
+                                        const AttributeList &Attr) {
+  if (S.CheckNoCallerSavedRegsAttr(Attr))
+    return;
+
+  D->addAttr(::new (S.Context) AnyX86NoCallerSavedRegistersAttr(
+      Attr.getRange(), S.Context, Attr.getAttributeSpellingListIndex()));
 }
 
 bool Sema::CheckNoReturnAttr(const AttributeList &attr) {
@@ -1963,6 +1972,22 @@ bool Sema::CheckNoReturnAttr(const AttributeList &attr) {
   return false;
 }
 
+bool Sema::CheckNoCallerSavedRegsAttr(const AttributeList &Attr) {
+  // Check whether the attribute is valid on the current target.
+  if (!Attr.existsInTarget(Context.getTargetInfo())) {
+    Diag(Attr.getLoc(), diag::warn_unknown_attribute_ignored) << Attr.getName();
+    Attr.setInvalid();
+    return true;
+  }
+
+  if (!checkAttributeNumArgs(*this, Attr, 0)) {
+    Attr.setInvalid();
+    return true;
+  }
+
+  return false;
+}
+
 static void handleAnalyzerNoReturnAttr(Sema &S, Decl *D,
                                        const AttributeList &Attr) {
   
@@ -6428,6 +6453,9 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
   case AttributeList::AT_TypeTagForDatatype:
     handleTypeTagForDatatypeAttr(S, D, Attr);
     break;
+  case AttributeList::AT_AnyX86NoCallerSavedRegisters:
+    handleNoCallerSavedRegsAttr(S, D, Attr);
+    break;
   case AttributeList::AT_RenderScriptKernel:
     handleSimpleAttribute<RenderScriptKernelAttr>(S, D, Attr);
     break;
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index 4f51cd399c0c..fe9ba6f1f811 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -4313,6 +4313,51 @@ static void mergeInterfaceMethodToImpl(Sema &S,
   }
 }
 
+/// Verify that the method parameters/return value have types that are supported
+/// by the x86 target.
+static void checkObjCMethodX86VectorTypes(Sema &SemaRef,
+                                          const ObjCMethodDecl *Method) {
+  assert(SemaRef.getASTContext().getTargetInfo().getTriple().getArch() ==
+             llvm::Triple::x86 &&
+         "x86-specific check invoked for a different target");
+  SourceLocation Loc;
+  QualType T;
+  for (const ParmVarDecl *P : Method->parameters()) {
+    if (P->getType()->isVectorType()) {
+      Loc = P->getLocStart();
+      T = P->getType();
+      break;
+    }
+  }
+  if (Loc.isInvalid()) {
+    if (Method->getReturnType()->isVectorType()) {
+      Loc = Method->getReturnTypeSourceRange().getBegin();
+      T = Method->getReturnType();
+    } else
+      return;
+  }
+
+  // Vector parameters/return values are not supported by objc_msgSend on x86 in
+  // iOS < 9 and macOS < 10.11.
+  const auto &Triple = SemaRef.getASTContext().getTargetInfo().getTriple();
+  VersionTuple AcceptedInVersion;
+  if (Triple.getOS() == llvm::Triple::IOS)
+    AcceptedInVersion = VersionTuple(/*Major=*/9);
+  else if (Triple.isMacOSX())
+    AcceptedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/11);
+  else
+    return;
+  VersionTuple MethodVersion = Method->getVersionIntroduced();
+  if (SemaRef.getASTContext().getTargetInfo().getPlatformMinVersion() >=
+          AcceptedInVersion &&
+      (MethodVersion.empty() || MethodVersion >= AcceptedInVersion))
+    return;
+  SemaRef.Diag(Loc, diag::err_objc_method_unsupported_param_ret_type)
+      << T << (Method->getReturnType()->isVectorType() ? /*return value*/ 1
+                                                       : /*parameter*/ 0)
+      << (Triple.isMacOSX() ? "macOS 10.11" : "iOS 9");
+}
+
 Decl *Sema::ActOnMethodDeclaration(
     Scope *S,
     SourceLocation MethodLoc, SourceLocation EndLoc,
@@ -4534,6 +4579,10 @@ Decl *Sema::ActOnMethodDeclaration(
       ObjCMethod->SetRelatedResultType();
   }
 
+  if (MethodDefinition &&
+      Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
+    checkObjCMethodX86VectorTypes(*this, ObjCMethod);
+
   ActOnDocumentableDecl(ObjCMethod);
 
   return ObjCMethod;
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 00480f821fc6..f7307f35568d 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -5275,8 +5275,7 @@ ExprResult Sema::ActOnCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
   if (Fn->getType() == Context.OverloadTy) {
     OverloadExpr::FindResult find = OverloadExpr::find(Fn);
 
-    // We aren't supposed to apply this logic for if there'Scope an '&'
-    // involved.
+    // We aren't supposed to apply this logic if there's an '&' involved.
     if (!find.HasFormOfMemberPointer) {
       OverloadExpr *ovl = find.Expression;
       if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(ovl))
@@ -6432,14 +6431,13 @@ static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS,
       return S.Context
           .getQualifiedType(CompositeTy.getUnqualifiedType(), CompositeQuals)
           .withCVRQualifiers(MergedCVRQual);
-    } else
-      return CompositeTy.withCVRQualifiers(MergedCVRQual);
+    }
+    return CompositeTy.withCVRQualifiers(MergedCVRQual);
   }();
   if (IsBlockPointer)
     ResultTy = S.Context.getBlockPointerType(ResultTy);
-  else {
+  else
     ResultTy = S.Context.getPointerType(ResultTy);
-  }
 
   LHS = S.ImpCastExprToType(LHS.get(), ResultTy, LHSCastKind);
   RHS = S.ImpCastExprToType(RHS.get(), ResultTy, RHSCastKind);
diff --git a/lib/Sema/SemaExprObjC.cpp b/lib/Sema/SemaExprObjC.cpp
index 9cc443ed4fd9..a44e9243e3c5 100644
--- a/lib/Sema/SemaExprObjC.cpp
+++ b/lib/Sema/SemaExprObjC.cpp
@@ -595,7 +595,6 @@ ExprResult Sema::BuildObjCBoxedExpr(SourceRange SR, Expr *ValueExpr) {
         break;
       }
     }
-    CheckForIntOverflow(ValueExpr);
     // FIXME:  Do I need to do anything special with BoolTy expressions?
     
     // Look for the appropriate method within NSNumber.
diff --git a/lib/Sema/SemaOpenMP.cpp b/lib/Sema/SemaOpenMP.cpp
index fb13669407fc..43fd055bbc56 100644
--- a/lib/Sema/SemaOpenMP.cpp
+++ b/lib/Sema/SemaOpenMP.cpp
@@ -824,21 +824,18 @@ DSAStackTy::hasDSA(ValueDecl *D,
   if (isStackEmpty())
     return {};
   D = getCanonicalDecl(D);
-  auto StartI = std::next(Stack.back().first.rbegin());
+  auto I = (FromParent && Stack.back().first.size() > 1)
+               ? std::next(Stack.back().first.rbegin())
+               : Stack.back().first.rbegin();
   auto EndI = Stack.back().first.rend();
-  if (FromParent && StartI != EndI)
-    StartI = std::next(StartI);
-  if (StartI == EndI)
-    return {};
-  auto I = std::prev(StartI);
-  do {
-    ++I;
+  while (std::distance(I, EndI) > 1) {
+    std::advance(I, 1);
     if (!DPred(I->Directive) && !isParallelOrTaskRegion(I->Directive))
       continue;
     DSAVarData DVar = getDSA(I, D);
     if (CPred(DVar.CKind))
       return DVar;
-  } while (I != EndI);
+  }
   return {};
 }
 
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 29ba34479dab..782c377e3202 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -11426,6 +11426,10 @@ static void AddOverloadedCallCandidate(Sema &S,
       assert(!KnownValid && "Explicit template arguments?");
       return;
     }
+    // Prevent ill-formed function decls to be added as overload candidates.
+    if (!dyn_cast<FunctionProtoType>(Func->getType()->getAs<FunctionType>()))
+      return;
+
     S.AddOverloadCandidate(Func, FoundDecl, Args, CandidateSet,
                            /*SuppressUsedConversions=*/false,
                            PartialOverloading);
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 279b9ecef94e..bcc66bbd1c0a 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -119,8 +119,9 @@ static void diagnoseBadTypeAttribute(Sema &S, const AttributeList &attr,
 
 // Function type attributes.
 #define FUNCTION_TYPE_ATTRS_CASELIST \
-    case AttributeList::AT_NoReturn: \
-    case AttributeList::AT_Regparm: \
+  case AttributeList::AT_NoReturn: \
+  case AttributeList::AT_Regparm: \
+  case AttributeList::AT_AnyX86NoCallerSavedRegisters: \
     CALLING_CONV_ATTRS_CASELIST
 
 // Microsoft-specific type qualifiers.
@@ -6371,6 +6372,20 @@ static bool handleFunctionTypeAttr(TypeProcessingState &state,
     return true;
   }
 
+  if (attr.getKind() == AttributeList::AT_AnyX86NoCallerSavedRegisters) {
+    if (S.CheckNoCallerSavedRegsAttr(attr))
+      return true;
+
+    // Delay if this is not a function type.
+    if (!unwrapped.isFunctionType())
+      return false;
+
+    FunctionType::ExtInfo EI =
+        unwrapped.get()->getExtInfo().withNoCallerSavedRegs(true);
+    type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
+    return true;
+  }
+
   if (attr.getKind() == AttributeList::AT_Regparm) {
     unsigned value;
     if (S.CheckRegparmAttr(attr, value))
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index 7b1edc062d1e..5312ad118d5b 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -3765,6 +3765,13 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
       SourceMgr.getLoadedSLocEntryByID(Index);
     }
 
+    // Map the original source file ID into the ID space of the current
+    // compilation.
+    if (F.OriginalSourceFileID.isValid()) {
+      F.OriginalSourceFileID = FileID::get(
+          F.SLocEntryBaseID + F.OriginalSourceFileID.getOpaqueValue() - 1);
+    }
+
     // Preload all the pending interesting identifiers by marking them out of
     // date.
     for (auto Offset : F.PreloadIdentifierOffsets) {
@@ -3873,10 +3880,6 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
 
   ModuleFile &PrimaryModule = ModuleMgr.getPrimaryModule();
   if (PrimaryModule.OriginalSourceFileID.isValid()) {
-    PrimaryModule.OriginalSourceFileID
-      = FileID::get(PrimaryModule.SLocEntryBaseID
-                    + PrimaryModule.OriginalSourceFileID.getOpaqueValue() - 1);
-
     // If this AST file is a precompiled preamble, then set the
     // preamble file ID of the source manager to the file source file
     // from which the preamble was built.
@@ -5575,6 +5578,13 @@ void ASTReader::ReadPragmaDiagnosticMappings(DiagnosticsEngine &Diag) {
       FirstState = ReadDiagState(
           F.isModule() ? DiagState() : *Diag.DiagStatesByLoc.CurDiagState,
           SourceLocation(), F.isModule());
+
+      // For an explicit module, set up the root buffer of the module to start
+      // with the initial diagnostic state of the module itself, to cover files
+      // that contain no explicit transitions.
+      if (F.isModule())
+        Diag.DiagStatesByLoc.Files[F.OriginalSourceFileID]
+            .StateTransitions.push_back({FirstState, 0});
     }
 
     // Read the state transitions.
@@ -5801,13 +5811,13 @@ QualType ASTReader::readTypeRecord(unsigned Index) {
   }
 
   case TYPE_FUNCTION_NO_PROTO: {
-    if (Record.size() != 6) {
+    if (Record.size() != 7) {
       Error("incorrect encoding of no-proto function type");
       return QualType();
     }
     QualType ResultType = readType(*Loc.F, Record, Idx);
     FunctionType::ExtInfo Info(Record[1], Record[2], Record[3],
-                               (CallingConv)Record[4], Record[5]);
+                               (CallingConv)Record[4], Record[5], Record[6]);
     return Context.getFunctionNoProtoType(ResultType, Info);
   }
 
@@ -5819,9 +5829,10 @@ QualType ASTReader::readTypeRecord(unsigned Index) {
                                         /*hasregparm*/ Record[2],
                                         /*regparm*/ Record[3],
                                         static_cast<CallingConv>(Record[4]),
-                                        /*produces*/ Record[5]);
+                                        /*produces*/ Record[5],
+                                        /*nocallersavedregs*/ Record[6]);
 
-    unsigned Idx = 6;
+    unsigned Idx = 7;
 
     EPI.Variadic = Record[Idx++];
     EPI.HasTrailingReturn = Record[Idx++];
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index 84d2420f4ba9..80bf65666ece 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -255,6 +255,7 @@ void ASTTypeWriter::VisitFunctionType(const FunctionType *T) {
   // FIXME: need to stabilize encoding of calling convention...
   Record.push_back(C.getCC());
   Record.push_back(C.getProducesResult());
+  Record.push_back(C.getNoCallerSavedRegs());
 
   if (C.getHasRegParm() || C.getRegParm() || C.getProducesResult())
     AbbrevToUse = 0;
@@ -839,6 +840,7 @@ void ASTWriter::WriteTypeAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(0));                         // RegParm
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // CC
   Abv->Add(BitCodeAbbrevOp(0));                         // ProducesResult
+  Abv->Add(BitCodeAbbrevOp(0));                         // NoCallerSavedRegs
   // FunctionProtoType
   Abv->Add(BitCodeAbbrevOp(0));                         // IsVariadic
   Abv->Add(BitCodeAbbrevOp(0));                         // HasTrailingReturn
diff --git a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 5730517289bb..9a7e83c14923 100644
--- a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -401,6 +401,9 @@ private:
   void ReportUseZeroAllocated(CheckerContext &C, SourceRange Range,
                               SymbolRef Sym) const;
 
+  void ReportFunctionPointerFree(CheckerContext &C, SVal ArgVal,
+                                 SourceRange Range, const Expr *FreeExpr) const;
+
   /// Find the location of the allocation for Sym on the path leading to the
   /// exploded node N.
   LeakInfo getAllocationSite(const ExplodedNode *N, SymbolRef Sym,
@@ -1564,6 +1567,11 @@ ProgramStateRef MallocChecker::FreeMemAux(CheckerContext &C,
     }
   }
 
+  if (SymBase->getType()->isFunctionPointerType()) {
+    ReportFunctionPointerFree(C, ArgVal, ArgExpr->getSourceRange(), ParentExpr);
+    return nullptr;
+  }
+
   ReleasedAllocated = (RsBase != nullptr) && (RsBase->isAllocated() ||
                                               RsBase->isAllocatedOfSizeZero());
 
@@ -2024,10 +2032,45 @@ void MallocChecker::ReportUseZeroAllocated(CheckerContext &C,
   }
 }
 
+void MallocChecker::ReportFunctionPointerFree(CheckerContext &C, SVal ArgVal,
+                                              SourceRange Range,
+                                              const Expr *FreeExpr) const {
+  if (!ChecksEnabled[CK_MallocChecker])
+    return;
+
+  Optional<MallocChecker::CheckKind> CheckKind = getCheckIfTracked(C, FreeExpr);
+  if (!CheckKind.hasValue())
+    return;
+
+  if (ExplodedNode *N = C.generateErrorNode()) {
+    if (!BT_BadFree[*CheckKind])
+      BT_BadFree[*CheckKind].reset(
+          new BugType(CheckNames[*CheckKind], "Bad free", "Memory Error"));
+
+    SmallString<100> Buf;
+    llvm::raw_svector_ostream Os(Buf);
+
+    const MemRegion *MR = ArgVal.getAsRegion();
+    while (const ElementRegion *ER = dyn_cast_or_null<ElementRegion>(MR))
+      MR = ER->getSuperRegion();
+
+    Os << "Argument to ";
+    if (!printAllocDeallocName(Os, C, FreeExpr))
+      Os << "deallocator";
+
+    Os << " is a function pointer";
+
+    auto R = llvm::make_unique<BugReport>(*BT_BadFree[*CheckKind], Os.str(), N);
+    R->markInteresting(MR);
+    R->addRange(Range);
+    C.emitReport(std::move(R));
+  }
+}
+
 ProgramStateRef MallocChecker::ReallocMemAux(CheckerContext &C,
                                              const CallExpr *CE,
                                              bool FreesOnFail,
-                                             ProgramStateRef State, 
+                                             ProgramStateRef State,
                                              bool SuffixWithN) const {
   if (!State)
     return nullptr;
diff --git a/lib/StaticAnalyzer/Frontend/ModelInjector.cpp b/lib/StaticAnalyzer/Frontend/ModelInjector.cpp
index c6f3baa7e3b2..cdb1ed9b3815 100644
--- a/lib/StaticAnalyzer/Frontend/ModelInjector.cpp
+++ b/lib/StaticAnalyzer/Frontend/ModelInjector.cpp
@@ -65,7 +65,7 @@ void ModelInjector::onBodySynthesis(const NamedDecl *D) {
   auto Invocation = std::make_shared<CompilerInvocation>(CI.getInvocation());
 
   FrontendOptions &FrontendOpts = Invocation->getFrontendOpts();
-  InputKind IK = IK_CXX; // FIXME
+  InputKind IK = InputKind::CXX; // FIXME
   FrontendOpts.Inputs.clear();
   FrontendOpts.Inputs.emplace_back(fileName, IK);
   FrontendOpts.DisableFree = true;
diff --git a/test/ARCMT/remap-applying.c b/test/ARCMT/remap-applying.c
new file mode 100644
index 000000000000..dee2e391d5bd
--- /dev/null
+++ b/test/ARCMT/remap-applying.c
@@ -0,0 +1,4 @@
+a bc
+
+// RUN: echo "[{\"file\": \"%/s\", \"offset\": 1, \"remove\": 2, }]" > %t.remap
+// RUN: c-arcmt-test %t.remap | arcmt-test -verify-transformed-files %s.result
diff --git a/test/ARCMT/remap-applying.c.result b/test/ARCMT/remap-applying.c.result
new file mode 100644
index 000000000000..514e9c264915
--- /dev/null
+++ b/test/ARCMT/remap-applying.c.result
@@ -0,0 +1,4 @@
+ac
+
+// RUN: echo "[{\"file\": \"%/s\", \"offset\": 1, \"remove\": 2, }]" > %t.remap
+// RUN: c-arcmt-test %t.remap | arcmt-test -verify-transformed-files %s.result
diff --git a/test/Analysis/malloc.c b/test/Analysis/malloc.c
index d5f2cfedd185..4c364ebd9a2f 100644
--- a/test/Analysis/malloc.c
+++ b/test/Analysis/malloc.c
@@ -1774,6 +1774,16 @@ int testNoCheckerDataPropogationFromLogicalOpOperandToOpResult(void) {
    return ok; // no warning
 }
 
+void (*fnptr)(int);
+void freeIndirectFunctionPtr() {
+  void *p = (void *)fnptr;
+  free(p); // expected-warning {{Argument to free() is a function pointer}}
+}
+
+void freeFunctionPtr() {
+  free((void *)fnptr); // expected-warning {{Argument to free() is a function pointer}}
+}
+
 // ----------------------------------------------------------------------------
 // False negatives.
 
diff --git a/test/CodeGen/atomic-ops-libcall.c b/test/CodeGen/atomic-ops-libcall.c
index 0093a8cbbbba..c673b07f8ed8 100644
--- a/test/CodeGen/atomic-ops-libcall.c
+++ b/test/CodeGen/atomic-ops-libcall.c
@@ -1,5 +1,8 @@
 // RUN: %clang_cc1 < %s -triple armv5e-none-linux-gnueabi -emit-llvm -O1 | FileCheck %s
 
+// FIXME: This file should not be checking -O1 output.
+// Ie, it is testing many IR optimizer passes as part of front-end verification.
+
 enum memory_order {
   memory_order_relaxed, memory_order_consume, memory_order_acquire,
   memory_order_release, memory_order_acq_rel, memory_order_seq_cst
@@ -110,7 +113,8 @@ int test_atomic_xor_fetch(int *p) {
 int test_atomic_nand_fetch(int *p) {
   // CHECK: test_atomic_nand_fetch
   // CHECK: [[CALL:%[^ ]*]] = tail call i32 @__atomic_fetch_nand_4(i8* {{%[0-9]+}}, i32 55, i32 5)
-  // CHECK: [[OR:%[^ ]*]] = or i32 [[CALL]], -56
-  // CHECK: {{%[^ ]*}} = xor i32 [[OR]], 55
+  // FIXME: We should not be checking optimized IR. It changes independently of clang.
+  // FIXME-CHECK: [[AND:%[^ ]*]] = and i32 [[CALL]], 55
+  // FIXME-CHECK: {{%[^ ]*}} = xor i32 [[AND]], -1
   return __atomic_nand_fetch(p, 55, memory_order_seq_cst);
 }
diff --git a/test/CodeGen/avx-builtins.c b/test/CodeGen/avx-builtins.c
index 483266408179..90f428efb339 100644
--- a/test/CodeGen/avx-builtins.c
+++ b/test/CodeGen/avx-builtins.c
@@ -1386,6 +1386,27 @@ void test_mm256_zeroupper() {
   return _mm256_zeroupper();
 }
 
+__m256d test_mm256_zextpd128_pd256(__m128d A) {
+  // CHECK-LABEL: test_mm256_zextpd128_pd256
+  // CHECK: store <2 x double> zeroinitializer
+  // CHECK: shufflevector <2 x double> %{{.*}}, <2 x double> %{{.*}}, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
+  return _mm256_zextpd128_pd256(A);
+}
+
+__m256 test_mm256_zextps128_ps256(__m128 A) {
+  // CHECK-LABEL: test_mm256_zextps128_ps256
+  // CHECK: store <4 x float> zeroinitializer
+  // CHECK: shufflevector <4 x float> %{{.*}}, <4 x float> %{{.*}}, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
+  return _mm256_zextps128_ps256(A);
+}
+
+__m256i test_mm256_zextsi128_si256(__m128i A) {
+  // CHECK-LABEL: test_mm256_zextsi128_si256
+  // CHECK: store <2 x i64> zeroinitializer
+  // CHECK: shufflevector <2 x i64> %{{.*}}, <2 x i64> %{{.*}}, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
+  return _mm256_zextsi128_si256(A);
+}
+
 double test_mm256_cvtsd_f64(__m256d __a)
 {
  // CHECK-LABEL: @test_mm256_cvtsd_f64
diff --git a/test/CodeGen/avx512f-builtins.c b/test/CodeGen/avx512f-builtins.c
index 3ae80141b3b9..c66d83611ed1 100644
--- a/test/CodeGen/avx512f-builtins.c
+++ b/test/CodeGen/avx512f-builtins.c
@@ -8387,3 +8387,44 @@ __m512 test_mm512_mask_abs_ps(__m512 __W, __mmask16 __U, __m512 __A){
   return _mm512_mask_abs_ps( __W, __U, __A);
 }
 
+__m512d test_mm512_zextpd128_pd512(__m128d A) {
+  // CHECK-LABEL: test_mm512_zextpd128_pd512
+  // CHECK: store <2 x double> zeroinitializer
+  // CHECK: shufflevector <2 x double> %{{.*}}, <2 x double> %{{.*}}, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 2, i32 3, i32 2, i32 3>
+  return _mm512_zextpd128_pd512(A);
+}
+
+__m512d test_mm512_zextpd256_pd512(__m256d A) {
+  // CHECK-LABEL: test_mm512_zextpd256_pd512
+  // CHECK: store <4 x double> zeroinitializer
+  // CHECK: shufflevector <4 x double> %{{.*}}, <4 x double> %{{.*}}, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
+  return _mm512_zextpd256_pd512(A);
+}
+
+__m512 test_mm512_zextps128_ps512(__m128 A) {
+  // CHECK-LABEL: test_mm512_zextps128_ps512
+  // CHECK: store <4 x float> zeroinitializer
+  // CHECK: shufflevector <4 x float> %{{.*}}, <4 x float> %{{.*}}, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 4, i32 5, i32 6, i32 7, i32 4, i32 5, i32 6, i32 7>
+  return _mm512_zextps128_ps512(A);
+}
+
+__m512 test_mm512_zextps256_ps512(__m256 A) {
+  // CHECK-LABEL: test_mm512_zextps256_ps512
+  // CHECK: store <8 x float> zeroinitializer
+  // CHECK: shufflevector <8 x float> %{{.*}}, <8 x float> %{{.*}}, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
+  return _mm512_zextps256_ps512(A);
+}
+
+__m512i test_mm512_zextsi128_si512(__m128i A) {
+  // CHECK-LABEL: test_mm512_zextsi128_si512
+  // CHECK: store <2 x i64> zeroinitializer
+  // CHECK: shufflevector <2 x i64> %{{.*}}, <2 x i64> %{{.*}}, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 2, i32 3, i32 2, i32 3>
+  return _mm512_zextsi128_si512(A);
+}
+
+__m512i test_mm512_zextsi256_si512(__m256i A) {
+  // CHECK-LABEL: test_mm512_zextsi256_si512
+  // CHECK: store <4 x i64> zeroinitializer
+  // CHECK: shufflevector <4 x i64> %{{.*}}, <4 x i64> %{{.*}}, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
+  return _mm512_zextsi256_si512(A);
+}
diff --git a/test/CodeGen/sse2-builtins.c b/test/CodeGen/sse2-builtins.c
index a140a6ce55b5..ca51314d80b8 100644
--- a/test/CodeGen/sse2-builtins.c
+++ b/test/CodeGen/sse2-builtins.c
@@ -951,6 +951,13 @@ __m128d test_mm_set_pd(double A, double B) {
   return _mm_set_pd(A, B);
 }
 
+__m128d test_mm_set_pd1(double A) {
+  // CHECK-LABEL: test_mm_set_pd1
+  // CHECK: insertelement <2 x double> undef, double %{{.*}}, i32 0
+  // CHECK: insertelement <2 x double> %{{.*}}, double %{{.*}}, i32 1
+  return _mm_set_pd1(A);
+}
+
 __m128d test_mm_set_sd(double A) {
   // CHECK-LABEL: test_mm_set_sd
   // CHECK: insertelement <2 x double> undef, double %{{.*}}, i32 0
diff --git a/test/CodeGenCXX/attr-x86-no_caller_saved_registers.cpp b/test/CodeGenCXX/attr-x86-no_caller_saved_registers.cpp
new file mode 100644
index 000000000000..f583f16eb569
--- /dev/null
+++ b/test/CodeGenCXX/attr-x86-no_caller_saved_registers.cpp
@@ -0,0 +1,31 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu %s -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-win32 %s -emit-llvm -o - | FileCheck %s
+
+// CHECK: foo{{[^#]*}}#[[ATTRS:[0-9]+]]
+__attribute__((no_caller_saved_registers)) void foo() {}
+namespace S {
+// CHECK: bar{{[^#]*}}#[[ATTRS]]
+__attribute__((no_caller_saved_registers)) void bar(int *a) { foo(); }
+}
+
+struct St {
+  static void baz(int *a) __attribute__((no_caller_saved_registers)) { S::bar(a); }
+};
+
+__attribute((no_caller_saved_registers)) void (*foobar)(void);
+
+// CHECK-LABEL: @main
+int main(int argc, char **argv) {
+  St::baz(&argc);
+  // CHECK: [[FOOBAR:%.+]] = load void ()*, void ()** @{{.*}}foobar{{.*}},
+  // CHECK-NEXT: call void [[FOOBAR]]() #[[ATTRS1:.+]]
+  foobar();
+  return 0;
+}
+
+// CHECK: baz{{[^#]*}}#[[ATTRS]]
+
+// CHECK: attributes #[[ATTRS]] = {
+// CHECK-SAME: "no_caller_saved_registers"
+// CHECK-SAME: }
+// CHECK: attributes #[[ATTRS1]] = { "no_caller_saved_registers" }
diff --git a/test/CodeGenCXX/debug-info-namespace.cpp b/test/CodeGenCXX/debug-info-namespace.cpp
index c75c40766a37..5b81197671e2 100644
--- a/test/CodeGenCXX/debug-info-namespace.cpp
+++ b/test/CodeGenCXX/debug-info-namespace.cpp
@@ -53,24 +53,30 @@ inline namespace I {
 int var_i;
 }
 }
-void B::func_fwd() {}
+namespace {
+int anonymous;
+}
+void B::func_fwd() {
+  anonymous = 0;
+}
+
 
 // This should work even if 'i' and 'func' were declarations & not definitions,
 // but it doesn't yet.
 
 // CHECK: [[I:![0-9]+]] = distinct !DIGlobalVariable(name: "i",{{.*}} scope: [[NS:![0-9]+]],
-// CHECK: [[NS]] = !DINamespace(name: "B", scope: [[CTXT:![0-9]+]], file: [[FOOCPP:![0-9]+]], line: 1)
-// CHECK: [[FOOCPP]] = !DIFile(filename: "foo.cpp"
-// CHECK: [[CTXT]] = !DINamespace(name: "A", scope: null, file: [[FILE:![0-9]+]], line: 5)
-// CHECK: [[FILE]] = !DIFile(filename: "{{.*}}debug-info-namespace.cpp",
+// CHECK: [[NS]] = !DINamespace(name: "B", scope: [[CTXT:![0-9]+]])
+// CHECK: [[CTXT]] = !DINamespace(name: "A", scope: null)
+// CHECK: [[FOOCPP:.*]] = !DIFile(filename: "foo.cpp"
 // CHECK: [[VAR_FWD:![0-9]+]] = distinct !DIGlobalVariable(name: "var_fwd",{{.*}} scope: [[NS]],
 // CHECK-SAME:                                             line: 44
 // CHECK-SAME:                                             isDefinition: true
 // CHECK: distinct !DIGlobalVariable(name: "var_i",{{.*}} scope: [[INLINE:![0-9]+]],
-// CHECK: [[INLINE]] = !DINamespace(name: "I", scope: [[CTXT]], file: [[FOOCPP]], line: 46, exportSymbols: true)
+// CHECK: [[INLINE]] = !DINamespace(name: "I", scope: [[CTXT]], exportSymbols: true)
+// CHECK: !DINamespace(scope: null)
 // CHECK: [[CU:![0-9]+]] = distinct !DICompileUnit(
 // CHECK-SAME:                            imports: [[MODULES:![0-9]*]]
-// CHECK: [[MODULES]] = !{[[M1:![0-9]+]], [[M2:![0-9]+]], [[M3:![0-9]+]], [[M4:![0-9]+]], [[M5:![0-9]+]], [[M6:![0-9]+]], [[M7:![0-9]+]], [[M8:![0-9]+]], [[M9:![0-9]+]], [[M10:![0-9]+]], [[M11:![0-9]+]], [[M12:![0-9]+]], [[M13:![0-9]+]], [[M14:![0-9]+]], [[M15:![0-9]+]], [[M16:![0-9]+]], [[M17:![0-9]+]]}
+// CHECK: [[MODULES]] = !{[[M1:![0-9]+]], [[M2:![0-9]+]], [[M3:![0-9]+]], [[M4:![0-9]+]], [[M5:![0-9]+]], [[M6:![0-9]+]], [[M7:![0-9]+]], [[M8:![0-9]+]], [[M9:![0-9]+]], [[M10:![0-9]+]], [[M11:![0-9]+]], [[M12:![0-9]+]], [[M13:![0-9]+]], [[M14:![0-9]+]], [[M15:![0-9]+]], [[M16:![0-9]+]], [[M17:![0-9]+]]
 // CHECK: [[M1]] = !DIImportedEntity(tag: DW_TAG_imported_module, scope: [[CTXT]], entity: [[NS]], line: 15)
 
 // CHECK: [[M2]] = !DIImportedEntity(tag: DW_TAG_imported_module, scope: [[CU]], entity: [[CTXT]],
@@ -106,7 +112,7 @@ void B::func_fwd() {}
 // CHECK-SAME:                          scope: [[NS]], file: [[FOOCPP]], line: 9
 // CHECK: [[M15]] = !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: [[FUNC]], entity: [[VAR_FWD:![0-9]+]]
 // CHECK: [[M16]] = !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: [[FUNC]], entity: [[FUNC_FWD:![0-9]+]]
-// CHECK: [[FUNC_FWD]] = distinct !DISubprogram(name: "func_fwd",{{.*}} line: 50,{{.*}} isDefinition: true
+// CHECK: [[FUNC_FWD]] = distinct !DISubprogram(name: "func_fwd",{{.*}} line: 53,{{.*}} isDefinition: true
 // CHECK: [[M17]] = !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: [[CTXT]], entity: [[I]]
 
 // CHECK-GMLT: [[CU:![0-9]+]] = distinct !DICompileUnit(
diff --git a/test/CodeGenCXX/ubsan-nullability-assign.cpp b/test/CodeGenCXX/ubsan-nullability-assign.cpp
new file mode 100644
index 000000000000..3f85c88d6e76
--- /dev/null
+++ b/test/CodeGenCXX/ubsan-nullability-assign.cpp
@@ -0,0 +1,35 @@
+// RUN: %clang_cc1 -x c++ -triple x86_64-apple-darwin10 -emit-llvm -o - %s -fsanitize=nullability-assign | FileCheck %s
+
+struct S1 {
+  int *_Nonnull p;
+};
+
+struct S2 {
+  S1 s1;
+};
+
+union U1 {
+  S1 s1;
+  S2 s2;
+};
+
+// CHECK-LABEL: define void @{{.*}}f1
+void f1(int *p) {
+  U1 u;
+
+  // CHECK: [[ICMP:%.*]] = icmp ne i32* {{.*}}, null, !nosanitize
+  // CHECK-NEXT: br i1 [[ICMP]], {{.*}}, !nosanitize
+  // CHECK: call void @__ubsan_handle_type_mismatch{{.*}} !nosanitize
+  // CHECK: store
+  u.s1.p = p;
+
+  // CHECK: [[ICMP:%.*]] = icmp ne i32* {{.*}}, null, !nosanitize
+  // CHECK-NEXT: br i1 [[ICMP]], {{.*}}, !nosanitize
+  // CHECK: call void @__ubsan_handle_type_mismatch{{.*}} !nosanitize
+  // CHECK: store
+  u.s2.s1.p = p;
+
+  // CHECK-NOT: __ubsan_handle_type_mismatch
+  // CHECK-NOT: store
+  // CHECK: ret void
+}
diff --git a/test/CodeGenObjC/arc-blocks.m b/test/CodeGenObjC/arc-blocks.m
index 4bb618c3a415..69cd7bb297b2 100644
--- a/test/CodeGenObjC/arc-blocks.m
+++ b/test/CodeGenObjC/arc-blocks.m
@@ -298,15 +298,11 @@ void test7(void) {
 // CHECK:      [[D0:%.*]] = getelementptr inbounds [[BLOCK_T]], [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
 // CHECK:      [[T0:%.*]] = getelementptr inbounds [[BLOCK_T]], [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
 // CHECK-NEXT: [[T1:%.*]] = load [[TEST8]]*, [[TEST8]]** [[SELF]],
-// CHECK-NEXT: [[T2:%.*]] = bitcast [[TEST8]]* [[T1]] to i8*
-// CHECK-NEXT: [[T3:%.*]] = call i8* @objc_retain(i8* [[T2]])
-// CHECK-NEXT: [[T4:%.*]] = bitcast i8* [[T3]] to [[TEST8]]*
-// CHECK-NEXT: store [[TEST8]]* [[T4]], [[TEST8]]** [[T0]]
+// CHECK-NEXT: store %0* [[T1]], %0** [[T0]]
 // CHECK-NEXT: bitcast [[BLOCK_T]]* [[BLOCK]] to
 // CHECK: call void @test8_helper(
-// CHECK-NEXT: [[T1:%.*]] = load [[TEST8]]*, [[TEST8]]** [[D0]]
-// CHECK-NEXT: [[T2:%.*]] = bitcast [[TEST8]]* [[T1]] to i8*
-// CHECK-NEXT: call void @objc_release(i8* [[T2]])
+// CHECK-NEXT: [[T2:%.*]] = load [[TEST8]]*, [[TEST8]]** [[D0]]
+// CHECK-NEXT: call void (...) @clang.arc.use([[TEST8]]* [[T2]])
 // CHECK: ret void
 
   extern void test8_helper(void (^)(void));
@@ -741,5 +737,31 @@ void test19(void (^b)(void)) {
 // CHECK-NEXT: ret void
 }
 
+// CHECK-LABEL: define void @test20(
+// CHECK: [[XADDR:%.*]] = alloca i8*
+// CHECK-NEXT: [[BLOCK:%.*]] = alloca <[[BLOCKTY:.*]]>
+// CHECK-NEXT: [[RETAINEDX:%.*]] = call i8* @objc_retain(i8* %{{.*}})
+// CHECK-NEXT: store i8* [[RETAINEDX]], i8** [[XADDR]]
+// CHECK-NEXT: [[CAPTUREFIELD:%.*]] = getelementptr inbounds <[[BLOCKTY]]>, <[[BLOCKTY]]>* [[BLOCK]], i32 0, i32 5
+// CHECK: [[BLOCKCAPTURED:%.*]] = getelementptr inbounds <[[BLOCKTY]]>, <[[BLOCKTY]]>* [[BLOCK]], i32 0, i32 5
+// CHECK: [[CAPTURED:%.*]] = load i8*, i8** [[XADDR]]
+// CHECK: store i8* [[CAPTURED]], i8** [[BLOCKCAPTURED]]
+// CHECK: [[CAPTURE:%.*]] = load i8*, i8** [[CAPTUREFIELD]]
+// CHECK-NEXT: call void (...) @clang.arc.use(i8* [[CAPTURE]])
+// CHECK-NEXT: [[X:%.*]] = load i8*, i8** [[XADDR]]
+// CHECK-NEXT: call void @objc_release(i8* [[X]])
+// CHECK-NEXT: ret void
+
+// CHECK-LABEL: define internal void @__copy_helper_block
+// CHECK: [[BLOCKSOURCE:%.*]] = bitcast i8* %{{.*}} to <[[BLOCKTY]]>*
+// CHECK: [[CAPTUREFIELD:%.*]] = getelementptr inbounds <[[BLOCKTY]]>, <[[BLOCKTY]]>* [[BLOCKSOURCE]], i32 0, i32 5
+// CHECK: [[BLOCKCOPYSRC:%.*]] = load i8*, i8** [[CAPTUREFIELD]]
+// CHECK: call i8* @objc_retain(i8* [[BLOCKCOPYSRC]])
+
+void test20_callee(void (^)());
+void test20(const id x) {
+  test20_callee(^{ (void)x; });
+}
+
 // CHECK: attributes [[NUW]] = { nounwind }
 // CHECK-UNOPT: attributes [[NUW]] = { nounwind }
diff --git a/test/CodeGenObjC/arc-foreach.m b/test/CodeGenObjC/arc-foreach.m
index db150e88a59f..e34445704e37 100644
--- a/test/CodeGenObjC/arc-foreach.m
+++ b/test/CodeGenObjC/arc-foreach.m
@@ -63,11 +63,11 @@ void test0(NSArray *array) {
 // CHECK-LP64:      [[D0:%.*]] = getelementptr inbounds [[BLOCK_T]], [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
 // CHECK-LP64:      [[T0:%.*]] = getelementptr inbounds [[BLOCK_T]], [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
 // CHECK-LP64-NEXT: [[T1:%.*]] = load i8*, i8** [[X]]
-// CHECK-LP64-NEXT: [[T2:%.*]] = call i8* @objc_retain(i8* [[T1]])
-// CHECK-LP64-NEXT: store i8* [[T2]], i8** [[T0]]
-// CHECK-LP64-NEXT: [[T1:%.*]] = bitcast [[BLOCK_T]]* [[BLOCK]] 
-// CHECK-LP64: call void @use_block(
-// CHECK-LP64-NEXT: call void @objc_storeStrong(i8** [[D0]], i8* null)
+// CHECK-LP64-NEXT: store i8* [[T1]], i8** [[T0]]
+// CHECK-LP64-NEXT: [[BLOCK1:%.*]] = bitcast [[BLOCK_T]]* [[BLOCK]]
+// CHECK-LP64-NEXT: call void @use_block(void ()* [[BLOCK1]])
+// CHECK-LP64-NEXT: [[CAPTURE:%.*]] = load i8*, i8** [[D0]]
+// CHECK-LP64: call void (...) @clang.arc.use(i8* [[CAPTURE]])
 
 // CHECK-LP64:      [[T0:%.*]] = load i8*, i8** @OBJC_SELECTOR_REFERENCES_
 // CHECK-LP64-NEXT: [[T1:%.*]] = bitcast [[ARRAY_T]]* [[SAVED_ARRAY]] to i8*
@@ -200,13 +200,10 @@ NSArray *array4;
 // CHECK-LP64:         [[T0:%.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, [[TY]]* }>, <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, [[TY]]* }>* [[BLOCK]], i32 0, i32 5
 // CHECK-LP64:         [[BC:%.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, [[TY]]* }>, <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, [[TY]]* }>* [[BLOCK]], i32 0, i32 5
 // CHECK-LP64:         [[T1:%.*]] = load [[TY]]*, [[TY]]** [[SELF_ADDR]]
-// CHECK-LP64:         [[T2:%.*]] = bitcast [[TY]]* [[T1]] to i8*
-// CHECK-LP64:         [[T3:%.*]] = call i8* @objc_retain(i8* [[T2]])
-// CHECK-LP64:         [[T4:%.*]] = bitcast i8* [[T3]] to [[TY]]*
-// CHECK-LP64:         store [[TY]]* [[T4]], [[TY]]** [[BC]]
+// CHECK-LP64:         store [[TY]]* [[T1]], [[TY]]** [[BC]]
 
-// CHECK-LP64:         [[T5:%.*]] = bitcast [[TY]]** [[T0]] to i8**
-// CHECK-LP64:         call void @objc_storeStrong(i8** [[T5]], i8* null)
+// CHECK-LP64:         [[T5:%.*]] = load [[TY]]*, [[TY]]** [[T0]]
+// CHECK-LP64:         call void (...) @clang.arc.use([[TY]]* [[T5]])
 // CHECK-LP64:         switch i32 {{%.*}}, label %[[UNREACHABLE:.*]] [
 // CHECK-LP64-NEXT:      i32 0, label %[[CLEANUP_CONT:.*]]
 // CHECK-LP64-NEXT:      i32 2, label %[[FORCOLL_END:.*]]
diff --git a/test/CodeGenObjC/ubsan-nullability.m b/test/CodeGenObjC/ubsan-nullability.m
index 457f07136349..7f53ea6292ee 100644
--- a/test/CodeGenObjC/ubsan-nullability.m
+++ b/test/CodeGenObjC/ubsan-nullability.m
@@ -1,19 +1,22 @@
 // REQUIRES: asserts
 // RUN: %clang_cc1 -x objective-c -emit-llvm -triple x86_64-apple-macosx10.10.0 -fsanitize=nullability-arg,nullability-assign,nullability-return -w %s -o - | FileCheck %s
+// RUN: %clang_cc1 -x objective-c++ -emit-llvm -triple x86_64-apple-macosx10.10.0 -fsanitize=nullability-arg,nullability-assign,nullability-return -w %s -o - | FileCheck %s
 
 // CHECK: [[NONNULL_RV_LOC1:@.*]] = private unnamed_addr global {{.*}} i32 109, i32 1 {{.*}} i32 100, i32 6
 // CHECK: [[NONNULL_ARG_LOC:@.*]] = private unnamed_addr global {{.*}} i32 204, i32 15 {{.*}} i32 190, i32 23
 // CHECK: [[NONNULL_ASSIGN1_LOC:@.*]] = private unnamed_addr global {{.*}} i32 305, i32 9
 // CHECK: [[NONNULL_ASSIGN2_LOC:@.*]] = private unnamed_addr global {{.*}} i32 405, i32 10
-// CHECK: [[NONNULL_ASSIGN3_LOC:@.*]] = private unnamed_addr global {{.*}} i32 505, i32 10
+// CHECK: [[NONNULL_ASSIGN3_LOC:@.*]] = private unnamed_addr global {{.*}} i32 506, i32 10
 // CHECK: [[NONNULL_INIT1_LOC:@.*]] = private unnamed_addr global {{.*}} i32 604, i32 25
 // CHECK: [[NONNULL_INIT2_LOC1:@.*]] = private unnamed_addr global {{.*}} i32 707, i32 26
 // CHECK: [[NONNULL_INIT2_LOC2:@.*]] = private unnamed_addr global {{.*}} i32 707, i32 29
 // CHECK: [[NONNULL_RV_LOC2:@.*]] = private unnamed_addr global {{.*}} i32 817, i32 1 {{.*}} i32 800, i32 6
 
 #define NULL ((void *)0)
+#define INULL ((int *)NULL)
+#define INNULL ((int *_Nonnull)NULL)
 
-// CHECK-LABEL: define i32* @nonnull_retval1
+// CHECK-LABEL: define i32* @{{.*}}nonnull_retval1
 #line 100
 int *_Nonnull nonnull_retval1(int *p) {
   // CHECK: br i1 true, label %[[NULL:.*]], label %[[NONULL:.*]], !nosanitize
@@ -29,7 +32,7 @@ int *_Nonnull nonnull_retval1(int *p) {
 #line 190
 void nonnull_arg(int *_Nonnull p) {}
 
-// CHECK-LABEL: define void @call_func_with_nonnull_arg
+// CHECK-LABEL: define void @{{.*}}call_func_with_nonnull_arg
 #line 200
 void call_func_with_nonnull_arg(int *_Nonnull p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* {{.*}}, null, !nosanitize
@@ -38,7 +41,7 @@ void call_func_with_nonnull_arg(int *_Nonnull p) {
   nonnull_arg(p);
 }
 
-// CHECK-LABEL: define void @nonnull_assign1
+// CHECK-LABEL: define void @{{.*}}nonnull_assign1
 #line 300
 void nonnull_assign1(int *p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* {{.*}}, null, !nosanitize
@@ -48,7 +51,7 @@ void nonnull_assign1(int *p) {
   local = p;
 }
 
-// CHECK-LABEL: define void @nonnull_assign2
+// CHECK-LABEL: define void @{{.*}}nonnull_assign2
 #line 400
 void nonnull_assign2(int *p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* %{{.*}}, null, !nosanitize
@@ -62,17 +65,18 @@ struct S1 {
   int *_Nonnull mptr;
 };
 
-// CHECK-LABEL: define void @nonnull_assign3
+// CHECK-LABEL: define void @{{.*}}nonnull_assign3
 #line 500
 void nonnull_assign3(int *p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* %{{.*}}, null, !nosanitize
   // CHECK-NEXT: br i1 [[ICMP]], {{.*}}, !nosanitize
   // CHECK: call void @__ubsan_handle_type_mismatch{{.*}}[[NONNULL_ASSIGN3_LOC]]
+  // CHECK-NOT: call void @__ubsan_handle_type_mismatch
   struct S1 s;
   s.mptr = p;
 }
 
-// CHECK-LABEL: define void @nonnull_init1
+// CHECK-LABEL: define void @{{.*}}nonnull_init1
 #line 600
 void nonnull_init1(int *p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* %{{.*}}, null, !nosanitize
@@ -81,7 +85,7 @@ void nonnull_init1(int *p) {
   int *_Nonnull local = p;
 }
 
-// CHECK-LABEL: define void @nonnull_init2
+// CHECK-LABEL: define void @{{.*}}nonnull_init2
 #line 700
 void nonnull_init2(int *p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* %{{.*}}, null, !nosanitize
@@ -93,7 +97,7 @@ void nonnull_init2(int *p) {
   int *_Nonnull arr[] = {p, p};
 }
 
-// CHECK-LABEL: define i32* @nonnull_retval2
+// CHECK-LABEL: define i32* @{{.*}}nonnull_retval2
 #line 800
 int *_Nonnull nonnull_retval2(int *_Nonnull arg1,  //< Test this.
                               int *_Nonnull arg2,  //< Test this.
@@ -150,7 +154,7 @@ int *_Nonnull nonnull_retval2(int *_Nonnull arg1,  //< Test this.
 }
 @end
 
-// CHECK-LABEL: define void @call_A
+// CHECK-LABEL: define void @{{.*}}call_A
 void call_A(A *a, int *p) {
   // CHECK: [[ICMP:%.*]] = icmp ne i32* [[P1:%.*]], null, !nosanitize
   // CHECK-NEXT: br i1 [[ICMP]], {{.*}}, !nosanitize
@@ -168,15 +172,15 @@ void call_A(A *a, int *p) {
 void dont_crash(int *_Nonnull p, ...) {}
 
 int main() {
-  nonnull_retval1(NULL);
-  nonnull_retval2(NULL, NULL, NULL, NULL, 0, 0, 0, 0);
-  call_func_with_nonnull_arg(NULL);
-  nonnull_assign1(NULL);
-  nonnull_assign2(NULL);
-  nonnull_assign3(NULL);
-  nonnull_init1(NULL);
-  nonnull_init2(NULL);
-  call_A(NULL, NULL);
-  dont_crash(NULL, NULL);
+  nonnull_retval1(INULL);
+  nonnull_retval2(INNULL, INNULL, INULL, (int *_Nullable)NULL, 0, 0, 0, 0);
+  call_func_with_nonnull_arg(INNULL);
+  nonnull_assign1(INULL);
+  nonnull_assign2(INULL);
+  nonnull_assign3(INULL);
+  nonnull_init1(INULL);
+  nonnull_init2(INULL);
+  call_A((A *)NULL, INULL);
+  dont_crash(INNULL, NULL);
   return 0;
 }
diff --git a/test/CodeGenObjCXX/boxing.mm b/test/CodeGenObjCXX/boxing.mm
new file mode 100644
index 000000000000..dc353603581f
--- /dev/null
+++ b/test/CodeGenObjCXX/boxing.mm
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s | FileCheck %s
+
+@interface NSNumber
++ (id)numberWithInt:(int)n;
+@end
+
+int n = 1;
+int m = (@(n++), 0);
+
+// CHECK: define {{.*}} @__cxx_global_var_init()
+// CHECK: load i32, i32* @n
+// CHECK: store i32 %{{.*}}, i32* @n
diff --git a/test/Driver/cl-options.c b/test/Driver/cl-options.c
index ddfb3cbdc4ac..870378a8299d 100644
--- a/test/Driver/cl-options.c
+++ b/test/Driver/cl-options.c
@@ -14,6 +14,9 @@
 // C_P: "-E"
 // C_P: "-C"
 
+// RUN: %clang_cl /d1reportAllClassLayout -### -- %s 2>&1 | FileCheck -check-prefix=d1reportAllClassLayout %s
+// d1reportAllClassLayout: -fdump-record-layouts
+
 // RUN: %clang_cl /Dfoo=bar /D bar=baz /DMYDEF#value /DMYDEF2=foo#bar /DMYDEF3#a=b /DMYDEF4# \
 // RUN:    -### -- %s 2>&1 | FileCheck -check-prefix=D %s
 // D: "-D" "foo=bar"
diff --git a/test/Driver/split-debug.c b/test/Driver/split-debug.c
index c12164b4e2f1..52f53d3e712e 100644
--- a/test/Driver/split-debug.c
+++ b/test/Driver/split-debug.c
@@ -40,6 +40,13 @@
 // CHECK-GMLT-WITH-SPLIT: "-debug-info-kind=line-tables-only"
 // CHECK-GMLT-WITH-SPLIT: "-split-dwarf-file"
 
+// RUN: %clang -target x86_64-unknown-linux-gnu -g -fno-split-dwarf-inlining -S -### %s 2> %t
+// RUN: FileCheck -check-prefix=CHECK-NOINLINE-WITHOUT-SPLIT < %t %s
+//
+// CHECK-NOINLINE-WITHOUT-SPLIT-NOT: "-enable-split-dwarf"
+// CHECK-NOINLINE-WITHOUT-SPLIT: "-fno-split-dwarf-inlining"
+// CHECK-NOINLINE-WITHOUT-SPLIT: "-debug-info-kind=limited"
+
 // RUN: %clang -target x86_64-unknown-linux-gnu -gmlt -gsplit-dwarf -fno-split-dwarf-inlining -S -### %s 2> %t
 // RUN: FileCheck -check-prefix=CHECK-SPLIT-WITH-GMLT < %t %s
 //
diff --git a/test/Driver/unknown-std.c b/test/Driver/unknown-std.c
index ba3035fd4564..41736ec4887e 100644
--- a/test/Driver/unknown-std.c
+++ b/test/Driver/unknown-std.c
@@ -2,32 +2,18 @@
 // When user selects invalid language standard
 // print out supported values with short description.
 
-// RUN: not %clang %s -std=foobar -c 2>&1 | \
-// RUN: FileCheck --match-full-lines %s
+// RUN: not %clang %s -std=foobar -c 2>&1 | FileCheck --match-full-lines %s
+// RUN: not %clang -x objective-c %s -std=foobar -c 2>&1 | FileCheck --match-full-lines %s
+// RUN: not %clang -x renderscript %s -std=foobar -c 2>&1 | FileCheck --match-full-lines %s
 
 // CHECK: error: invalid value 'foobar' in '-std=foobar'
-// CHECK-NEXT: note: use 'c89' for 'ISO C 1990' standard
-// CHECK-NEXT: note: use 'c90' for 'ISO C 1990' standard
-// CHECK-NEXT: note: use 'iso9899:1990' for 'ISO C 1990' standard
+// CHECK-NEXT: note: use 'c89', 'c90', or 'iso9899:1990' for 'ISO C 1990' standard
 // CHECK-NEXT: note: use 'iso9899:199409' for 'ISO C 1990 with amendment 1' standard
-// CHECK-NEXT: note: use 'gnu89' for 'ISO C 1990 with GNU extensions' standard
-// CHECK-NEXT: note: use 'gnu90' for 'ISO C 1990 with GNU extensions' standard
-// CHECK-NEXT: note: use 'c99' for 'ISO C 1999' standard
-// CHECK-NEXT: note: use 'c9x' for 'ISO C 1999' standard
-// CHECK-NEXT: note: use 'iso9899:1999' for 'ISO C 1999' standard
-// CHECK-NEXT: note: use 'iso9899:199x' for 'ISO C 1999' standard
+// CHECK-NEXT: note: use 'gnu89' or 'gnu90' for 'ISO C 1990 with GNU extensions' standard
+// CHECK-NEXT: note: use 'c99' or 'iso9899:1999' for 'ISO C 1999' standard
 // CHECK-NEXT: note: use 'gnu99' for 'ISO C 1999 with GNU extensions' standard
-// CHECK-NEXT: note: use 'gnu9x' for 'ISO C 1999 with GNU extensions' standard
-// CHECK-NEXT: note: use 'c11' for 'ISO C 2011' standard
-// CHECK-NEXT: note: use 'c1x' for 'ISO C 2011' standard
-// CHECK-NEXT: note: use 'iso9899:2011' for 'ISO C 2011' standard
-// CHECK-NEXT: note: use 'iso9899:201x' for 'ISO C 2011' standard
+// CHECK-NEXT: note: use 'c11' or 'iso9899:2011' for 'ISO C 2011' standard
 // CHECK-NEXT: note: use 'gnu11' for 'ISO C 2011 with GNU extensions' standard
-// CHECK-NEXT: note: use 'gnu1x' for 'ISO C 2011 with GNU extensions' standard
-// CHECK-NEXT: note: use 'cl' for 'OpenCL 1.0' standard
-// CHECK-NEXT: note: use 'cl1.1' for 'OpenCL 1.1' standard
-// CHECK-NEXT: note: use 'cl1.2' for 'OpenCL 1.2' standard
-// CHECK-NEXT: note: use 'cl2.0' for 'OpenCL 2.0' standard
 
 // Make sure that no other output is present.
 // CHECK-NOT: {{^.+$}}
diff --git a/test/Driver/unknown-std.cl b/test/Driver/unknown-std.cl
index b87a8c881ce5..71c478afca88 100644
--- a/test/Driver/unknown-std.cl
+++ b/test/Driver/unknown-std.cl
@@ -6,7 +6,7 @@
 // RUN: FileCheck --match-full-lines %s
 
 // CHECK: error: invalid value 'foobar' in '-std=foobar'
-// CHECK-NEXT: note: use 'cl' for 'OpenCL 1.0' standard
+// CHECK-NEXT: note: use 'cl1.0' for 'OpenCL 1.0' standard
 // CHECK-NEXT: note: use 'cl1.1' for 'OpenCL 1.1' standard
 // CHECK-NEXT: note: use 'cl1.2' for 'OpenCL 1.2' standard
 // CHECK-NEXT: note: use 'cl2.0' for 'OpenCL 2.0' standard
diff --git a/test/Driver/unknown-std.cpp b/test/Driver/unknown-std.cpp
index faeb2cba8a4b..4f7a5e64a6ed 100644
--- a/test/Driver/unknown-std.cpp
+++ b/test/Driver/unknown-std.cpp
@@ -2,24 +2,20 @@
 // When user selects invalid language standard
 // print out supported values with short description.
 
-// RUN: not %clang %s -std=foobar -c 2>&1 | \
-// RUN: FileCheck --match-full-lines %s
+// RUN: not %clang %s -std=foobar -c 2>&1 | FileCheck --match-full-lines %s
+// RUN: not %clang -x objective-c++ %s -std=foobar -c 2>&1 | FileCheck --match-full-lines %s
+// RUN: not %clang -x cuda -nocudainc -nocudalib %s -std=foobar -c 2>&1 | FileCheck --match-full-lines --check-prefix=CHECK --check-prefix=CUDA %s
 
 // CHECK: error: invalid value 'foobar' in '-std=foobar'
-// CHECK-NEXT: note: use 'c++98' for 'ISO C++ 1998 with amendments' standard
-// CHECK-NEXT: note: use 'c++03' for 'ISO C++ 1998 with amendments' standard
-// CHECK-NEXT: note: use 'gnu++98' for 'ISO C++ 1998 with amendments and GNU extensions' standard
-// CHECK-NEXT: note: use 'c++0x' for 'ISO C++ 2011 with amendments' standard
+// CHECK-NEXT: note: use 'c++98' or 'c++03' for 'ISO C++ 1998 with amendments' standard
+// CHECK-NEXT: note: use 'gnu++98' or 'gnu++03' for 'ISO C++ 1998 with amendments and GNU extensions' standard
 // CHECK-NEXT: note: use 'c++11' for 'ISO C++ 2011 with amendments' standard
-// CHECK-NEXT: note: use 'gnu++0x' for 'ISO C++ 2011 with amendments and GNU extensions' standard
 // CHECK-NEXT: note: use 'gnu++11' for 'ISO C++ 2011 with amendments and GNU extensions' standard
-// CHECK-NEXT: note: use 'c++1y' for 'ISO C++ 2014 with amendments' standard
 // CHECK-NEXT: note: use 'c++14' for 'ISO C++ 2014 with amendments' standard
-// CHECK-NEXT: note: use 'gnu++1y' for 'ISO C++ 2014 with amendments and GNU extensions' standard
 // CHECK-NEXT: note: use 'gnu++14' for 'ISO C++ 2014 with amendments and GNU extensions' standard
 // CHECK-NEXT: note: use 'c++1z' for 'Working draft for ISO C++ 2017' standard
 // CHECK-NEXT: note: use 'gnu++1z' for 'Working draft for ISO C++ 2017 with GNU extensions' standard
-// CHECK-NEXT: note: use 'cuda' for 'NVIDIA CUDA(tm)' standard
+// CUDA-NEXT: note: use 'cuda' for 'NVIDIA CUDA(tm)' standard
 
 // Make sure that no other output is present.
 // CHECK-NOT: {{^.+$}}
diff --git a/test/Frontend/Inputs/empty.h b/test/Frontend/Inputs/empty.h
new file mode 100644
index 000000000000..e69de29bb2d1
--- /dev/null
+++ b/test/Frontend/Inputs/empty.h
diff --git a/test/Frontend/gnu-inline.c b/test/Frontend/gnu-inline.c
index 0272df7e71ec..75d4fe6516f1 100644
--- a/test/Frontend/gnu-inline.c
+++ b/test/Frontend/gnu-inline.c
@@ -3,8 +3,10 @@
 // RUN: %clang_cc1 -std=c99 -fgnu89-inline -fsyntax-only -x c -E -dM %s | FileCheck --check-prefix=GNU-INLINE %s
 // RUN: %clang_cc1 -fsyntax-only -x c++ -E -dM %s | FileCheck --check-prefix=GNU-INLINE %s
 // RUN: not %clang_cc1 -fgnu89-inline -fsyntax-only -x c++ %s 2>&1 | FileCheck --check-prefix=CXX %s
+// RUN: not %clang_cc1 -fgnu89-inline -fsyntax-only -x objective-c++ %s 2>&1 | FileCheck --check-prefix=OBJCXX %s
 
-// CXX: '-fgnu89-inline' not allowed with 'C++/ObjC++'
+// CXX: '-fgnu89-inline' not allowed with 'C++'
+// OBJCXX: '-fgnu89-inline' not allowed with 'Objective-C++'
 
 // STDC-INLINE-NOT: __GNUC_GNU_INLINE__
 // STDC-INLINE: #define __GNUC_STDC_INLINE__ 1
diff --git a/test/Frontend/rewrite-includes-line-markers.c b/test/Frontend/rewrite-includes-line-markers.c
index 14692a19e9bc..f5fb627fec16 100644
--- a/test/Frontend/rewrite-includes-line-markers.c
+++ b/test/Frontend/rewrite-includes-line-markers.c
@@ -3,6 +3,8 @@
 #include "test.h"
 int f() { return x; }
 
+#include "empty.h"
+
 // GNU: {{^}}# 1 "{{.*}}rewrite-includes-line-markers.c"
 // GNU: {{^}}#include "test.h"
 // GNU: {{^}}# 1 "{{.*}}test.h"
@@ -11,6 +13,9 @@ int f() { return x; }
 // GNU: {{^}}int x;
 // GNU: {{^}}# 4 "{{.*}}rewrite-includes-line-markers.c" 2
 // GNU: {{^}}int f() { return x; }
+// GNU: {{^}}
+// GNU: {{^}}# 1 "{{.*}}empty.h" 1
+// GNU: {{^}}# 7 "{{.*}}rewrite-includes-line-markers.c" 2
 
 // LINE: {{^}}#line 1 "{{.*}}rewrite-includes-line-markers.c"
 // LINE: {{^}}#include "test.h"
@@ -20,3 +25,6 @@ int f() { return x; }
 // LINE: {{^}}int x;
 // LINE: {{^}}#line 4 "{{.*}}rewrite-includes-line-markers.c"
 // LINE: {{^}}int f() { return x; }
+// LINE: {{^}}
+// LINE: {{^}}#line 1 "{{.*}}empty.h"
+// LINE: {{^}}#line 7 "{{.*}}rewrite-includes-line-markers.c"
diff --git a/test/Frontend/rewrite-includes-modules.c b/test/Frontend/rewrite-includes-modules.c
index 613609dfce24..e70fe0dbaf03 100644
--- a/test/Frontend/rewrite-includes-modules.c
+++ b/test/Frontend/rewrite-includes-modules.c
@@ -1,22 +1,27 @@
 // RUN: rm -rf %t
-// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -x objective-c %s -F %S/../Modules/Inputs -E -frewrite-includes -o - | FileCheck %s
+// RUN: mkdir %t
+// RUN: echo 'extern int dummy;' > %t/dummy.h
+// RUN: echo 'module dummy { header "dummy.h" }' > %t/module.modulemap
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t %s -I%t -E -frewrite-includes -o - | FileCheck %s
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -x objective-c %s -I%t -E -frewrite-includes -o - | FileCheck %s
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -x c++ %s -I%t -E -frewrite-includes -o - | FileCheck %s
 
 int bar();
-#include <Module/Module.h>
+#include "dummy.h"
 int foo();
-#include <Module/Module.h>
+#include "dummy.h"
 
 // CHECK: int bar();{{$}}
 // CHECK-NEXT: #if 0 /* expanded by -frewrite-includes */{{$}}
-// CHECK-NEXT: #include <Module/Module.h>{{$}}
+// CHECK-NEXT: #include "dummy.h"{{$}}
 // CHECK-NEXT: #endif /* expanded by -frewrite-includes */{{$}}
-// CHECK-NEXT: # 5 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
-// CHECK-NEXT: @import Module; /* clang -frewrite-includes: implicit import */{{$}}
-// CHECK-NEXT: # 6 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
+// CHECK-NEXT: # 10 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
+// CHECK-NEXT: #pragma clang module import dummy /* clang -frewrite-includes: implicit import */{{$}}
+// CHECK-NEXT: # 11 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
 // CHECK-NEXT: int foo();{{$}}
 // CHECK-NEXT: #if 0 /* expanded by -frewrite-includes */{{$}}
-// CHECK-NEXT: #include <Module/Module.h>{{$}}
+// CHECK-NEXT: #include "dummy.h"{{$}}
 // CHECK-NEXT: #endif /* expanded by -frewrite-includes */{{$}}
-// CHECK-NEXT: # 7 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
-// CHECK-NEXT: @import Module; /* clang -frewrite-includes: implicit import */{{$}}
-// CHECK-NEXT: # 8 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
+// CHECK-NEXT: # 12 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
+// CHECK-NEXT: #pragma clang module import dummy /* clang -frewrite-includes: implicit import */{{$}}
+// CHECK-NEXT: # 13 "{{.*[/\\]}}rewrite-includes-modules.c"{{$}}
diff --git a/test/Headers/stdint-typeof-MINMAX.cpp b/test/Headers/stdint-typeof-MINMAX.cpp
new file mode 100644
index 000000000000..7014259c59f9
--- /dev/null
+++ b/test/Headers/stdint-typeof-MINMAX.cpp
@@ -0,0 +1,32 @@
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=aarch64-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=arm-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=i386-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=mips-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=mips64-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=msp430-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=powerpc64-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=powerpc64-none-netbsd
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=powerpc-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=s390x-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=sparc-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=tce-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=x86_64-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=x86_64-pc-linux-gnu
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=i386-mingw32
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only -triple=xcore-none-none
+// RUN: %clang_cc1 %s -ffreestanding -std=c++1z -fsyntax-only
+
+#include <stdint.h>
+#include <stddef.h>
+
+static_assert(__is_same(__typeof__(INTPTR_MIN), intptr_t));
+static_assert(__is_same(__typeof__(INTPTR_MAX), intptr_t));
+static_assert(__is_same(__typeof__(UINTPTR_MAX), uintptr_t));
+static_assert(__is_same(__typeof__(PTRDIFF_MIN), ptrdiff_t));
+static_assert(__is_same(__typeof__(PTRDIFF_MAX), ptrdiff_t));
+static_assert(__is_same(__typeof__(SIZE_MAX), size_t));
+static_assert(__is_same(__typeof__(INTMAX_MIN), intmax_t));
+static_assert(__is_same(__typeof__(INTMAX_MAX), intmax_t));
+static_assert(__is_same(__typeof__(UINTMAX_MAX), uintmax_t));
+static_assert(__is_same(__typeof__(INTMAX_C(5)), intmax_t));
+static_assert(__is_same(__typeof__(UINTMAX_C(5)), uintmax_t));
diff --git a/test/Import/in-class-initializer/Inputs/S.cpp b/test/Import/in-class-initializer/Inputs/S.cpp
new file mode 100644
index 000000000000..28e631023540
--- /dev/null
+++ b/test/Import/in-class-initializer/Inputs/S.cpp
@@ -0,0 +1,3 @@
+struct S {
+  int a = 3;
+};
diff --git a/test/Import/in-class-initializer/test.cpp b/test/Import/in-class-initializer/test.cpp
new file mode 100644
index 000000000000..eaaac2ae5703
--- /dev/null
+++ b/test/Import/in-class-initializer/test.cpp
@@ -0,0 +1,5 @@
+// RUN: clang-import-test -import %S/Inputs/S.cpp -expression %s
+void expr() {
+  S MyS;
+  int b = MyS.a + MyS.a;
+}
diff --git a/test/Index/Core/index-source.m b/test/Index/Core/index-source.m
index a2eef89deea7..041753b95316 100644
--- a/test/Index/Core/index-source.m
+++ b/test/Index/Core/index-source.m
@@ -150,9 +150,9 @@ extern int setjmp(jmp_buf);
 // CHECK: [[@LINE+9]]:13 | instance-property/ObjC | prop | [[I2_prop_USR:.*]] | <no-cgname> | Def,RelChild,RelAcc | rel: 2
 // CHECK-NEXT: RelChild | I2 | [[I2_USR]]
 // CHECK-NEXT: RelAcc | _prop | c:objc(cs)I2@_prop
-// CHECK: [[@LINE+6]]:13 | instance-method/acc-get/ObjC | prop | [[I2_prop_getter_USR]] | -[I2 prop] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE+6]]:13 | instance-method/acc-get/ObjC | prop | [[I2_prop_getter_USR]] | -[I2 prop] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I2 | [[I2_USR]]
-// CHECK: [[@LINE+4]]:13 | instance-method/acc-set/ObjC | setProp: | [[I2_prop_setter_USR]] | -[I2 setProp:] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE+4]]:13 | instance-method/acc-set/ObjC | setProp: | [[I2_prop_setter_USR]] | -[I2 setProp:] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I2 | [[I2_USR]]
 // CHECK: [[@LINE+2]]:20 | field/ObjC | _prop | c:objc(cs)I2@_prop | <no-cgname> | Def,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I2 | [[I2_USR]]
@@ -214,8 +214,8 @@ extern int setjmp(jmp_buf);
 // CHECK: [[@LINE+5]]:13 | instance-property/ObjC | prop | c:objc(cs)I3(py)prop | <no-cgname> | Def,RelChild,RelAcc | rel: 2
 // CHECK-NEXT: RelChild | I3 | c:objc(cs)I3
 // CHECK-NEXT: RelAcc | _prop | c:objc(cs)I3@_prop
-// CHECK: [[@LINE+2]]:13 | instance-method/acc-get/ObjC | prop | c:objc(cs)I3(im)prop | -[I3 prop] | Def,Impl,RelChild | rel: 1
-// CHECK: [[@LINE+1]]:13 | instance-method/acc-set/ObjC | setProp: | c:objc(cs)I3(im)setProp: | -[I3 setProp:] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE+2]]:13 | instance-method/acc-get/ObjC | prop | c:objc(cs)I3(im)prop | -[I3 prop] | Def,Dyn,Impl,RelChild | rel: 1
+// CHECK: [[@LINE+1]]:13 | instance-method/acc-set/ObjC | setProp: | c:objc(cs)I3(im)setProp: | -[I3 setProp:] | Def,Dyn,Impl,RelChild | rel: 1
 @synthesize prop = _prop;
 @end
 
@@ -275,9 +275,9 @@ typedef MyGenCls<Base *><MyEnumerating> MyEnumerator;
 // CHECK: [[@LINE-1]]:13 | instance-property/ObjC | foo | c:objc(cs)I4(py)foo | <no-cgname> | Def,RelChild,RelAcc | rel: 2
 // CHECK-NEXT: RelChild | I4 | c:objc(cs)I4
 // CHECK-NEXT: RelAcc | _blahfoo | c:objc(cs)I4@_blahfoo
-// CHECK: [[@LINE-4]]:13 | instance-method/acc-get/ObjC | foo | c:objc(cs)I4(im)foo | -[I4 foo] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-4]]:13 | instance-method/acc-get/ObjC | foo | c:objc(cs)I4(im)foo | -[I4 foo] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I4 | c:objc(cs)I4
-// CHECK: [[@LINE-6]]:13 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I4(im)setFoo: | -[I4 setFoo:] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-6]]:13 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I4(im)setFoo: | -[I4 setFoo:] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I4 | c:objc(cs)I4
 // CHECK: [[@LINE-8]]:19 | field/ObjC | _blahfoo | c:objc(cs)I4@_blahfoo | <no-cgname> | Ref | rel: 0
 
@@ -296,9 +296,9 @@ typedef MyGenCls<Base *><MyEnumerating> MyEnumerator;
 // CHECK: [[@LINE-1]]:13 | instance-property/ObjC | foo | c:objc(cs)I5(py)foo | <no-cgname> | Def,RelChild,RelAcc | rel: 2
 // CHECK-NEXT: RelChild | I5 | c:objc(cs)I5
 // CHECK-NEXT: RelAcc | _blahfoo | c:objc(cs)I5@_blahfoo
-// CHECK: [[@LINE-4]]:13 | instance-method/acc-get/ObjC | foo | c:objc(cs)I5(im)foo | -[I5 foo] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-4]]:13 | instance-method/acc-get/ObjC | foo | c:objc(cs)I5(im)foo | -[I5 foo] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I5 | c:objc(cs)I5
-// CHECK: [[@LINE-6]]:13 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I5(im)setFoo: | -[I5 setFoo:] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-6]]:13 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I5(im)setFoo: | -[I5 setFoo:] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I5 | c:objc(cs)I5
 // CHECK: [[@LINE-8]]:19 | field/ObjC | _blahfoo | c:objc(cs)I5@_blahfoo | <no-cgname> | Def,RelChild | rel: 1
 
@@ -317,9 +317,9 @@ typedef MyGenCls<Base *><MyEnumerating> MyEnumerator;
 // CHECK: [[@LINE-1]]:13 | instance-property/ObjC | foo | c:objc(cs)I6(py)foo | <no-cgname> | Def,RelChild,RelAcc | rel: 2
 // CHECK-NEXT: RelChild | I6 | c:objc(cs)I6
 // CHECK-NEXT: RelAcc | foo | c:objc(cs)I6@foo
-// CHECK: [[@LINE-4]]:13 | instance-method/acc-get/ObjC | foo | c:objc(cs)I6(im)foo | -[I6 foo] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-4]]:13 | instance-method/acc-get/ObjC | foo | c:objc(cs)I6(im)foo | -[I6 foo] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I6 | c:objc(cs)I6
-// CHECK: [[@LINE-6]]:13 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I6(im)setFoo: | -[I6 setFoo:] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-6]]:13 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I6(im)setFoo: | -[I6 setFoo:] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I6 | c:objc(cs)I6
 // CHECK: [[@LINE-8]]:13 | field/ObjC | foo | c:objc(cs)I6@foo | <no-cgname> | Def,Impl,RelChild | rel: 1
 
@@ -337,9 +337,9 @@ typedef MyGenCls<Base *><MyEnumerating> MyEnumerator;
 // CHECK: [[@LINE-1]]:17 | instance-property/ObjC | foo | c:objc(cs)I7(py)foo | <no-cgname> | Def,Impl,RelChild,RelAcc | rel: 2
 // CHECK-NEXT: RelChild | I7 | c:objc(cs)I7
 // CHECK-NEXT: RelAcc | _foo | c:objc(cs)I7@_foo
-// CHECK: [[@LINE-4]]:17 | instance-method/acc-get/ObjC | foo | c:objc(cs)I7(im)foo | -[I7 foo] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-4]]:17 | instance-method/acc-get/ObjC | foo | c:objc(cs)I7(im)foo | -[I7 foo] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I7 | c:objc(cs)I7
-// CHECK: [[@LINE-6]]:17 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I7(im)setFoo: | -[I7 setFoo:] | Def,Impl,RelChild | rel: 1
+// CHECK: [[@LINE-6]]:17 | instance-method/acc-set/ObjC | setFoo: | c:objc(cs)I7(im)setFoo: | -[I7 setFoo:] | Def,Dyn,Impl,RelChild | rel: 1
 // CHECK-NEXT: RelChild | I7 | c:objc(cs)I7
 // CHECK: [[@LINE-8]]:17 | field/ObjC | _foo | c:objc(cs)I7@_foo | <no-cgname> | Def,Impl,RelChild | rel: 1
 
diff --git a/test/Index/allow-editor-placeholders.cpp b/test/Index/allow-editor-placeholders.cpp
new file mode 100644
index 000000000000..5a7207d3f07a
--- /dev/null
+++ b/test/Index/allow-editor-placeholders.cpp
@@ -0,0 +1,5 @@
+// RUN: c-index-test -test-load-source all %s 2>&1 | FileCheck %s
+
+<#placeholder#>;
+
+// CHECK-NOT: error
diff --git a/test/Index/cursor-dynamic-call.mm b/test/Index/cursor-dynamic-call.mm
index a926c3d03d47..33d1c68558f1 100644
--- a/test/Index/cursor-dynamic-call.mm
+++ b/test/Index/cursor-dynamic-call.mm
@@ -49,6 +49,14 @@ void test2() {
   id o = [[Test alloc] init];
 }
 
+@interface Test2 : NSObject
+@property (assign) id someProp;
+@end
+
+void test3(Test2 *o) {
+  id v = o.someProp;
+}
+
 // RUN: c-index-test -cursor-at=%s:8:11 \
 // RUN:              -cursor-at=%s:9:11 \
 // RUN:              -cursor-at=%s:25:11 \
@@ -59,6 +67,7 @@ void test2() {
 // RUN:              -cursor-at=%s:36:9 \
 // RUN:              -cursor-at=%s:37:9 \
 // RUN:              -cursor-at=%s:49:26 \
+// RUN:              -cursor-at=%s:57:12 \
 // RUN:       %s | FileCheck %s
 
 // CHECK:     8:11 MemberRefExpr=meth:3:16 {{.*}} Dynamic-call
@@ -67,9 +76,10 @@ void test2() {
 // CHECK-NOT: 26:3 {{.*}} Dynamic-call
 // CHECK-NOT: 29:3 {{.*}} Dynamic-call
 // CHECK:     29:3 {{.*}} Receiver-type=ObjCInterface
-// CHECK:     34:7 MemberRefExpr=meth:3:16 {{.*}} Dynamic-call
+// CHECK:     34:7 MemberRefExpr=meth:3:16 {{.*}} Dynamic-call Receiver-type=Pointer
 // CHECK:     35:3 ObjCMessageExpr=meth:14:8 {{.*}} Dynamic-call Receiver-type=ObjCObjectPointer
 // CHECK-NOT: 36:3 {{.*}} Dynamic-call
 // CHECK:     36:3 {{.*}} Receiver-type=ObjCInterface
 // CHECK:     37:3 ObjCMessageExpr=ClsMeth:15:8 {{.*}} Dynamic-call Receiver-type=ObjCClass
 // CHECK-NOT: 49:10 {{.*}} Dynamic-call
+// CHECK:     57:12 MemberRefExpr=someProp:53:23 {{.*}} Dynamic-call  Receiver-type=ObjCObjectPointer
diff --git a/test/Index/index-module.m b/test/Index/index-module.m
index 51faea2d32bb..6f3d848ecbf9 100644
--- a/test/Index/index-module.m
+++ b/test/Index/index-module.m
@@ -28,7 +28,7 @@ int glob;
 // CHECK-DMOD-NEXT: [ppIncludedFile]: [[DMOD_OTHER_H:.*/Modules/Inputs/DependsOnModule\.framework[/\\]Headers[/\\]other\.h]] | {{.*}} | hash loc: <invalid> | {{.*}} | module: DependsOnModule
 // CHECK-DMOD-NEXT: [ppIncludedFile]: [[DMOD_NOT_CXX_H:.*/Modules/Inputs/DependsOnModule\.framework[/\\]Headers[/\\]not_cxx\.h]] | {{.*}} | hash loc: <invalid> | {{.*}} | module: DependsOnModule.NotCXX
 // CHECK-DMOD-NEXT: [ppIncludedFile]: [[DMOD_SUB_H:.*/Modules/Inputs/DependsOnModule\.framework[/\\]Frameworks[/\\]SubFramework\.framework[/\\]Headers[/\\]SubFramework\.h]] | {{.*}} | hash loc: <invalid> | {{.*}} | module: DependsOnModule.SubFramework
-// CHECK-DMOD-NEXT: [ppIncludedFile]: [[DMOD_SUB_OTHER_H:.*/Modules/Inputs/DependsOnModule.framework[/\\]Frameworks/SubFramework\.framework/Headers/Other\.h]] | name: "SubFramework/Other.h" | hash loc: [[DMOD_SUB_H]]:1:1 | isImport: 0 | isAngled: 0 | isModule: 0 | module: DependsOnModule.SubFramework.Other
+// CHECK-DMOD-NEXT: [ppIncludedFile]: [[DMOD_SUB_OTHER_H:.*/Modules/Inputs/DependsOnModule.framework[/\\]Frameworks[/\\]SubFramework\.framework[/\\]Headers[/\\]Other\.h]] | name: "SubFramework/Other.h" | hash loc: [[DMOD_SUB_H]]:1:1 | isImport: 0 | isAngled: 0 | isModule: 0 | module: DependsOnModule.SubFramework.Other
 // CHECK-DMOD-NEXT: [ppIncludedFile]: [[DMOD_PRIVATE_H:.*/Modules/Inputs/DependsOnModule.framework[/\\]PrivateHeaders[/\\]DependsOnModulePrivate.h]] | {{.*}} | hash loc: <invalid> | {{.*}} | module: DependsOnModule.Private.DependsOnModule
 // CHECK-DMOD-NEXT: [importedASTFile]: {{.*}}.cache{{(.sys)?[/\\]}}Module.pcm | loc: [[DMOD_MODULE_H]]:1:1 | name: "Module" | isImplicit: 1
 // CHECK-DMOD-NEXT: [indexDeclaration]: kind: variable | name: depends_on_module_other | {{.*}} | loc: [[DMOD_OTHER_H]]:1:5
diff --git a/test/Index/print-type.cpp b/test/Index/print-type.cpp
index ff150f7dd613..e152a7ed3dd1 100644
--- a/test/Index/print-type.cpp
+++ b/test/Index/print-type.cpp
@@ -71,10 +71,9 @@ struct Specialization<int>;
 Specialization<Specialization<bool>& > templRefParam;
 auto autoTemplRefParam = templRefParam;
 
-template<typename T, typename U = int>
-struct DefaultedTypeExample {};
-
-typedef DefaultedTypeExample<int> DefaultedTypeAlias;
+template<typename T> struct A {};
+template<typename T> using C = T;
+using baz = C<A<void>>;
 
 // RUN: c-index-test -test-print-type %s -std=c++14 | FileCheck %s
 // CHECK: Namespace=outer:1:11 (Definition) [type=] [typekind=Invalid] [isPOD=0]
@@ -120,7 +119,7 @@ typedef DefaultedTypeExample<int> DefaultedTypeAlias;
 // CHECK: TemplateRef=Baz:9:8 [type=] [typekind=Invalid] [isPOD=0]
 // CHECK: IntegerLiteral= [type=int] [typekind=Int] [isPOD=1]
 // CHECK: TemplateRef=Foo:4:8 [type=] [typekind=Invalid] [isPOD=0]
-// CHECK: FieldDecl=qux:29:38 (Definition) [type=Qux<int, char *, Foo<int>, outer::inner::Bar::FooType>] [typekind=Unexposed] [templateargs/4= [type=int] [typekind=Int] [type=char *] [typekind=Pointer] [type=outer::Foo<int>] [typekind=Record] [type=int] [typekind=Int]] [canonicaltype=outer::Qux<int, char *, outer::Foo<int>, int>] [canonicaltypekind=Record] [canonicaltemplateargs/4= [type=int] [typekind=Int] [type=char *] [typekind=Pointer] [type=outer::Foo<int>] [typekind=Record] [type=int] [typekind=Int]] [isPOD=1]
+// CHECK: FieldDecl=qux:29:38 (Definition) [type=Qux<int, char *, Foo<int>, outer::inner::Bar::FooType>] [typekind=Unexposed] [templateargs/4= [type=int] [typekind=Int] [type=char *] [typekind=Pointer] [type=Foo<int>] [typekind=Unexposed] [type=outer::inner::Bar::FooType] [typekind=Typedef]] [canonicaltype=outer::Qux<int, char *, outer::Foo<int>, int>] [canonicaltypekind=Record] [canonicaltemplateargs/4= [type=int] [typekind=Int] [type=char *] [typekind=Pointer] [type=outer::Foo<int>] [typekind=Record] [type=int] [typekind=Int]] [isPOD=1]
 // CHECK: TemplateRef=Qux:12:8 [type=] [typekind=Invalid] [isPOD=0]
 // CHECK: TemplateRef=Foo:4:8 [type=] [typekind=Invalid] [isPOD=0]
 // CHECK: FunctionTemplate=tbar:36:3 [type=T (int)] [typekind=FunctionProto] [canonicaltype=type-parameter-0-0 (int)] [canonicaltypekind=FunctionProto] [resulttype=T] [resulttypekind=Unexposed] [isPOD=0]
@@ -182,4 +181,4 @@ typedef DefaultedTypeExample<int> DefaultedTypeAlias;
 // CHECK: VarDecl=autoTemplRefParam:72:6 (Definition) [type=Specialization<Specialization<bool> &>] [typekind=Auto] [templateargs/1= [type=Specialization<bool> &] [typekind=LValueReference]] [canonicaltype=Specialization<Specialization<bool> &>] [canonicaltypekind=Record] [canonicaltemplateargs/1= [type=Specialization<bool> &] [typekind=LValueReference]] [isPOD=1]
 // CHECK: UnexposedExpr=templRefParam:71:40 [type=const Specialization<Specialization<bool> &>] [typekind=Unexposed] const [templateargs/1= [type=Specialization<bool> &] [typekind=LValueReference]] [canonicaltype=const Specialization<Specialization<bool> &>] [canonicaltypekind=Record] [canonicaltemplateargs/1= [type=Specialization<bool> &] [typekind=LValueReference]] [isPOD=1]
 // CHECK: DeclRefExpr=templRefParam:71:40 [type=Specialization<Specialization<bool> &>] [typekind=Unexposed] [templateargs/1= [type=Specialization<bool> &] [typekind=LValueReference]] [canonicaltype=Specialization<Specialization<bool> &>] [canonicaltypekind=Record] [canonicaltemplateargs/1= [type=Specialization<bool> &] [typekind=LValueReference]] [isPOD=1]
-// CHECK: TypedefDecl=DefaultedTypeAlias:77:35 (Definition) [type=DefaultedTypeAlias] [typekind=Typedef] [templateargs/2= [type=int] [typekind=Int] [type=int] [typekind=Int]] [canonicaltype=DefaultedTypeExample<int, int>] [canonicaltypekind=Record] [canonicaltemplateargs/2= [type=int] [typekind=Int] [type=int] [typekind=Int]] [isPOD=0]
+// CHECK: TypeAliasDecl=baz:76:7 (Definition) [type=baz] [typekind=Typedef] [templateargs/1= [type=A<void>] [typekind=Unexposed]] [canonicaltype=A<void>] [canonicaltypekind=Record] [canonicaltemplateargs/1= [type=void] [typekind=Void]] [isPOD=0]
diff --git a/test/Index/target-info.c b/test/Index/target-info.c
new file mode 100644
index 000000000000..98a3ca32b570
--- /dev/null
+++ b/test/Index/target-info.c
@@ -0,0 +1,6 @@
+// RUN: c-index-test -test-print-target-info %s --target=i386-unknown-linux-gnu | FileCheck %s
+// RUN: c-index-test -test-print-target-info %s --target=x86_64-unknown-linux-gnu | FileCheck --check-prefix=CHECK-1 %s
+// CHECK: TargetTriple: i386-unknown-linux-gnu
+// CHECK: PointerWidth: 32
+// CHECK-1: TargetTriple: x86_64-unknown-linux-gnu
+// CHECK-1: PointerWidth: 64
diff --git a/test/Index/usrs.cpp b/test/Index/usrs.cpp
index 8ad17021b50d..2bd5744371ad 100644
--- a/test/Index/usrs.cpp
+++ b/test/Index/usrs.cpp
@@ -95,6 +95,14 @@ class TC1 {
   void meth(TC1);
 };
 
+typedef __attribute__((__ext_vector_type__(3))) float float3;
+
+typedef float __m128 __attribute__((__vector_size__(16)));
+
+float3 vectorOverload(float3 f);
+
+__m128 vectorOverload(__m128 f);
+
 // RUN: c-index-test -test-load-source-usrs all -fno-delayed-template-parsing %s | FileCheck %s
 // CHECK: usrs.cpp c:@N@foo Extent=[1:1 - 4:2]
 // CHECK: usrs.cpp c:@N@foo@x Extent=[2:3 - 2:8]
@@ -172,3 +180,6 @@ class TC1 {
 // CHECK: usrs.cpp c:usrs.cpp@S@usrs.cpp@1510@FI@x Extent=[91:10 - 91:15]
 
 // CHECK: usrs.cpp c:@ST>1#T@TC1@F@meth#>@ST>1#T@TC11t0.0# Extent=[95:3 - 95:17]
+
+// CHECK: usrs.cpp c:@F@vectorOverload#]3f# Extent=[102:1 - 102:32]
+// CHECK: usrs.cpp c:@F@vectorOverload#[4f# Extent=[104:1 - 104:32]
diff --git a/test/Modules/ExtDebugInfo.cpp b/test/Modules/ExtDebugInfo.cpp
index 3bd58a3da551..fd3bb940751f 100644
--- a/test/Modules/ExtDebugInfo.cpp
+++ b/test/Modules/ExtDebugInfo.cpp
@@ -76,7 +76,7 @@ void foo() {
 // CHECK-SAME:             flags: DIFlagFwdDecl,
 // CHECK-SAME:             identifier:  "_ZTSN8DebugCXX4EnumE")
 
-// CHECK: ![[NS]] = !DINamespace(name: "DebugCXX", scope: ![[MOD:[0-9]+]],
+// CHECK: ![[NS]] = !DINamespace(name: "DebugCXX", scope: ![[MOD:[0-9]+]])
 // CHECK: ![[MOD]] = !DIModule(scope: null, name: {{.*}}DebugCXX
 
 // This type is anchored in the module by an explicit template instantiation.
diff --git a/test/Modules/Inputs/diag_flags.h b/test/Modules/Inputs/diag_flags.h
new file mode 100644
index 000000000000..3b85c84c6cfd
--- /dev/null
+++ b/test/Modules/Inputs/diag_flags.h
@@ -0,0 +1 @@
+struct Padded { char x; int y; };
diff --git a/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Headers/Bar.h b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Headers/Bar.h
new file mode 100644
index 000000000000..fb5da09bac6c
--- /dev/null
+++ b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Headers/Bar.h
@@ -0,0 +1 @@
+#define BAR_PUBLIC 1
diff --git a/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Headers/FooPublic.h b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Headers/FooPublic.h
new file mode 100644
index 000000000000..cbbb44f42c71
--- /dev/null
+++ b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Headers/FooPublic.h
@@ -0,0 +1 @@
+// FooPublic.h
diff --git a/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Modules/module.modulemap b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Modules/module.modulemap
new file mode 100644
index 000000000000..af67e657405a
--- /dev/null
+++ b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Modules/module.modulemap
@@ -0,0 +1,5 @@
+framework module Foo {
+    umbrella header "FooPublic.h"
+    requires objc
+    export *
+}
diff --git a/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Modules/module.private.modulemap b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Modules/module.private.modulemap
new file mode 100644
index 000000000000..f6d9dfdcab33
--- /dev/null
+++ b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/Modules/module.private.modulemap
@@ -0,0 +1,5 @@
+explicit module Foo.Private {
+    umbrella header "Foo.h"
+    requires objc
+    export *
+}
diff --git a/test/Modules/Inputs/incomplete-umbrella/Foo.framework/PrivateHeaders/Baz.h b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/PrivateHeaders/Baz.h
new file mode 100644
index 000000000000..98064e08146d
--- /dev/null
+++ b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/PrivateHeaders/Baz.h
@@ -0,0 +1 @@
+#define BAZ_PRIVATE 1
diff --git a/test/Modules/Inputs/incomplete-umbrella/Foo.framework/PrivateHeaders/Foo.h b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/PrivateHeaders/Foo.h
new file mode 100644
index 000000000000..9381133344b1
--- /dev/null
+++ b/test/Modules/Inputs/incomplete-umbrella/Foo.framework/PrivateHeaders/Foo.h
@@ -0,0 +1 @@
+// Foo.h
diff --git a/test/Modules/Inputs/malformed-overload/X.h b/test/Modules/Inputs/malformed-overload/X.h
new file mode 100644
index 000000000000..b659406e16ed
--- /dev/null
+++ b/test/Modules/Inputs/malformed-overload/X.h
@@ -0,0 +1,2 @@
+@class NSString;
+extern void NSLog(NSString *format, ...) __attribute__((format(__NSString__, 1, 2))) __attribute__((not_tail_called));
diff --git a/test/Modules/Inputs/malformed-overload/module.modulemap b/test/Modules/Inputs/malformed-overload/module.modulemap
new file mode 100644
index 000000000000..8fe4c92a1738
--- /dev/null
+++ b/test/Modules/Inputs/malformed-overload/module.modulemap
@@ -0,0 +1,4 @@
+module X {
+  header "X.h"
+  export *
+}
diff --git a/test/Modules/Inputs/module.map b/test/Modules/Inputs/module.map
index b95eec351e86..7416d7008b85 100644
--- a/test/Modules/Inputs/module.map
+++ b/test/Modules/Inputs/module.map
@@ -261,6 +261,10 @@ module config {
   config_macros [exhaustive] WANT_FOO, WANT_BAR
 }
 
+module diag_flags {
+  header "diag_flags.h"
+}
+
 module diag_pragma {
   header "diag_pragma.h"
 }
diff --git a/test/Modules/crash-vfs-path-emptydir-entries.m b/test/Modules/crash-vfs-path-emptydir-entries.m
index e44714bee7f6..d96adbbf99ba 100644
--- a/test/Modules/crash-vfs-path-emptydir-entries.m
+++ b/test/Modules/crash-vfs-path-emptydir-entries.m
@@ -27,7 +27,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
diff --git a/test/Modules/crash-vfs-path-symlink-component.m b/test/Modules/crash-vfs-path-symlink-component.m
index 5be492514a09..4723a77c7e93 100644
--- a/test/Modules/crash-vfs-path-symlink-component.m
+++ b/test/Modules/crash-vfs-path-symlink-component.m
@@ -28,7 +28,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
@@ -65,4 +65,4 @@
 // RUN:     -fmodules-cache-path=%t/m/ 2>&1 \
 // RUN:     | FileCheck %s --check-prefix=CHECKOVERLAY
 
-// CHECKOVERLAY: @import cstd.stdio; /* clang -E: implicit import for "/{{[^ ].*}}/i/usr/x/../stdio.h" */
+// CHECKOVERLAY: #pragma clang module import cstd.stdio /* clang -E: implicit import
diff --git a/test/Modules/crash-vfs-path-symlink-topheader.m b/test/Modules/crash-vfs-path-symlink-topheader.m
index 51a14c69c077..8e0c2d4c9226 100644
--- a/test/Modules/crash-vfs-path-symlink-topheader.m
+++ b/test/Modules/crash-vfs-path-symlink-topheader.m
@@ -29,7 +29,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
diff --git a/test/Modules/crash-vfs-path-traversal.m b/test/Modules/crash-vfs-path-traversal.m
index cc56e53cf1bf..cd12cadcf18e 100644
--- a/test/Modules/crash-vfs-path-traversal.m
+++ b/test/Modules/crash-vfs-path-traversal.m
@@ -25,7 +25,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
@@ -62,4 +62,4 @@
 // RUN:     -fmodules-cache-path=%t/m/ 2>&1 \
 // RUN:     | FileCheck %s --check-prefix=CHECKOVERLAY
 
-// CHECKOVERLAY: @import cstd.stdio; /* clang -E: implicit import for "/{{[^ ].*}}/usr/././//////include/../include/./././../include/stdio.h" */
+// CHECKOVERLAY: #pragma clang module import cstd.stdio /* clang -E: implicit import
diff --git a/test/Modules/crash-vfs-relative-incdir.m b/test/Modules/crash-vfs-relative-incdir.m
index 63cd9827c013..ed02de8d7e1e 100644
--- a/test/Modules/crash-vfs-relative-incdir.m
+++ b/test/Modules/crash-vfs-relative-incdir.m
@@ -21,7 +21,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
diff --git a/test/Modules/crash-vfs-relative-overlay.m b/test/Modules/crash-vfs-relative-overlay.m
index 54ba13bbca39..e55f4c8f272e 100644
--- a/test/Modules/crash-vfs-relative-overlay.m
+++ b/test/Modules/crash-vfs-relative-overlay.m
@@ -24,7 +24,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
@@ -58,4 +58,4 @@
 // RUN:     -fmodules-cache-path=%t/m/ 2>&1 \
 // RUN:     | FileCheck %s --check-prefix=CHECKOVERLAY
 
-// CHECKOVERLAY: @import cstd.stdio; /* clang -E: implicit import for "/{{[^ ].*}}/usr/include/stdio.h" */
+// CHECKOVERLAY: #pragma clang module import cstd.stdio /* clang -E: implicit import
diff --git a/test/Modules/crash-vfs-run-reproducer.m b/test/Modules/crash-vfs-run-reproducer.m
index 72771a2f9479..eba56c53f6fa 100644
--- a/test/Modules/crash-vfs-run-reproducer.m
+++ b/test/Modules/crash-vfs-run-reproducer.m
@@ -21,7 +21,7 @@
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.m
 // CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
 
-// CHECKSRC: @import cstd.stdio;
+// CHECKSRC: #pragma clang module import cstd.stdio
 
 // CHECKSH: # Crash reproducer
 // CHECKSH-NEXT: # Driver args: "-fsyntax-only"
diff --git a/test/Modules/diag-flags.cpp b/test/Modules/diag-flags.cpp
new file mode 100644
index 000000000000..adbbd08ac8dc
--- /dev/null
+++ b/test/Modules/diag-flags.cpp
@@ -0,0 +1,22 @@
+// RUN: rm -rf %t
+//
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fmodules -fimplicit-module-maps -emit-module -fmodules-cache-path=%t -fmodule-name=diag_flags -x c++ %S/Inputs/module.map -fmodules-ts
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fmodules -fimplicit-module-maps -verify -fmodules-cache-path=%t -I %S/Inputs %s -fmodules-ts
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fmodules -fimplicit-module-maps -verify -fmodules-cache-path=%t -I %S/Inputs %s -fmodules-ts -DIMPLICIT_FLAG -Werror=padded
+//
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fmodules -fimplicit-module-maps -emit-module -fmodule-name=diag_flags -x c++ %S/Inputs/module.map -fmodules-ts -o %t/explicit.pcm -Werror=string-plus-int -Wpadded
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fmodules -fimplicit-module-maps -verify -fmodules-cache-path=%t -I %S/Inputs %s -fmodules-ts -DEXPLICIT_FLAG -fmodule-file=%t/explicit.pcm
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fmodules -fimplicit-module-maps -verify -fmodules-cache-path=%t -I %S/Inputs %s -fmodules-ts -DEXPLICIT_FLAG -fmodule-file=%t/explicit.pcm -Werror=padded
+
+import diag_flags;
+
+// Diagnostic flags from the module user make no difference to diagnostics
+// emitted within the module when using an explicitly-loaded module.
+#ifdef IMPLICIT_FLAG
+// expected-error@diag_flags.h:14 {{padding struct}}
+#elif defined(EXPLICIT_FLAG)
+// expected-warning@diag_flags.h:14 {{padding struct}}
+#else
+// expected-no-diagnostics
+#endif
+unsigned n = sizeof(Padded);
diff --git a/test/Modules/import-syntax.c b/test/Modules/import-syntax.c
new file mode 100644
index 000000000000..a29e07aa1c2b
--- /dev/null
+++ b/test/Modules/import-syntax.c
@@ -0,0 +1,35 @@
+// RUN: rm -rf %t
+//
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x c -DINCLUDE %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x objective-c -DINCLUDE %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x c++ -DINCLUDE %s
+//
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x objective-c -DAT_IMPORT=1 %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x objective-c++ -DAT_IMPORT=1 %s
+//
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x c++ -fmodules-ts -DIMPORT=1 %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x objective-c++ -fmodules-ts -DIMPORT=1 %s
+//
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x c -DPRAGMA %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x objective-c -DPRAGMA %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -fimplicit-module-maps -I%S/Inputs -verify -x c++ -DPRAGMA %s
+
+// expected-no-diagnostics
+
+// All forms of module import should make both declarations and macros visible.
+
+#if INCLUDE
+#include "dummy.h"
+#elif AT_IMPORT
+@import dummy;
+#elif IMPORT
+import dummy;
+#elif PRAGMA
+#pragma clang module import dummy
+#endif
+
+#ifndef DUMMY_H
+#error "macros not visible"
+#endif
+
+void *p = &dummy1;
diff --git a/test/Modules/incomplete-umbrella.m b/test/Modules/incomplete-umbrella.m
new file mode 100644
index 000000000000..8760b815718b
--- /dev/null
+++ b/test/Modules/incomplete-umbrella.m
@@ -0,0 +1,15 @@
+// RUN: rm -rf %t
+// RUN: not %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -F%S/Inputs/incomplete-umbrella -fsyntax-only %s 2>&1 | FileCheck %s
+
+#import <Foo/Foo.h>
+#import <Foo/Bar.h>
+#import <Foo/Baz.h>
+@import Foo.Private;
+
+// CHECK: warning: umbrella header for module 'Foo' does not include header 'Bar.h'
+// CHECK: warning: umbrella header for module 'Foo.Private' does not include header 'Baz.h'
+int foo() {
+  int a = BAR_PUBLIC;
+  int b = BAZ_PRIVATE;
+  return 0;
+}
diff --git a/test/Modules/malformed-overload.m b/test/Modules/malformed-overload.m
new file mode 100644
index 000000000000..e080201d8e42
--- /dev/null
+++ b/test/Modules/malformed-overload.m
@@ -0,0 +1,9 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fsyntax-only -I%S/Inputs/malformed-overload -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -verify %s
+NSLog(@"%@", path); // expected-error {{expected parameter declarator}} expected-error {{expected ')'}} expected-warning {{type specifier missing}} expected-warning {{incompatible redeclaration}} expected-note {{to match this '('}} expected-note {{'NSLog' is a builtin with type}}
+#import "X.h"
+
+@class NSString;
+void f(NSString *a) {
+ NSLog(@"***** failed to get URL for %@", a);
+}
diff --git a/test/Modules/odr_hash.cpp b/test/Modules/odr_hash.cpp
index 2ec8005ce509..e57c36f3864c 100644
--- a/test/Modules/odr_hash.cpp
+++ b/test/Modules/odr_hash.cpp
@@ -887,6 +887,52 @@ Bravo<char> golf;
 #endif
 }
 
+namespace DifferentParameterNameInTemplate {
+#if defined(FIRST) || defined(SECOND)
+template <typename T>
+struct S {
+  typedef T Type;
+
+  static void Run(const Type *name_one);
+};
+
+template <typename T>
+void S<T>::Run(const T *name_two) {}
+
+template <typename T>
+struct Foo {
+  ~Foo() { Handler::Run(nullptr); }
+  Foo() {}
+
+  class Handler : public S<T> {};
+
+  void Get(typename Handler::Type *x = nullptr) {}
+  void Add() { Handler::Run(nullptr); }
+};
+#endif
+
+#if defined(FIRST)
+struct Beta;
+
+struct Alpha {
+  Alpha();
+  void Go() { betas.Get(); }
+  Foo<Beta> betas;
+};
+
+#elif defined(SECOND)
+struct Beta {};
+
+struct BetaHelper {
+  void add_Beta() { betas.Add(); }
+  Foo<Beta> betas;
+};
+
+#else
+Alpha::Alpha() {}
+#endif
+}
+
 // Keep macros contained to one file.
 #ifdef FIRST
 #undef FIRST
diff --git a/test/Modules/preprocess-module.cpp b/test/Modules/preprocess-module.cpp
new file mode 100644
index 000000000000..99fe8cf8c30b
--- /dev/null
+++ b/test/Modules/preprocess-module.cpp
@@ -0,0 +1,12 @@
+// RUN: rm -rf %t
+
+// RUN: not %clang_cc1 -fmodules -fmodule-name=file -I%S/Inputs/preprocess -x c++-module-map %S/Inputs/preprocess/module.modulemap -E 2>&1 | FileCheck %s --check-prefix=MISSING-FWD
+// MISSING-FWD: module 'fwd' is needed
+
+// RUN: %clang_cc1 -fmodules -fmodule-name=file -fmodules-cache-path=%t -I%S/Inputs/preprocess -x c++-module-map %S/Inputs/preprocess/module.modulemap -E | FileCheck %s
+// CHECK: # 1 "<module-includes>"
+// CHECK: # 1 "{{.*}}file.h" 1
+// CHECK: struct __FILE;
+// CHECK: #pragma clang module import fwd /* clang -E: implicit import for #include "fwd.h" */
+// CHECK: typedef struct __FILE FILE;
+// CHECK: # 2 "<module-includes>" 2
diff --git a/test/Modules/preprocess.cpp b/test/Modules/preprocess.cpp
index 0615331c8bd7..d855fed62d48 100644
--- a/test/Modules/preprocess.cpp
+++ b/test/Modules/preprocess.cpp
@@ -1,24 +1,30 @@
 // RUN: rm -rf %t
 // RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs -x c++ -E %s | \
-// RUN:   FileCheck -strict-whitespace %s --check-prefix=CHECK --check-prefix=CXX --check-prefix=CXX-DASHE
+// RUN:   FileCheck -strict-whitespace %s
 // RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs -x objective-c -E %s | \
-// RUN:   FileCheck -strict-whitespace %s --check-prefix=CHECK --check-prefix=OBJC
+// RUN:   FileCheck -strict-whitespace %s
 // RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs -x c++ -E -frewrite-includes %s | \
-// RUN:   FileCheck -strict-whitespace %s --check-prefix=CHECK --check-prefix=CXX
+// RUN:   FileCheck -strict-whitespace %s --check-prefix=REWRITE
 // RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs -x objective-c -E -frewrite-includes %s | \
-// RUN:   FileCheck -strict-whitespace %s --check-prefix=CHECK --check-prefix=OBJC
+// RUN:   FileCheck -strict-whitespace %s --check-prefix=REWRITE
 #include "dummy.h"
 #include "dummy.h"
 foo bar baz
 
-// The weird {{ }} here is to prevent the -frewrite-includes test from matching its own CHECK lines.
+// EOF marker to ensure -frewrite-includes doesn't match its own CHECK lines.
 
-// CXX: #include{{ }}"dummy.h"
-// CXX-DASHE-SAME: /* clang -E: implicit import for module dummy */
-// CXX: #include{{ }}"dummy.h"
-// CXX-DASHE-SAME: /* clang -E: implicit import for module dummy */
-// CXX: foo bar baz
+// REWRITE: #if 0
+// REWRITE: #include{{ }}"dummy.h"
+// REWRITE: #endif
 
-// OBJC: @import{{ }}dummy; /* clang 
-// OBJC: @import{{ }}dummy; /* clang 
-// OBJC: foo bar baz
+// CHECK: #pragma clang module import dummy /* clang {{.*}} implicit import
+
+// REWRITE: #if 0
+// REWRITE: #include{{ }}"dummy.h"
+// REWRITE: #endif
+
+// CHECK: #pragma clang module import dummy /* clang {{.*}} implicit import
+
+// CHECK: foo bar baz
+
+// REWRITE: // {{EOF}} marker
diff --git a/test/Modules/preprocess.m b/test/Modules/preprocess.m
index 8d740d1de287..37a68154d2e3 100644
--- a/test/Modules/preprocess.m
+++ b/test/Modules/preprocess.m
@@ -16,11 +16,11 @@ void test() {
 
 
 // CHECK: int left_and_right(int *);{{$}}
-// CHECK-NEXT: @import diamond_left; /* clang -E: implicit import for "{{.*}}diamond_left.h" */{{$}}
+// CHECK-NEXT: #pragma clang module import diamond_left /* clang -E: implicit import for #import "diamond_left.h" */{{$}}
 
-// CHECK: @import diamond_right; /* clang -E: implicit import for "{{.*}}diamond_right.h" */{{$}}
-// CHECK: @import diamond_right; /* clang -E: implicit import for "{{.*}}diamond_right.h" */{{$}}
-// CHECK: @import file; /* clang -E: implicit import for "{{.*}}file.h" */{{$}}
+// CHECK: #pragma clang module import diamond_right /* clang -E: implicit import for #import "diamond_right.h" */{{$}}
+// CHECK: #pragma clang module import diamond_right /* clang -E: implicit import for #import "diamond_right.h" */{{$}}
+// CHECK: #pragma clang module import file /* clang -E: implicit import for #include "file.h" */{{$}}
 // CHECK-NEXT: void test() {{{$}}
 // CHECK-NEXT:    top_left_before();{{$}}
 // CHECK-NEXT:    left_and_right();{{$}}
diff --git a/test/OpenMP/distribute_parallel_for_simd_aligned_messages.cpp b/test/OpenMP/distribute_parallel_for_simd_aligned_messages.cpp
index f865e0be424f..2d99d7d8f4bc 100644
--- a/test/OpenMP/distribute_parallel_for_simd_aligned_messages.cpp
+++ b/test/OpenMP/distribute_parallel_for_simd_aligned_messages.cpp
@@ -134,9 +134,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
 
 #pragma omp target
diff --git a/test/OpenMP/distribute_simd_aligned_messages.cpp b/test/OpenMP/distribute_simd_aligned_messages.cpp
index 10beb7198a6f..21b1bc9da1fa 100644
--- a/test/OpenMP/distribute_simd_aligned_messages.cpp
+++ b/test/OpenMP/distribute_simd_aligned_messages.cpp
@@ -134,9 +134,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
 
 #pragma omp target
diff --git a/test/OpenMP/for_simd_aligned_messages.cpp b/test/OpenMP/for_simd_aligned_messages.cpp
index 1d0918e449f3..3ff25870e5a0 100644
--- a/test/OpenMP/for_simd_aligned_messages.cpp
+++ b/test/OpenMP/for_simd_aligned_messages.cpp
@@ -107,9 +107,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
   #pragma omp for simd aligned // expected-error {{expected '(' after 'aligned'}}
   for (I k = 0; k < argc; ++k) ++k;
diff --git a/test/OpenMP/parallel_for_simd_aligned_messages.cpp b/test/OpenMP/parallel_for_simd_aligned_messages.cpp
index fc0f88cc38f8..eed80170039e 100644
--- a/test/OpenMP/parallel_for_simd_aligned_messages.cpp
+++ b/test/OpenMP/parallel_for_simd_aligned_messages.cpp
@@ -107,9 +107,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
   #pragma omp parallel for simd aligned // expected-error {{expected '(' after 'aligned'}}
   for (I k = 0; k < argc; ++k) ++k;
diff --git a/test/OpenMP/simd_aligned_messages.cpp b/test/OpenMP/simd_aligned_messages.cpp
index 81aec960f269..d936fed01439 100644
--- a/test/OpenMP/simd_aligned_messages.cpp
+++ b/test/OpenMP/simd_aligned_messages.cpp
@@ -107,9 +107,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
   #pragma omp simd aligned // expected-error {{expected '(' after 'aligned'}}
   for (I k = 0; k < argc; ++k) ++k;
diff --git a/test/OpenMP/target_parallel_for_simd_aligned_messages.cpp b/test/OpenMP/target_parallel_for_simd_aligned_messages.cpp
index 538d65b82b5e..655f90642f5b 100644
--- a/test/OpenMP/target_parallel_for_simd_aligned_messages.cpp
+++ b/test/OpenMP/target_parallel_for_simd_aligned_messages.cpp
@@ -107,9 +107,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
   #pragma omp target parallel for simd aligned // expected-error {{expected '(' after 'aligned'}}
   for (I k = 0; k < argc; ++k) ++k;
diff --git a/test/OpenMP/target_simd_aligned_messages.cpp b/test/OpenMP/target_simd_aligned_messages.cpp
index ae2859d5b61f..76a37f64984d 100644
--- a/test/OpenMP/target_simd_aligned_messages.cpp
+++ b/test/OpenMP/target_simd_aligned_messages.cpp
@@ -107,9 +107,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
   #pragma omp target simd aligned // expected-error {{expected '(' after 'aligned'}}
   for (I k = 0; k < argc; ++k) ++k;
diff --git a/test/OpenMP/target_teams_distribute_parallel_for_simd_aligned_messages.cpp b/test/OpenMP/target_teams_distribute_parallel_for_simd_aligned_messages.cpp
index df5468c82660..f121512733af 100644
--- a/test/OpenMP/target_teams_distribute_parallel_for_simd_aligned_messages.cpp
+++ b/test/OpenMP/target_teams_distribute_parallel_for_simd_aligned_messages.cpp
@@ -110,9 +110,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
 
 #pragma omp target teams distribute parallel for simd aligned // expected-error {{expected '(' after 'aligned'}}
diff --git a/test/OpenMP/target_teams_distribute_simd_aligned_messages.cpp b/test/OpenMP/target_teams_distribute_simd_aligned_messages.cpp
index e9df563ded2c..d91cfa9b54ae 100644
--- a/test/OpenMP/target_teams_distribute_simd_aligned_messages.cpp
+++ b/test/OpenMP/target_teams_distribute_simd_aligned_messages.cpp
@@ -110,9 +110,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
 
 #pragma omp target teams distribute simd aligned // expected-error {{expected '(' after 'aligned'}}
diff --git a/test/OpenMP/taskloop_simd_aligned_messages.cpp b/test/OpenMP/taskloop_simd_aligned_messages.cpp
index 6085660b705e..c4c41ebbafe4 100644
--- a/test/OpenMP/taskloop_simd_aligned_messages.cpp
+++ b/test/OpenMP/taskloop_simd_aligned_messages.cpp
@@ -107,9 +107,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
   #pragma omp taskloop simd aligned // expected-error {{expected '(' after 'aligned'}}
   for (I k = 0; k < argc; ++k) ++k;
diff --git a/test/OpenMP/teams_distribute_parallel_for_simd_aligned_messages.cpp b/test/OpenMP/teams_distribute_parallel_for_simd_aligned_messages.cpp
index 674057712ecf..97b200bb1641 100644
--- a/test/OpenMP/teams_distribute_parallel_for_simd_aligned_messages.cpp
+++ b/test/OpenMP/teams_distribute_parallel_for_simd_aligned_messages.cpp
@@ -123,9 +123,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
 
 #pragma omp target
diff --git a/test/OpenMP/teams_distribute_simd_aligned_messages.cpp b/test/OpenMP/teams_distribute_simd_aligned_messages.cpp
index 95a85b2d0db9..885432bb9a1e 100644
--- a/test/OpenMP/teams_distribute_simd_aligned_messages.cpp
+++ b/test/OpenMP/teams_distribute_simd_aligned_messages.cpp
@@ -123,9 +123,8 @@ S3 h; // expected-note 2 {{'h' defined here}}
 template<class I, class C> int foomain(I argc, C **argv) {
   I e(argc);
   I g(argc);
-  int i; // expected-note {{declared here}} expected-note {{'i' defined here}}
-  // expected-note@+2 {{declared here}}
-  // expected-note@+1 {{reference to 'i' is not a constant expression}}
+  int i; // expected-note {{'i' defined here}}
+  // expected-note@+1 {{declared here}}
   int &j = i;
 
 #pragma omp target
diff --git a/test/Preprocessor/Inputs/nonportable-hmaps/foo.hmap b/test/Preprocessor/Inputs/nonportable-hmaps/foo.hmap
new file mode 100644
index 000000000000..9036f208711c
--- /dev/null
+++ b/test/Preprocessor/Inputs/nonportable-hmaps/foo.hmap
diff --git a/test/Preprocessor/Inputs/nonportable-hmaps/headers/foo/Foo.h b/test/Preprocessor/Inputs/nonportable-hmaps/headers/foo/Foo.h
new file mode 100644
index 000000000000..e69de29bb2d1
--- /dev/null
+++ b/test/Preprocessor/Inputs/nonportable-hmaps/headers/foo/Foo.h
diff --git a/test/Preprocessor/init.c b/test/Preprocessor/init.c
index 5fb2011cd025..36ef9b213658 100644
--- a/test/Preprocessor/init.c
+++ b/test/Preprocessor/init.c
@@ -9690,3 +9690,12 @@
 // MSVC-X64-NEXT:#define __CLANG_ATOMIC_SHORT_LOCK_FREE 2
 // MSVC-X64-NEXT:#define __CLANG_ATOMIC_WCHAR_T_LOCK_FREE 2
 // MSVC-X86-NOT:#define __GCC_ATOMIC{{.*}}
+
+// RUN: %clang_cc1 -E -dM -ffreestanding                \
+// RUN:   -triple=aarch64-apple-ios9 < /dev/null        \
+// RUN: | FileCheck -check-prefix=DARWIN %s
+// RUN: %clang_cc1 -E -dM -ffreestanding                \
+// RUN:   -triple=aarch64-apple-macosx10.12 < /dev/null \
+// RUN: | FileCheck -check-prefix=DARWIN %s
+
+// DARWIN:#define __STDC_NO_THREADS__ 1
diff --git a/test/Preprocessor/nonportable-include-with-hmap.c b/test/Preprocessor/nonportable-include-with-hmap.c
new file mode 100644
index 000000000000..fc958e7e5e3f
--- /dev/null
+++ b/test/Preprocessor/nonportable-include-with-hmap.c
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -Eonly                        \
+// RUN:   -I%S/Inputs/nonportable-hmaps/foo.hmap \
+// RUN:   -I%S/Inputs/nonportable-hmaps          \
+// RUN:   %s -verify
+//
+// foo.hmap contains: Foo/Foo.h -> headers/foo/Foo.h
+//
+// Header search of "Foo/Foo.h" follows this path:
+//  1. Look for "Foo/Foo.h".
+//  2. Find "Foo/Foo.h" in "nonportable-hmaps/foo.hmap".
+//  3. Look for "headers/foo/Foo.h".
+//  4. Find "headers/foo/Foo.h" in "nonportable-hmaps".
+//  5. Return.
+//
+// There is nothing nonportable; -Wnonportable-include-path should not fire.
+#include "Foo/Foo.h" // expected-no-diagnostics
diff --git a/test/Preprocessor/pp-modules.c b/test/Preprocessor/pp-modules.c
index 09f3eee193f4..8c283c627132 100644
--- a/test/Preprocessor/pp-modules.c
+++ b/test/Preprocessor/pp-modules.c
@@ -3,13 +3,13 @@
 
 // CHECK: int bar();
 int bar();
-// CHECK: @import Module; /* clang -E: implicit import for "{{.*Headers[/\\]Module.h}}" */
+// CHECK: #pragma clang module import Module /* clang -E: implicit import for #include <Module/Module.h> */{{$}}
 #include <Module/Module.h>
 // CHECK: int foo();
 int foo();
-// CHECK: @import Module; /* clang -E: implicit import for "{{.*Headers[/\\]Module.h}}" */
+// CHECK: #pragma clang module import Module /* clang -E: implicit import for #include <Module/Module.h> */{{$}}
 #include <Module/Module.h>
 
 #include "pp-modules.h" // CHECK: # 1 "{{.*}}pp-modules.h" 1
-// CHECK: @import Module; /* clang -E: implicit import for "{{.*}}Module.h" */{{$}}
+// CHECK: #pragma clang module import Module /* clang -E: implicit import for #include <Module/Module.h> */{{$}}
 // CHECK: # 14 "{{.*}}pp-modules.c" 2
diff --git a/test/Preprocessor/pragma_diagnostic.c b/test/Preprocessor/pragma_diagnostic.c
index 3970dbbc8e2f..63d5907c67d0 100644
--- a/test/Preprocessor/pragma_diagnostic.c
+++ b/test/Preprocessor/pragma_diagnostic.c
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -fsyntax-only -verify -Wno-undef %s
+// RUN: %clang_cc1 -fsyntax-only -verify -Wno-undef -Wno-unknown-warning-option -DAVOID_UNKNOWN_WARNING %s
 // rdar://2362963
 
 #if FOO    // ok.
@@ -28,8 +29,10 @@
 #pragma GCC diagnostic error "-Wundef" 42  // expected-warning {{unexpected token in pragma diagnostic}}
 #pragma GCC diagnostic error "invalid-name"  // expected-warning {{pragma diagnostic expected option name (e.g. "-Wundef")}}
 
-#pragma GCC diagnostic error "-Winvalid-name"  // expected-warning {{unknown warning group '-Winvalid-name', ignored}}
-
+#pragma GCC diagnostic error "-Winvalid-name"
+#ifndef AVOID_UNKNOWN_WARNING
+// expected-warning@-2 {{unknown warning group '-Winvalid-name', ignored}}
+#endif
 
 // Testing pragma clang diagnostic with -Weverything
 void ppo(){} // First test that we do not diagnose on this.
diff --git a/test/Preprocessor/pragma_module.c b/test/Preprocessor/pragma_module.c
new file mode 100644
index 000000000000..d734f66efcef
--- /dev/null
+++ b/test/Preprocessor/pragma_module.c
@@ -0,0 +1,11 @@
+// RUN: %clang -cc1 -E -fmodules %s -verify
+
+// Just checking the syntax here; the semantics are tested elsewhere.
+#pragma clang module import // expected-error {{expected identifier in module name}}
+#pragma clang module import ! // expected-error {{expected identifier in module name}}
+#pragma clang module import if // expected-error {{expected identifier in module name}}
+#pragma clang module import foo ? bar // expected-error {{expected '.' or end of directive after module name}}
+#pragma clang module import foo. // expected-error {{expected identifier}}
+#pragma clang module import foo.bar.baz.quux // expected-error {{module 'foo' not found}}
+
+#error here // expected-error {{here}}
diff --git a/test/Preprocessor/stdint.c b/test/Preprocessor/stdint.c
index 28ccfef9f487..01b0da718627 100644
--- a/test/Preprocessor/stdint.c
+++ b/test/Preprocessor/stdint.c
@@ -28,8 +28,8 @@
 // ARM:typedef int8_t int_fast8_t;
 // ARM:typedef uint8_t uint_fast8_t;
 //
-// ARM:typedef int32_t intptr_t;
-// ARM:typedef uint32_t uintptr_t;
+// ARM:typedef long int intptr_t;
+// ARM:typedef long unsigned int uintptr_t;
 // 
 // ARM:typedef long long int intmax_t;
 // ARM:typedef long long unsigned int uintmax_t;
@@ -74,9 +74,9 @@
 // ARM:INT_FAST64_MAX_ 9223372036854775807LL
 // ARM:UINT_FAST64_MAX_ 18446744073709551615ULL
 //
-// ARM:INTPTR_MIN_ (-2147483647 -1)
-// ARM:INTPTR_MAX_ 2147483647
-// ARM:UINTPTR_MAX_ 4294967295U
+// ARM:INTPTR_MIN_ (-2147483647L -1)
+// ARM:INTPTR_MAX_ 2147483647L
+// ARM:UINTPTR_MAX_ 4294967295UL
 // ARM:PTRDIFF_MIN_ (-2147483647 -1)
 // ARM:PTRDIFF_MAX_ 2147483647
 // ARM:SIZE_MAX_ 4294967295U
@@ -136,8 +136,8 @@
 // I386:typedef int8_t int_fast8_t;
 // I386:typedef uint8_t uint_fast8_t;
 //
-// I386:typedef int32_t intptr_t;
-// I386:typedef uint32_t uintptr_t;
+// I386:typedef int intptr_t;
+// I386:typedef unsigned int uintptr_t;
 //
 // I386:typedef long long int intmax_t;
 // I386:typedef long long unsigned int uintmax_t;
@@ -243,8 +243,8 @@
 // MIPS:typedef int8_t int_fast8_t;
 // MIPS:typedef uint8_t uint_fast8_t;
 //
-// MIPS:typedef int32_t intptr_t;
-// MIPS:typedef uint32_t uintptr_t;
+// MIPS:typedef long int intptr_t;
+// MIPS:typedef long unsigned int uintptr_t;
 //
 // MIPS:typedef long long int intmax_t;
 // MIPS:typedef long long unsigned int uintmax_t;
@@ -289,9 +289,9 @@
 // MIPS:INT_FAST64_MAX_ 9223372036854775807LL
 // MIPS:UINT_FAST64_MAX_ 18446744073709551615ULL
 //
-// MIPS:INTPTR_MIN_ (-2147483647 -1)
-// MIPS:INTPTR_MAX_ 2147483647
-// MIPS:UINTPTR_MAX_ 4294967295U
+// MIPS:INTPTR_MIN_ (-2147483647L -1)
+// MIPS:INTPTR_MAX_ 2147483647L
+// MIPS:UINTPTR_MAX_ 4294967295UL
 // MIPS:PTRDIFF_MIN_ (-2147483647 -1)
 // MIPS:PTRDIFF_MAX_ 2147483647
 // MIPS:SIZE_MAX_ 4294967295U
@@ -350,8 +350,8 @@
 // MIPS64:typedef int8_t int_fast8_t;
 // MIPS64:typedef uint8_t uint_fast8_t;
 //
-// MIPS64:typedef int64_t intptr_t;
-// MIPS64:typedef uint64_t uintptr_t;
+// MIPS64:typedef long int intptr_t;
+// MIPS64:typedef long unsigned int uintptr_t;
 //
 // MIPS64:typedef long int intmax_t;
 // MIPS64:typedef long unsigned int uintmax_t;
@@ -450,8 +450,8 @@
 // MSP430:typedef int8_t int_fast8_t;
 // MSP430:typedef uint8_t uint_fast8_t;
 //
-// MSP430:typedef int16_t intptr_t;
-// MSP430:typedef uint16_t uintptr_t;
+// MSP430:typedef int intptr_t;
+// MSP430:typedef unsigned int uintptr_t;
 //
 // MSP430:typedef long long int intmax_t;
 // MSP430:typedef long long unsigned int uintmax_t;
@@ -557,8 +557,8 @@
 // PPC64:typedef int8_t int_fast8_t;
 // PPC64:typedef uint8_t uint_fast8_t;
 //
-// PPC64:typedef int64_t intptr_t;
-// PPC64:typedef uint64_t uintptr_t;
+// PPC64:typedef long int intptr_t;
+// PPC64:typedef long unsigned int uintptr_t;
 //
 // PPC64:typedef long int intmax_t;
 // PPC64:typedef long unsigned int uintmax_t;
@@ -664,8 +664,8 @@
 // PPC64-NETBSD:typedef int8_t int_fast8_t;
 // PPC64-NETBSD:typedef uint8_t uint_fast8_t;
 //
-// PPC64-NETBSD:typedef int64_t intptr_t;
-// PPC64-NETBSD:typedef uint64_t uintptr_t;
+// PPC64-NETBSD:typedef long int intptr_t;
+// PPC64-NETBSD:typedef long unsigned int uintptr_t;
 //
 // PPC64-NETBSD:typedef long long int intmax_t;
 // PPC64-NETBSD:typedef long long unsigned int uintmax_t;
@@ -710,12 +710,12 @@
 // PPC64-NETBSD:INT_FAST64_MAX_ 9223372036854775807LL
 // PPC64-NETBSD:UINT_FAST64_MAX_ 18446744073709551615ULL
 //
-// PPC64-NETBSD:INTPTR_MIN_ (-9223372036854775807LL -1)
-// PPC64-NETBSD:INTPTR_MAX_ 9223372036854775807LL
-// PPC64-NETBSD:UINTPTR_MAX_ 18446744073709551615ULL
-// PPC64-NETBSD:PTRDIFF_MIN_ (-9223372036854775807LL -1)
-// PPC64-NETBSD:PTRDIFF_MAX_ 9223372036854775807LL
-// PPC64-NETBSD:SIZE_MAX_ 18446744073709551615ULL
+// PPC64-NETBSD:INTPTR_MIN_ (-9223372036854775807L -1)
+// PPC64-NETBSD:INTPTR_MAX_ 9223372036854775807L
+// PPC64-NETBSD:UINTPTR_MAX_ 18446744073709551615UL
+// PPC64-NETBSD:PTRDIFF_MIN_ (-9223372036854775807L -1)
+// PPC64-NETBSD:PTRDIFF_MAX_ 9223372036854775807L
+// PPC64-NETBSD:SIZE_MAX_ 18446744073709551615UL
 //
 // PPC64-NETBSD:INTMAX_MIN_ (-9223372036854775807LL -1)
 // PPC64-NETBSD:INTMAX_MAX_ 9223372036854775807LL
@@ -772,8 +772,8 @@
 // PPC:typedef int8_t int_fast8_t;
 // PPC:typedef uint8_t uint_fast8_t;
 //
-// PPC:typedef int32_t intptr_t;
-// PPC:typedef uint32_t uintptr_t;
+// PPC:typedef long int intptr_t;
+// PPC:typedef long unsigned int uintptr_t;
 //
 // PPC:typedef long long int intmax_t;
 // PPC:typedef long long unsigned int uintmax_t;
@@ -818,12 +818,12 @@
 // PPC:INT_FAST64_MAX_ 9223372036854775807LL
 // PPC:UINT_FAST64_MAX_ 18446744073709551615ULL
 //
-// PPC:INTPTR_MIN_ (-2147483647 -1)
-// PPC:INTPTR_MAX_ 2147483647
-// PPC:UINTPTR_MAX_ 4294967295U
-// PPC:PTRDIFF_MIN_ (-2147483647 -1)
-// PPC:PTRDIFF_MAX_ 2147483647
-// PPC:SIZE_MAX_ 4294967295U
+// PPC:INTPTR_MIN_ (-2147483647L -1)
+// PPC:INTPTR_MAX_ 2147483647L
+// PPC:UINTPTR_MAX_ 4294967295UL
+// PPC:PTRDIFF_MIN_ (-2147483647L -1)
+// PPC:PTRDIFF_MAX_ 2147483647L
+// PPC:SIZE_MAX_ 4294967295UL
 //
 // PPC:INTMAX_MIN_ (-9223372036854775807LL -1)
 // PPC:INTMAX_MAX_ 9223372036854775807LL
@@ -879,8 +879,8 @@
 // S390X:typedef int8_t int_fast8_t;
 // S390X:typedef uint8_t uint_fast8_t;
 //
-// S390X:typedef int64_t intptr_t;
-// S390X:typedef uint64_t uintptr_t;
+// S390X:typedef long int intptr_t;
+// S390X:typedef long unsigned int uintptr_t;
 //
 // S390X:typedef long int intmax_t;
 // S390X:typedef long unsigned int uintmax_t;
@@ -986,8 +986,8 @@
 // SPARC:typedef int8_t int_fast8_t;
 // SPARC:typedef uint8_t uint_fast8_t;
 //
-// SPARC:typedef int32_t intptr_t;
-// SPARC:typedef uint32_t uintptr_t;
+// SPARC:typedef int intptr_t;
+// SPARC:typedef unsigned int uintptr_t;
 //
 // SPARC:typedef long long int intmax_t;
 // SPARC:typedef long long unsigned int uintmax_t;
@@ -1086,8 +1086,8 @@
 // TCE:typedef int8_t int_fast8_t;
 // TCE:typedef uint8_t uint_fast8_t;
 //
-// TCE:typedef int32_t intptr_t;
-// TCE:typedef uint32_t uintptr_t;
+// TCE:typedef int intptr_t;
+// TCE:typedef unsigned int uintptr_t;
 //
 // TCE:typedef long int intmax_t;
 // TCE:typedef long unsigned int uintmax_t;
@@ -1139,9 +1139,9 @@
 // TCE:PTRDIFF_MAX_ 2147483647
 // TCE:SIZE_MAX_ 4294967295U
 //
-// TCE:INTMAX_MIN_ (-2147483647 -1)
-// TCE:INTMAX_MAX_ 2147483647
-// TCE:UINTMAX_MAX_ 4294967295U
+// TCE:INTMAX_MIN_ (-2147483647L -1)
+// TCE:INTMAX_MAX_ 2147483647L
+// TCE:UINTMAX_MAX_ 4294967295UL
 //
 // TCE:SIG_ATOMIC_MIN_ (-2147483647 -1)
 // TCE:SIG_ATOMIC_MAX_ 2147483647
@@ -1194,8 +1194,8 @@
 // X86_64:typedef int8_t int_fast8_t;
 // X86_64:typedef uint8_t uint_fast8_t;
 //
-// X86_64:typedef int64_t intptr_t;
-// X86_64:typedef uint64_t uintptr_t;
+// X86_64:typedef long int intptr_t;
+// X86_64:typedef long unsigned int uintptr_t;
 //
 // X86_64:typedef long int intmax_t;
 // X86_64:typedef long unsigned int uintmax_t;
@@ -1314,8 +1314,8 @@
 // XCORE:typedef int8_t int_fast8_t;
 // XCORE:typedef uint8_t uint_fast8_t;
 //
-// XCORE:typedef int32_t intptr_t;
-// XCORE:typedef uint32_t uintptr_t;
+// XCORE:typedef int intptr_t;
+// XCORE:typedef unsigned int uintptr_t;
 //
 // XCORE:typedef long long int intmax_t;
 // XCORE:typedef long long unsigned int uintmax_t;
@@ -1398,9 +1398,14 @@
 // the identifiers used in the operations (int, uint, _t, INT, UINT, _MIN,
 // _MAX, and _C(v)) are themselves macros.
 //
-// RUN: %clang_cc1 -E -ffreestanding -U__UINTMAX_TYPE__ -U__INTMAX_TYPE__ -Dint=a -Duint=b -D_t=c -DINT=d -DUINT=e -D_MIN=f -D_MAX=g '-D_C(v)=h' -triple=i386-none-none %s | FileCheck -check-prefix JOIN %s
-// JOIN:typedef int32_t intptr_t;
-// JOIN:typedef uint32_t uintptr_t;
+// RUN: %clang_cc1 -E -ffreestanding                                 \
+// RUN:   -U__UINTPTR_TYPE__ -U__INTPTR_TYPE__                       \
+// RUN:   -U__UINTMAX_TYPE__ -U__INTMAX_TYPE__                       \
+// RUN:   -Dint=a -Duint=b -D_t=c -DINT=d -DUINT=e -D_MIN=f -D_MAX=g \
+// RUN:   '-D_C(v)=h' -triple=i386-none-none %s                      \
+// RUN: | FileCheck -check-prefix JOIN %s
+// JOIN:typedef __INTPTR_TYPE__ intptr_t;
+// JOIN:typedef __UINTPTR_TYPE__ uintptr_t;
 // JOIN:typedef __INTMAX_TYPE__ intmax_t;
 // JOIN:typedef __UINTMAX_TYPE__ uintmax_t;
 // JOIN:INTPTR_MIN_ (-2147483647 -1)
diff --git a/test/Profile/c-outdated-data.c b/test/Profile/c-outdated-data.c
index e61ad02d0757..b686f94d804e 100644
--- a/test/Profile/c-outdated-data.c
+++ b/test/Profile/c-outdated-data.c
@@ -4,23 +4,23 @@
 // doesn't play well with warnings that have no line number.
 
 // RUN: llvm-profdata merge %S/Inputs/c-outdated-data.proftext -o %t.profdata
-// RUN: %clang_cc1 -triple x86_64-apple-macosx10.9 -main-file-name c-outdated-data.c %s -o /dev/null -emit-llvm -fprofile-instrument-use-path=%t.profdata -Wprofile-instr-dropped 2>&1 | FileCheck %s
-// CHECK: warning: profile data may be out of date: of 3 functions, 1 has no data and 1 has mismatched data that will be ignored
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.9 -main-file-name c-outdated-data.c %s -o /dev/null -emit-llvm -fprofile-instrument-use-path=%t.profdata 2>&1 | FileCheck %s -check-prefix=NO_MISSING
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.9 -main-file-name c-outdated-data.c %s -o /dev/null -emit-llvm -Wprofile-instr-missing -fprofile-instrument-use-path=%t.profdata 2>&1 | FileCheck %s -check-prefix=WITH_MISSING
+
+// NO_MISSING: warning: profile data may be out of date: of 3 functions, 1 has mismatched data that will be ignored
+// NO_MISSING-NOT: 1 has no data
+
+// WITH_MISSING: warning: profile data may be out of date: of 3 functions, 1 has mismatched data that will be ignored
+// WITH_MISSING: warning: profile data may be incomplete: of 3 functions, 1 has no data
 
 void no_usable_data() {
   int i = 0;
 
   if (i) {}
-
-#ifdef GENERATE_OUTDATED_DATA
-  if (i) {}
-#endif
 }
 
-#ifndef GENERATE_OUTDATED_DATA
 void no_data() {
 }
-#endif
 
 int main(int argc, const char *argv[]) {
   no_usable_data();
diff --git a/test/Sema/integer-overflow.c b/test/Sema/integer-overflow.c
index e74bc119798b..62ee33e3d181 100644
--- a/test/Sema/integer-overflow.c
+++ b/test/Sema/integer-overflow.c
@@ -147,6 +147,19 @@ uint64_t check_integer_overflows(int i) {
   uint64_t a[10];
   a[4608 * 1024 * 1024] = 1i;
 
+// expected-warning@+2 {{overflow in expression; result is 536870912 with type 'int'}}
+  uint64_t *b;
+  uint64_t b2 = b[4608 * 1024 * 1024] + 1;
+
+// expected-warning@+1 2{{overflow in expression; result is 536870912 with type 'int'}}
+  int j1 = i ? (4608 * 1024 * 1024) : (4608 * 1024 * 1024);
+
+// expected-warning@+1 {{overflow in expression; result is 536870912 with type 'int'}}
+  int j2 = -(4608 * 1024 * 1024);
+
+// expected-warning@+1 {{overflow in expression; result is 536870912 with type 'int'}}
+  uint64_t j3 = b[4608 * 1024 * 1024];
+
 // expected-warning@+1 2{{overflow in expression; result is 536870912 with type 'int'}}
   return ((4608 * 1024 * 1024) + ((uint64_t)(4608 * 1024 * 1024)));
 }
diff --git a/test/SemaCXX/attr-non-x86-no_caller_saved_registers.cpp b/test/SemaCXX/attr-non-x86-no_caller_saved_registers.cpp
new file mode 100644
index 000000000000..00fa5bd7336b
--- /dev/null
+++ b/test/SemaCXX/attr-non-x86-no_caller_saved_registers.cpp
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 -std=c++11 -triple armv7-unknown-linux-gnueabi -fsyntax-only -verify %s
+
+struct a {
+  int __attribute__((no_caller_saved_registers)) b;                     // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+  static void foo(int *a) __attribute__((no_caller_saved_registers)) {} // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+};
+
+struct a test __attribute__((no_caller_saved_registers)); // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+
+__attribute__((no_caller_saved_registers(999))) void bar(int *) {} // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+
+__attribute__((no_caller_saved_registers)) void foo(int *){} // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+
+[[gnu::no_caller_saved_registers]] void foo2(int *) {} // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+
+typedef __attribute__((no_caller_saved_registers)) void (*foo3)(int *); // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+
+typedef void (*foo5)(int *);
+
+int (*foo4)(double a, __attribute__((no_caller_saved_registers)) float b); // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+
+int main(int argc, char **argv) {
+  void (*fp)(int *) = foo;
+  a::foo(&argc);
+  foo3 func = foo2;
+  func(&argc);
+  foo5 __attribute__((no_caller_saved_registers)) func2 = foo2; // expected-warning {{unknown attribute 'no_caller_saved_registers' ignored}}
+  return 0;
+}
diff --git a/test/SemaCXX/attr-x86-no_caller_saved_registers.cpp b/test/SemaCXX/attr-x86-no_caller_saved_registers.cpp
new file mode 100644
index 000000000000..48ccdec251af
--- /dev/null
+++ b/test/SemaCXX/attr-x86-no_caller_saved_registers.cpp
@@ -0,0 +1,33 @@
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-unknown-linux-gnu -fsyntax-only -verify %s
+
+struct a {
+  int b __attribute__((no_caller_saved_registers)); // expected-warning {{'no_caller_saved_registers' only applies to function types; type here is 'int'}}
+  static void foo(int *a) __attribute__((no_caller_saved_registers)) {}
+};
+
+struct a test __attribute__((no_caller_saved_registers)); // expected-warning {{'no_caller_saved_registers' only applies to function types; type here is 'struct a'}}
+
+__attribute__((no_caller_saved_registers(999))) void bar(int *) {} // expected-error {{'no_caller_saved_registers' attribute takes no arguments}}
+
+void __attribute__((no_caller_saved_registers)) foo(int *){}
+
+[[gnu::no_caller_saved_registers]] void foo2(int *) {}
+
+typedef __attribute__((no_caller_saved_registers)) void (*foo3)(int *);
+
+int (*foo4)(double a, __attribute__((no_caller_saved_registers)) float b); // expected-warning {{'no_caller_saved_registers' only applies to function types; type here is 'float'}}
+
+typedef void (*foo5)(int *);
+
+void foo6(){} // expected-note {{previous declaration is here}}
+
+void __attribute__((no_caller_saved_registers)) foo6(); // expected-error {{function declared with 'no_caller_saved_registers' attribute was previously declared without the 'no_caller_saved_registers' attribute}} 
+
+int main(int argc, char **argv) {
+  void (*fp)(int *) = foo; // expected-error {{cannot initialize a variable of type 'void (*)(int *)' with an lvalue of type 'void (int *)__attribute__((no_caller_saved_registers))'}}
+  a::foo(&argc);
+  foo3 func = foo2;
+  func(&argc);
+  foo5 __attribute__((no_caller_saved_registers)) func2 = foo2;
+  return 0;
+}
diff --git a/test/SemaCXX/constexpr-array-unknown-bound.cpp b/test/SemaCXX/constexpr-array-unknown-bound.cpp
new file mode 100644
index 000000000000..1d1462371984
--- /dev/null
+++ b/test/SemaCXX/constexpr-array-unknown-bound.cpp
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 %s -Wno-uninitialized -std=c++1z -fsyntax-only -verify
+
+const extern int arr[];
+constexpr auto p = arr; // ok
+constexpr int f(int i) {return p[i];} // expected-note {{read of dereferenced one-past-the-end pointer}}
+
+constexpr int arr[] {1, 2, 3};
+constexpr auto p2 = arr + 2; // ok
+constexpr int x = f(2); // ok
+constexpr int y = f(3); // expected-error {{constant expression}}
+// expected-note-re@-1 {{in call to 'f({{.*}})'}}
+
+struct A {int m[];} a;
+constexpr auto p3 = a.m; // ok
+constexpr auto p4 = a.m + 1; // expected-error {{constant expression}} expected-note {{constant bound}}
+
+void g(int i) {
+  int arr[i];
+  constexpr auto *p = arr + 2; // expected-error {{constant expression}} expected-note {{constant bound}}
+
+  // FIXME: Give a better diagnostic here. The issue is that computing
+  // sizeof(*arr2) within the array indexing fails due to the VLA.
+  int arr2[2][i];
+  constexpr int m = ((void)arr2[2], 0); // expected-error {{constant expression}}
+}
diff --git a/test/SemaCXX/typo-correction.cpp b/test/SemaCXX/typo-correction.cpp
index 48597ded1528..c59ee618f929 100644
--- a/test/SemaCXX/typo-correction.cpp
+++ b/test/SemaCXX/typo-correction.cpp
@@ -679,3 +679,30 @@ int g() {
       sizeof(c0is0)]; // expected-error {{use of undeclared identifier}}
 };
 }
+
+namespace avoidRedundantRedefinitionErrors {
+class Class {
+  void function(int pid); // expected-note {{'function' declared here}}
+};
+
+void Class::function2(int pid) { // expected-error {{out-of-line definition of 'function2' does not match any declaration in 'avoidRedundantRedefinitionErrors::Class'; did you mean 'function'?}}
+}
+
+// Expected no redefinition error here.
+void Class::function(int pid) { // expected-note {{previous definition is here}}
+}
+
+void Class::function(int pid) { // expected-error {{redefinition of 'function'}}
+}
+
+namespace ns {
+void create_test(); // expected-note {{'create_test' declared here}}
+}
+
+void ns::create_test2() { // expected-error {{out-of-line definition of 'create_test2' does not match any declaration in namespace 'avoidRedundantRedefinitionErrors::ns'; did you mean 'create_test'?}}
+}
+
+// Expected no redefinition error here.
+void ns::create_test() {
+}
+}
diff --git a/test/SemaObjC/x86-method-vector-values.m b/test/SemaObjC/x86-method-vector-values.m
new file mode 100644
index 000000000000..6c5189d08427
--- /dev/null
+++ b/test/SemaObjC/x86-method-vector-values.m
@@ -0,0 +1,132 @@
+// RUN: %clang_cc1 -verify -DMAC -triple=i686-apple-macosx10.10 -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -DMAC -triple=i686-apple-macosx10.4 -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -DMAC -triple=i686-apple-darwin14 -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -triple=i686-apple-ios8 -Wno-objc-root-class %s
+
+// RUN: %clang_cc1 -verify -DALLOW -DMAC -triple=i686-apple-macosx10.11 -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -DALLOW -DMAC -triple=i686-apple-darwin15 -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -DALLOW -DIOS -triple=i686-apple-ios9 -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -DALLOW -DOTHER -triple=i686-apple-watchos -Wno-objc-root-class %s
+// RUN: %clang_cc1 -verify -DALLOW -DOTHER -triple=i686-apple-tvos -Wno-objc-root-class %s
+
+// RUN: %clang_cc1 -verify -DALLOW -DOTHER -triple=x86_64-apple-macosx10.10 -Wno-objc-root-class %s
+
+// rdar://21662309
+
+typedef __attribute__((__ext_vector_type__(3))) float float3;
+
+typedef float __m128 __attribute__((__vector_size__(16)));
+
+struct Aggregate { __m128 v; };
+struct AggregateFloat { float v; };
+
+#define AVAILABLE_MACOS_10_10 __attribute__((availability(macos, introduced = 10.10)))
+#define AVAILABLE_MACOS_10_11 __attribute__((availability(macos, introduced = 10.11)))
+
+#define AVAILABLE_IOS_8 __attribute__((availability(ios, introduced = 8.0)))
+#define AVAILABLE_IOS_9 __attribute__((availability(ios, introduced = 9.0)))
+
+@interface VectorMethods
+
+-(void)takeVector:(float3)v; // there should be no diagnostic at declaration
+-(void)takeM128:(__m128)v;
+
+@end
+
+@implementation VectorMethods
+
+#ifndef ALLOW
+
+-(void)takeVector:(float3)v {
+#ifdef MAC
+  // expected-error@-2 {{'float3' (vector of 3 'float' values) parameter type is unsupported; support for vector types for this target is introduced in macOS 10.11}}
+#else
+  // expected-error@-4 {{'float3' (vector of 3 'float' values) parameter type is unsupported; support for vector types for this target is introduced in iOS 9}}
+#endif
+}
+
+-(float3)retVector { // expected-error {{'float3' (vector of 3 'float' values) return type is unsupported}}
+}
+
+-(void)takeVector2:(float3)v AVAILABLE_MACOS_10_10 { // expected-error {{'float3' (vector of 3 'float' values) parameter type is unsupported}}
+}
+
+-(void)takeVector3:(float3)v AVAILABLE_MACOS_10_11 { // expected-error {{'float3' (vector of 3 'float' values) parameter type is unsupported}}
+}
+
+-(void)takeVector4:(float3)v AVAILABLE_IOS_8 { // expected-error {{'float3' (vector of 3 'float' values) parameter type is unsupported}}
+}
+
+-(void)takeVector5:(float3)v AVAILABLE_IOS_9 { // expected-error {{'float3' (vector of 3 'float' values) parameter type is unsupported}}
+}
+
+- (__m128)retM128 { // expected-error {{'__m128' (vector of 4 'float' values) return type is unsupported}}
+}
+
+- (void)takeM128:(__m128)v { // expected-error {{'__m128' (vector of 4 'float' values) parameter type is unsupported}}
+}
+
+#else
+
+-(void)takeVector:(float3)v {
+}
+
+-(float3)retVector {
+  return 0;
+}
+
+- (__m128)retM128 {
+  __m128 value;
+  return value;
+}
+
+- (void)takeM128:(__m128)v {
+}
+
+-(void)takeVector2:(float3)v AVAILABLE_MACOS_10_10 {
+#ifdef MAC
+// expected-error@-2 {{'float3' (vector of 3 'float' values) parameter type is unsupported}}
+#endif
+}
+
+- (__m128)retM128_2 AVAILABLE_MACOS_10_10 {
+#ifdef MAC
+// expected-error@-2 {{'__m128' (vector of 4 'float' values) return type is unsupported}}
+#endif
+  __m128 value;
+  return value;
+}
+
+-(void)takeVector3:(float3)v AVAILABLE_MACOS_10_11 { // no error
+}
+
+-(void)takeVector4:(float3)v AVAILABLE_IOS_8 {
+#ifdef IOS
+  // expected-error@-2 {{'float3' (vector of 3 'float' values) parameter type is unsupported}}
+#endif
+}
+
+-(void)takeVector5:(float3)v AVAILABLE_IOS_9 { // no error
+}
+
+#ifdef OTHER
+// expected-no-diagnostics
+#endif
+
+#endif
+
+-(void)doStuff:(int)m { // no error
+}
+
+-(struct Aggregate)takesAndRetVectorInAggregate:(struct Aggregate)f { // no error
+  struct Aggregate result;
+  return result;
+}
+
+-(struct AggregateFloat)takesAndRetFloatInAggregate:(struct AggregateFloat)f { // no error
+  struct AggregateFloat result;
+  return result;
+}
+
+
+@end
diff --git a/tools/c-index-test/c-index-test.c b/tools/c-index-test/c-index-test.c
index e8763ffc00ae..1179fbf39113 100644
--- a/tools/c-index-test/c-index-test.c
+++ b/tools/c-index-test/c-index-test.c
@@ -1560,6 +1560,51 @@ static enum CXChildVisitResult PrintTypeDeclaration(CXCursor cursor, CXCursor p,
 }
 
 /******************************************************************************/
+/* Target information testing.                                                */
+/******************************************************************************/
+
+static int print_target_info(int argc, const char **argv) {
+  CXIndex Idx;
+  CXTranslationUnit TU;
+  CXTargetInfo TargetInfo;
+  CXString Triple;
+  const char *FileName;
+  enum CXErrorCode Err;
+  int PointerWidth;
+
+  if (argc == 0) {
+    fprintf(stderr, "No filename specified\n");
+    return 1;
+  }
+
+  FileName = argv[1];
+
+  Idx = clang_createIndex(0, 1);
+  Err = clang_parseTranslationUnit2(Idx, FileName, argv, argc, NULL, 0,
+                                    getDefaultParsingOptions(), &TU);
+  if (Err != CXError_Success) {
+    fprintf(stderr, "Couldn't parse translation unit!\n");
+    describeLibclangFailure(Err);
+    clang_disposeIndex(Idx);
+    return 1;
+  }
+
+  TargetInfo = clang_getTranslationUnitTargetInfo(TU);
+
+  Triple = clang_TargetInfo_getTriple(TargetInfo);
+  printf("TargetTriple: %s\n", clang_getCString(Triple));
+  clang_disposeString(Triple);
+
+  PointerWidth = clang_TargetInfo_getPointerWidth(TargetInfo);
+  printf("PointerWidth: %d\n", PointerWidth);
+
+  clang_TargetInfo_dispose(TargetInfo);
+  clang_disposeTranslationUnit(TU);
+  clang_disposeIndex(Idx);
+  return 0;
+}
+
+/******************************************************************************/
 /* Loading ASTs/source.                                                       */
 /******************************************************************************/
 
@@ -2437,11 +2482,14 @@ static void inspect_print_cursor(CXCursor Cursor) {
            clang_Cursor_getObjCSelectorIndex(Cursor));
   if (clang_Cursor_isDynamicCall(Cursor))
     printf(" Dynamic-call");
-  if (Cursor.kind == CXCursor_ObjCMessageExpr) {
+  if (Cursor.kind == CXCursor_ObjCMessageExpr ||
+      Cursor.kind == CXCursor_MemberRefExpr) {
     CXType T = clang_Cursor_getReceiverType(Cursor);
-    CXString S = clang_getTypeKindSpelling(T.kind);
-    printf(" Receiver-type=%s", clang_getCString(S));
-    clang_disposeString(S);
+    if (T.kind != CXType_Invalid) {
+      CXString S = clang_getTypeKindSpelling(T.kind);
+      printf(" Receiver-type=%s", clang_getCString(S));
+      clang_disposeString(S);
+    }
   }
 
   {
@@ -4298,11 +4346,12 @@ static void print_usage(void) {
     "       c-index-test -test-print-type {<args>}*\n"
     "       c-index-test -test-print-type-size {<args>}*\n"
     "       c-index-test -test-print-bitwidth {<args>}*\n"
+    "       c-index-test -test-print-target-info {<args>}*\n"
     "       c-index-test -test-print-type-declaration {<args>}*\n"
     "       c-index-test -print-usr [<CursorKind> {<args>}]*\n"
-    "       c-index-test -print-usr-file <file>\n"
-    "       c-index-test -write-pch <file> <compiler arguments>\n");
+    "       c-index-test -print-usr-file <file>\n");
   fprintf(stderr,
+    "       c-index-test -write-pch <file> <compiler arguments>\n"
     "       c-index-test -compilation-db [lookup <filename>] database\n");
   fprintf(stderr,
     "       c-index-test -print-build-session-timestamp\n");
@@ -4408,6 +4457,8 @@ int cindextest_main(int argc, const char **argv) {
     return perform_test_load_tu(argv[2], "all", NULL, PrintMangledName, NULL);
   else if (argc > 2 && strcmp(argv[1], "-test-print-manglings") == 0)
     return perform_test_load_tu(argv[2], "all", NULL, PrintManglings, NULL);
+  else if (argc > 2 && strcmp(argv[1], "-test-print-target-info") == 0)
+    return print_target_info(argc - 2, argv + 2);
   else if (argc > 1 && strcmp(argv[1], "-print-usr") == 0) {
     if (argc > 2)
       return print_usrs(argv + 2, argv + argc);
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index 216322b9f936..86f1047dee93 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -26,6 +26,7 @@
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/DiagnosticCategories.h"
 #include "clang/Basic/DiagnosticIDs.h"
+#include "clang/Basic/TargetInfo.h"
 #include "clang/Basic/Version.h"
 #include "clang/Frontend/ASTUnit.h"
 #include "clang/Frontend/CompilerInstance.h"
@@ -3371,7 +3372,10 @@ clang_parseTranslationUnit_Impl(CXIndex CIdx, const char *source_filename,
     Args->push_back("-Xclang");
     Args->push_back("-detailed-preprocessing-record");
   }
-  
+
+  // Suppress any editor placeholder diagnostics.
+  Args->push_back("-fallow-editor-placeholders");
+
   unsigned NumErrors = Diags->getClient()->getNumErrors();
   std::unique_ptr<ASTUnit> ErrUnit;
   // Unless the user specified that they want the preamble on the first parse
@@ -4015,6 +4019,50 @@ CXCursor clang_getTranslationUnitCursor(CXTranslationUnit TU) {
   return MakeCXCursor(CXXUnit->getASTContext().getTranslationUnitDecl(), TU);
 }
 
+CXTargetInfo clang_getTranslationUnitTargetInfo(CXTranslationUnit CTUnit) {
+  if (isNotUsableTU(CTUnit)) {
+    LOG_BAD_TU(CTUnit);
+    return nullptr;
+  }
+
+  CXTargetInfoImpl* impl = new CXTargetInfoImpl();
+  impl->TranslationUnit = CTUnit;
+  return impl;
+}
+
+CXString clang_TargetInfo_getTriple(CXTargetInfo TargetInfo) {
+  if (!TargetInfo)
+    return cxstring::createEmpty();
+
+  CXTranslationUnit CTUnit = TargetInfo->TranslationUnit;
+  assert(!isNotUsableTU(CTUnit) &&
+         "Unexpected unusable translation unit in TargetInfo");
+
+  ASTUnit *CXXUnit = cxtu::getASTUnit(CTUnit);
+  std::string Triple =
+    CXXUnit->getASTContext().getTargetInfo().getTriple().normalize();
+  return cxstring::createDup(Triple);
+}
+
+int clang_TargetInfo_getPointerWidth(CXTargetInfo TargetInfo) {
+  if (!TargetInfo)
+    return -1;
+
+  CXTranslationUnit CTUnit = TargetInfo->TranslationUnit;
+  assert(!isNotUsableTU(CTUnit) &&
+         "Unexpected unusable translation unit in TargetInfo");
+
+  ASTUnit *CXXUnit = cxtu::getASTUnit(CTUnit);
+  return CXXUnit->getASTContext().getTargetInfo().getMaxPointerWidth();
+}
+
+void clang_TargetInfo_dispose(CXTargetInfo TargetInfo) {
+  if (!TargetInfo)
+    return;
+
+  delete TargetInfo;
+}
+
 //===----------------------------------------------------------------------===//
 // CXFile Operations.
 //===----------------------------------------------------------------------===//
diff --git a/tools/libclang/CXCursor.cpp b/tools/libclang/CXCursor.cpp
index c19aa65ac622..fb61249a778f 100644
--- a/tools/libclang/CXCursor.cpp
+++ b/tools/libclang/CXCursor.cpp
@@ -1523,6 +1523,10 @@ int clang_Cursor_isDynamicCall(CXCursor C) {
     return true;
   }
 
+  if (auto *PropRefE = dyn_cast<ObjCPropertyRefExpr>(E)) {
+    return !PropRefE->isSuperReceiver();
+  }
+
   const MemberExpr *ME = nullptr;
   if (isa<MemberExpr>(E))
     ME = cast<MemberExpr>(E);
@@ -1532,7 +1536,9 @@ int clang_Cursor_isDynamicCall(CXCursor C) {
   if (ME) {
     if (const CXXMethodDecl *
           MD = dyn_cast_or_null<CXXMethodDecl>(ME->getMemberDecl()))
-      return MD->isVirtual() && !ME->hasQualifier();
+      return MD->isVirtual() &&
+             ME->performsVirtualDispatch(
+                 cxcursor::getCursorContext(C).getLangOpts());
   }
 
   return 0;
@@ -1547,5 +1553,23 @@ CXType clang_Cursor_getReceiverType(CXCursor C) {
   if (const ObjCMessageExpr *MsgE = dyn_cast_or_null<ObjCMessageExpr>(E))
     return cxtype::MakeCXType(MsgE->getReceiverType(), TU);
 
+  if (auto *PropRefE = dyn_cast<ObjCPropertyRefExpr>(E)) {
+    return cxtype::MakeCXType(
+        PropRefE->getReceiverType(cxcursor::getCursorContext(C)), TU);
+  }
+
+  const MemberExpr *ME = nullptr;
+  if (isa<MemberExpr>(E))
+    ME = cast<MemberExpr>(E);
+  else if (const CallExpr *CE = dyn_cast<CallExpr>(E))
+    ME = dyn_cast_or_null<MemberExpr>(CE->getCallee());
+
+  if (ME) {
+    if (dyn_cast_or_null<CXXMethodDecl>(ME->getMemberDecl())) {
+      auto receiverTy = ME->getBase()->IgnoreImpCasts()->getType();
+      return cxtype::MakeCXType(receiverTy, TU);
+    }
+  }
+
   return cxtype::MakeCXType(QualType(), TU);
 }
diff --git a/tools/libclang/CXTranslationUnit.h b/tools/libclang/CXTranslationUnit.h
index 67c31d2dba4f..ce8469b501af 100644
--- a/tools/libclang/CXTranslationUnit.h
+++ b/tools/libclang/CXTranslationUnit.h
@@ -35,6 +35,10 @@ struct CXTranslationUnitImpl {
   clang::index::CommentToXMLConverter *CommentToXML;
 };
 
+struct CXTargetInfoImpl {
+  CXTranslationUnit TranslationUnit;
+};
+
 namespace clang {
 namespace cxtu {
 
diff --git a/tools/libclang/CXType.cpp b/tools/libclang/CXType.cpp
index fce7ef2c0d86..16e993e2ac01 100644
--- a/tools/libclang/CXType.cpp
+++ b/tools/libclang/CXType.cpp
@@ -147,6 +147,9 @@ static inline CXTranslationUnit GetTU(CXType CT) {
 static Optional<ArrayRef<TemplateArgument>>
 GetTemplateArguments(QualType Type) {
   assert(!Type.isNull());
+  if (const auto *Specialization = Type->getAs<TemplateSpecializationType>())
+    return Specialization->template_arguments();
+
   if (const auto *RecordDecl = Type->getAsCXXRecordDecl()) {
     const auto *TemplateDecl =
       dyn_cast<ClassTemplateSpecializationDecl>(RecordDecl);
@@ -154,9 +157,6 @@ GetTemplateArguments(QualType Type) {
       return TemplateDecl->getTemplateArgs().asArray();
   }
 
-  if (const auto *Specialization = Type->getAs<TemplateSpecializationType>())
-    return Specialization->template_arguments();
-
   return None;
 }
 
diff --git a/tools/libclang/Indexing.cpp b/tools/libclang/Indexing.cpp
index f98b25887973..5312b7c0169c 100644
--- a/tools/libclang/Indexing.cpp
+++ b/tools/libclang/Indexing.cpp
@@ -262,7 +262,8 @@ public:
   /// MacroUndefined - This hook is called whenever a macro #undef is seen.
   /// MI is released immediately following this callback.
   void MacroUndefined(const Token &MacroNameTok,
-                      const MacroDefinition &MD) override {}
+                      const MacroDefinition &MD,
+                      const MacroDirective *UD) override {}
 
   /// MacroExpands - This is called by when a macro invocation is found.
   void MacroExpands(const Token &MacroNameTok, const MacroDefinition &MD,
diff --git a/tools/libclang/libclang.exports b/tools/libclang/libclang.exports
index 38ecedae3cd4..895dd804b008 100644
--- a/tools/libclang/libclang.exports
+++ b/tools/libclang/libclang.exports
@@ -79,6 +79,9 @@ clang_TParamCommandComment_getParamName
 clang_TParamCommandComment_isParamPositionValid
 clang_TParamCommandComment_getDepth
 clang_TParamCommandComment_getIndex
+clang_TargetInfo_dispose
+clang_TargetInfo_getPointerWidth
+clang_TargetInfo_getTriple
 clang_Type_getAlignOf
 clang_Type_getClassType
 clang_Type_getSizeOf
@@ -250,6 +253,7 @@ clang_getTokenLocation
 clang_getTokenSpelling
 clang_getTranslationUnitCursor
 clang_getTranslationUnitSpelling
+clang_getTranslationUnitTargetInfo
 clang_getTypeDeclaration
 clang_getTypeKindSpelling
 clang_getTypeSpelling
diff --git a/unittests/Basic/SourceManagerTest.cpp b/unittests/Basic/SourceManagerTest.cpp
index dddc3f98662d..aa15e16b851f 100644
--- a/unittests/Basic/SourceManagerTest.cpp
+++ b/unittests/Basic/SourceManagerTest.cpp
@@ -249,12 +249,18 @@ TEST_F(SourceManagerTest, getMacroArgExpandedLocation) {
 namespace {
 
 struct MacroAction {
+  enum Kind { kExpansion, kDefinition, kUnDefinition};
+
   SourceLocation Loc;
   std::string Name;
-  bool isDefinition; // if false, it is expansion.
-  
-  MacroAction(SourceLocation Loc, StringRef Name, bool isDefinition)
-    : Loc(Loc), Name(Name), isDefinition(isDefinition) { }
+  unsigned MAKind : 3;
+
+  MacroAction(SourceLocation Loc, StringRef Name, unsigned K)
+    : Loc(Loc), Name(Name), MAKind(K) { }
+
+  bool isExpansion() const { return MAKind == kExpansion; }
+  bool isDefinition() const { return MAKind & kDefinition; }
+  bool isUnDefinition() const { return MAKind & kUnDefinition; }
 };
 
 class MacroTracker : public PPCallbacks {
@@ -267,13 +273,22 @@ public:
                     const MacroDirective *MD) override {
     Macros.push_back(MacroAction(MD->getLocation(),
                                  MacroNameTok.getIdentifierInfo()->getName(),
-                                 true));
+                                 MacroAction::kDefinition));
+  }
+  void MacroUndefined(const Token &MacroNameTok,
+                      const MacroDefinition &MD,
+                      const MacroDirective  *UD) override {
+    Macros.push_back(
+        MacroAction(UD ? UD->getLocation() : SourceLocation(),
+                    MacroNameTok.getIdentifierInfo()->getName(),
+                    UD ? MacroAction::kDefinition | MacroAction::kUnDefinition
+                       : MacroAction::kUnDefinition));
   }
   void MacroExpands(const Token &MacroNameTok, const MacroDefinition &MD,
                     SourceRange Range, const MacroArgs *Args) override {
     Macros.push_back(MacroAction(MacroNameTok.getLocation(),
                                  MacroNameTok.getIdentifierInfo()->getName(),
-                                 false));
+                                 MacroAction::kExpansion));
   }
 };
 
@@ -281,7 +296,10 @@ public:
 
 TEST_F(SourceManagerTest, isBeforeInTranslationUnitWithMacroInInclude) {
   const char *header =
-    "#define MACRO_IN_INCLUDE 0\n";
+    "#define MACRO_IN_INCLUDE 0\n"
+    "#define MACRO_DEFINED\n"
+    "#undef MACRO_DEFINED\n"
+    "#undef MACRO_UNDEFINED\n";
 
   const char *main =
     "#define M(x) x\n"
@@ -327,34 +345,46 @@ TEST_F(SourceManagerTest, isBeforeInTranslationUnitWithMacroInInclude) {
   // Make sure we got the tokens that we expected.
   ASSERT_EQ(0U, toks.size());
 
-  ASSERT_EQ(9U, Macros.size());
+  ASSERT_EQ(15U, Macros.size());
   // #define M(x) x
-  ASSERT_TRUE(Macros[0].isDefinition);
+  ASSERT_TRUE(Macros[0].isDefinition());
   ASSERT_EQ("M", Macros[0].Name);
   // #define INC "/test-header.h"
-  ASSERT_TRUE(Macros[1].isDefinition);
+  ASSERT_TRUE(Macros[1].isDefinition());
   ASSERT_EQ("INC", Macros[1].Name);
   // M expansion in #include M(INC)
-  ASSERT_FALSE(Macros[2].isDefinition);
+  ASSERT_FALSE(Macros[2].isDefinition());
   ASSERT_EQ("M", Macros[2].Name);
   // INC expansion in #include M(INC)
-  ASSERT_FALSE(Macros[3].isDefinition);
+  ASSERT_TRUE(Macros[3].isExpansion());
   ASSERT_EQ("INC", Macros[3].Name);
   // #define MACRO_IN_INCLUDE 0
-  ASSERT_TRUE(Macros[4].isDefinition);
+  ASSERT_TRUE(Macros[4].isDefinition());
   ASSERT_EQ("MACRO_IN_INCLUDE", Macros[4].Name);
+  // #define MACRO_DEFINED
+  ASSERT_TRUE(Macros[5].isDefinition());
+  ASSERT_FALSE(Macros[5].isUnDefinition());
+  ASSERT_EQ("MACRO_DEFINED", Macros[5].Name);
+  // #undef MACRO_DEFINED
+  ASSERT_TRUE(Macros[6].isDefinition());
+  ASSERT_TRUE(Macros[6].isUnDefinition());
+  ASSERT_EQ("MACRO_DEFINED", Macros[6].Name);
+  // #undef MACRO_UNDEFINED
+  ASSERT_FALSE(Macros[7].isDefinition());
+  ASSERT_TRUE(Macros[7].isUnDefinition());
+  ASSERT_EQ("MACRO_UNDEFINED", Macros[7].Name);
   // #define INC2 </test-header.h>
-  ASSERT_TRUE(Macros[5].isDefinition);
-  ASSERT_EQ("INC2", Macros[5].Name);
+  ASSERT_TRUE(Macros[8].isDefinition());
+  ASSERT_EQ("INC2", Macros[8].Name);
   // M expansion in #include M(INC2)
-  ASSERT_FALSE(Macros[6].isDefinition);
-  ASSERT_EQ("M", Macros[6].Name);
+  ASSERT_FALSE(Macros[9].isDefinition());
+  ASSERT_EQ("M", Macros[9].Name);
   // INC2 expansion in #include M(INC2)
-  ASSERT_FALSE(Macros[7].isDefinition);
-  ASSERT_EQ("INC2", Macros[7].Name);
+  ASSERT_TRUE(Macros[10].isExpansion());
+  ASSERT_EQ("INC2", Macros[10].Name);
   // #define MACRO_IN_INCLUDE 0
-  ASSERT_TRUE(Macros[8].isDefinition);
-  ASSERT_EQ("MACRO_IN_INCLUDE", Macros[8].Name);
+  ASSERT_TRUE(Macros[11].isDefinition());
+  ASSERT_EQ("MACRO_IN_INCLUDE", Macros[11].Name);
 
   // The INC expansion in #include M(INC) comes before the first
   // MACRO_IN_INCLUDE definition of the included file.
@@ -362,7 +392,7 @@ TEST_F(SourceManagerTest, isBeforeInTranslationUnitWithMacroInInclude) {
 
   // The INC2 expansion in #include M(INC2) comes before the second
   // MACRO_IN_INCLUDE definition of the included file.
-  EXPECT_TRUE(SourceMgr.isBeforeInTranslationUnit(Macros[7].Loc, Macros[8].Loc));
+  EXPECT_TRUE(SourceMgr.isBeforeInTranslationUnit(Macros[10].Loc, Macros[11].Loc));
 }
 
 #endif
diff --git a/unittests/Format/FormatTestJS.cpp b/unittests/Format/FormatTestJS.cpp
index 7886c4fe27ad..eda9e0a31da4 100644
--- a/unittests/Format/FormatTestJS.cpp
+++ b/unittests/Format/FormatTestJS.cpp
@@ -485,6 +485,20 @@ TEST_F(FormatTestJS, AsyncFunctions) {
                "  let x = 1;\n"
                "  return fetch(x);\n"
                "}");
+  verifyFormat("async function f() {\n"
+               "  return 1;\n"
+               "}\n"
+               "\n"
+               "function a() {\n"
+               "  return 1;\n"
+               "}\n",
+               "  async   function f() {\n"
+               "   return 1;\n"
+               "}\n"
+               "\n"
+               "   function a() {\n"
+               "  return   1;\n"
+               "}  \n");
   verifyFormat("async function* f() {\n"
                "  yield fetch(x);\n"
                "}");
@@ -492,6 +506,9 @@ TEST_F(FormatTestJS, AsyncFunctions) {
                "  return fetch(x);\n"
                "}");
   verifyFormat("let x = async () => f();");
+  verifyFormat("let x = async function() {\n"
+               "  f();\n"
+               "};");
   verifyFormat("let x = async();");
   verifyFormat("class X {\n"
                "  async asyncMethod() {\n"
diff --git a/unittests/Frontend/CodeGenActionTest.cpp b/unittests/Frontend/CodeGenActionTest.cpp
index 1d2a50c8bc20..d90c2bce2f6e 100644
--- a/unittests/Frontend/CodeGenActionTest.cpp
+++ b/unittests/Frontend/CodeGenActionTest.cpp
@@ -46,7 +46,7 @@ TEST(CodeGenTest, TestNullCodeGen) {
       "test.cc",
       MemoryBuffer::getMemBuffer("").release());
   Invocation->getFrontendOpts().Inputs.push_back(
-      FrontendInputFile("test.cc", IK_CXX));
+      FrontendInputFile("test.cc", InputKind::CXX));
   Invocation->getFrontendOpts().ProgramAction = EmitLLVM;
   Invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
   CompilerInstance Compiler;
diff --git a/unittests/Frontend/FrontendActionTest.cpp b/unittests/Frontend/FrontendActionTest.cpp
index dd6be5fd4b98..68181c705ce8 100644
--- a/unittests/Frontend/FrontendActionTest.cpp
+++ b/unittests/Frontend/FrontendActionTest.cpp
@@ -83,8 +83,8 @@ TEST(ASTFrontendAction, Sanity) {
   invocation->getPreprocessorOpts().addRemappedFile(
       "test.cc",
       MemoryBuffer::getMemBuffer("int main() { float x; }").release());
-  invocation->getFrontendOpts().Inputs.push_back(FrontendInputFile("test.cc",
-                                                                   IK_CXX));
+  invocation->getFrontendOpts().Inputs.push_back(
+      FrontendInputFile("test.cc", InputKind::CXX));
   invocation->getFrontendOpts().ProgramAction = frontend::ParseSyntaxOnly;
   invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
   CompilerInstance compiler;
@@ -103,8 +103,8 @@ TEST(ASTFrontendAction, IncrementalParsing) {
   invocation->getPreprocessorOpts().addRemappedFile(
       "test.cc",
       MemoryBuffer::getMemBuffer("int main() { float x; }").release());
-  invocation->getFrontendOpts().Inputs.push_back(FrontendInputFile("test.cc",
-                                                                   IK_CXX));
+  invocation->getFrontendOpts().Inputs.push_back(
+      FrontendInputFile("test.cc", InputKind::CXX));
   invocation->getFrontendOpts().ProgramAction = frontend::ParseSyntaxOnly;
   invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
   CompilerInstance compiler;
@@ -130,8 +130,8 @@ TEST(ASTFrontendAction, LateTemplateIncrementalParsing) {
       "  B(B const& b): A<T>(b.data) {}\n"
       "};\n"
       "B<char> c() { return B<char>(); }\n").release());
-  invocation->getFrontendOpts().Inputs.push_back(FrontendInputFile("test.cc",
-                                                                   IK_CXX));
+  invocation->getFrontendOpts().Inputs.push_back(
+      FrontendInputFile("test.cc", InputKind::CXX));
   invocation->getFrontendOpts().ProgramAction = frontend::ParseSyntaxOnly;
   invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
   CompilerInstance compiler;
@@ -177,7 +177,7 @@ TEST(PreprocessorFrontendAction, EndSourceFile) {
       "test.cc",
       MemoryBuffer::getMemBuffer("int main() { float x; }").release());
   Invocation->getFrontendOpts().Inputs.push_back(
-      FrontendInputFile("test.cc", IK_CXX));
+      FrontendInputFile("test.cc", InputKind::CXX));
   Invocation->getFrontendOpts().ProgramAction = frontend::ParseSyntaxOnly;
   Invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
   CompilerInstance Compiler;
@@ -238,7 +238,7 @@ TEST(ASTFrontendAction, ExternalSemaSource) {
                                             "int main() { foo(); }")
                      .release());
   Invocation->getFrontendOpts().Inputs.push_back(
-      FrontendInputFile("test.cc", IK_CXX));
+      FrontendInputFile("test.cc", InputKind::CXX));
   Invocation->getFrontendOpts().ProgramAction = frontend::ParseSyntaxOnly;
   Invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
   CompilerInstance Compiler;
diff --git a/utils/TableGen/ClangAttrEmitter.cpp b/utils/TableGen/ClangAttrEmitter.cpp
index 981445675343..7efc9bccdc5c 100644
--- a/utils/TableGen/ClangAttrEmitter.cpp
+++ b/utils/TableGen/ClangAttrEmitter.cpp
@@ -1670,7 +1670,7 @@ PragmaClangAttributeSupport::PragmaClangAttributeSupport(
       Records.getAllDerivedDefinitions("AttrSubjectMatcherRule");
   auto MapFromSubjectsToRules = [this](const Record *SubjectContainer,
                                        const Record *MetaSubject,
-                                       const Record *Constraint = nullptr) {
+                                       const Record *Constraint) {
     Rules.emplace_back(MetaSubject, Constraint);
     std::vector<Record *> ApplicableSubjects =
         SubjectContainer->getValueAsListOfDefs("Subjects");
@@ -1688,7 +1688,7 @@ PragmaClangAttributeSupport::PragmaClangAttributeSupport(
     }
   };
   for (const auto *MetaSubject : MetaSubjects) {
-    MapFromSubjectsToRules(MetaSubject, MetaSubject);
+    MapFromSubjectsToRules(MetaSubject, MetaSubject, /*Constraints=*/nullptr);
     std::vector<Record *> Constraints =
         MetaSubject->getValueAsListOfDefs("Constraints");
     for (const auto *Constraint : Constraints)