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diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst index b11960f7df33..c6dc6aa8ba70 100644 --- a/docs/ReleaseNotes.rst +++ b/docs/ReleaseNotes.rst @@ -1,6 +1,6 @@ -======================= -Clang 3.6 Release Notes -======================= +===================================== +Clang 3.7 (In-Progress) Release Notes +===================================== .. contents:: :local: @@ -8,16 +8,22 @@ Clang 3.6 Release Notes Written by the `LLVM Team <http://llvm.org/>`_ +.. warning:: + + These are in-progress notes for the upcoming Clang 3.7 release. You may + prefer the `Clang 3.6 Release Notes + <http://llvm.org/releases/3.6.0/tools/clang/docs/ReleaseNotes.html>`_. + Introduction ============ This document contains the release notes for the Clang C/C++/Objective-C -frontend, part of the LLVM Compiler Infrastructure, release 3.6. Here we +frontend, part of the LLVM Compiler Infrastructure, release 3.7. Here we describe the status of Clang in some detail, including major improvements from the previous release and new feature work. For the general LLVM release notes, see `the LLVM -documentation <http://llvm.org/releases/3.6.0/docs/ReleaseNotes.html>`_. -All LLVM releases may be downloaded from the `LLVM releases web +documentation <http://llvm.org/docs/ReleaseNotes.html>`_. All LLVM +releases may be downloaded from the `LLVM releases web site <http://llvm.org/releases/>`_. For more information about Clang or LLVM, including information about @@ -25,7 +31,12 @@ the latest release, please check out the main please see the `Clang Web Site <http://clang.llvm.org>`_ or the `LLVM Web Site <http://llvm.org>`_. -What's New in Clang 3.6? +Note that if you are reading this file from a Subversion checkout or the +main Clang web page, this document applies to the *next* release, not +the current one. To see the release notes for a specific release, please +see the `releases page <http://llvm.org/releases/>`_. + +What's New in Clang 3.7? ======================== Some of the major new features and improvements to Clang are listed @@ -36,171 +47,116 @@ sections with improvements to Clang's support for those languages. Major New Features ------------------ -- The __has_attribute built-in macro no longer queries for attributes across - multiple attribute syntaxes (GNU, C++11, __declspec, etc). Instead, it only - queries GNU-style attributes. With the addition of __has_cpp_attribute and - __has_declspec_attribute, this allows for more precise coverage of attribute - syntax querying. - -- clang-format now supports formatting Java code. - +- Use of the ``__declspec`` language extension for declaration attributes now + requires passing the -fms-extensions or -fborland compiler flag. This language + extension is also enabled when compiling CUDA code, but its use should be + viewed as an implementation detail that is subject to change. Improvements to Clang's diagnostics ------------------------------------ +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Clang's diagnostics are constantly being improved to catch more issues, explain them more clearly, and provide more accurate source information about them. The improvements since the 3.5 release include: -- Smarter typo correction. Clang now tries a bit harder to give a usable - suggestion in more cases, and can now successfully recover in more - situations where the suggestion changes how an expression is parsed. - +- ... New Compiler Flags ------------------ -The ``-fpic`` option now uses small pic on PowerPC. +The sized deallocation feature of C++14 is now controlled by the +``-fsized-deallocation`` flag. This feature relies on library support that +isn't yet widely deployed, so the user must supply an extra flag to get the +extra functionality. - -The __EXCEPTIONS macro ----------------------- -``__EXCEPTIONS`` is now defined when landing pads are emitted, not when -C++ exceptions are enabled. The two can be different in Objective-C files: -If C++ exceptions are disabled but Objective-C exceptions are enabled, -landing pads will be emitted. Clang 3.6 is switching the behavior of -``__EXCEPTIONS``. Clang 3.5 confusingly changed the behavior of -``has_feature(cxx_exceptions)``, which used to be set if landing pads were -emitted, but is now set if C++ exceptions are enabled. So there are 3 cases: - -Clang before 3.5: - ``__EXCEPTIONS`` is set if C++ exceptions are enabled, ``cxx_exceptions`` - enabled if C++ or ObjC exceptions are enabled - -Clang 3.5: - ``__EXCEPTIONS`` is set if C++ exceptions are enabled, ``cxx_exceptions`` - enabled if C++ exceptions are enabled - -Clang 3.6: - ``__EXCEPTIONS`` is set if C++ or ObjC exceptions are enabled, - ``cxx_exceptions`` enabled if C++ exceptions are enabled - -To reliably test if C++ exceptions are enabled, use -``__EXCEPTIONS && __has_feature(cxx_exceptions)``, else things won't work in -all versions of Clang in Objective-C++ files. +The option .... New Pragmas in Clang ----------------------- -Clang now supports the `#pragma unroll` and `#pragma nounroll` directives to -specify loop unrolling optimization hints. Placed just prior to the desired -loop, `#pragma unroll` directs the loop unroller to attempt to fully unroll the -loop. The pragma may also be specified with a positive integer parameter -indicating the desired unroll count: `#pragma unroll _value_`. The unroll count -parameter can be optionally enclosed in parentheses. The directive `#pragma -nounroll` indicates that the loop should not be unrolled. These unrolling hints -may also be expressed using the `#pragma clang loop` directive. See the Clang -`language extensions -<http://clang.llvm.org/docs/LanguageExtensions.html#extensions-for-loop-hint-optimizations>`_ -for details. +Clang now supports the ... Windows Support --------------- -- Many, many bug fixes. - -- Clang can now self-host using the ``msvc`` environment on x86 and x64 - Windows. This means that Microsoft C++ ABI is more or less feature-complete, - minus exception support. - -- Added more MSVC compatibility hacks, such as allowing more lookup into - dependent bases of class templates when there is a known template pattern. - As a result, applications using Active Template Library (ATL) or Windows - Runtime Library (WRL) headers should compile correctly. - -- Added support for the Visual C++ ``__super`` keyword. - -- Added support for MSVC's ``__vectorcall`` calling convention, which is used - in the upcoming Visual Studio 2015 STL. - -- Added basic support for DWARF debug information in COFF files. +Clang's support for building native Windows programs ... C Language Changes in Clang --------------------------- -- The default language mode for C compilations with Clang has been changed from - C99 with GNU extensions to C11 with GNU extensions. C11 is largely - backwards-compatible with C99, but if you want to restore the former behavior - you can do so with the `-std=gnu99` flag. +... C11 Feature Support ^^^^^^^^^^^^^^^^^^^ -- Clang now provides an implementation of the standard C11 header `<stdatomic.h>`. +... C++ Language Changes in Clang ----------------------------- -- An `upcoming change to C++ <http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3922.html>_` - changes the semantics of certain deductions of `auto` from a braced initializer - list. Following the intent of the C++ committee, this change will be applied to - our C++11 and C++14 modes as well as our experimental C++17 mode. Clang 3.6 - does not yet implement this change, but to provide a transition period, it - warns on constructs whose meaning will change. The fix in all cases is to - add an `=` prior to the left brace. +- ... -- Clang now supports putting identical constructors and destructors in - the C5/D5 comdat, reducing code duplication. +C++11 Feature Support +^^^^^^^^^^^^^^^^^^^^^ -- Clang will put individual ``.init_array/.ctors`` sections in - comdats, reducing code duplication and speeding up startup. +... +Objective-C Language Changes in Clang +------------------------------------- -C++17 Feature Support -^^^^^^^^^^^^^^^^^^^^^ +... -Clang has experimental support for some proposed C++1z (tentatively, C++17) -features. This support can be enabled using the `-std=c++1z` flag. +OpenCL C Language Changes in Clang +---------------------------------- -New in Clang 3.6 is support for: +... -- Fold expressions +Internal API Changes +-------------------- -- `u8` character literals +These are major API changes that have happened since the 3.6 release of +Clang. If upgrading an external codebase that uses Clang as a library, +this section should help get you past the largest hurdles of upgrading. -- Nested namespace definitions: `namespace A::B { ... }` as a shorthand for - `namespace A { namespace B { ... } }` +- Some of the `PPCallbacks` interface now deals in `MacroDefinition` + objects instead of `MacroDirective` objects. This allows preserving + full information on macros imported from modules. -- Attributes for namespaces and enumerators +- `clang-c/Index.h` no longer `#include`\s `clang-c/Documentation.h`. + You now need to explicitly `#include "clang-c/Documentation.h"` if + you use the libclang documentation API. -- Constant evaluation for all non-type template arguments +libclang +-------- -Note that these features may be changed or removed in future Clang releases -without notice. +... -Support for `for (identifier : range)` as a synonym for -`for (auto &&identifier : range)` has been removed as it is no longer currently -considered for C++17. +Static Analyzer +--------------- + +... + +Core Analysis Improvements +========================== -For more details on C++ feature support, see -`the C++ status page <http://clang.llvm.org/cxx_status.html>`_. +- ... +New Issues Found +================ + +- ... + +Python Binding Changes +---------------------- -OpenMP Language Changes in Clang --------------------------------- +The following methods have been added: -Clang 3.6 contains codegen for many individual OpenMP pragmas, but combinations are not completed yet. -We plan to continue codegen code drop aiming for completion in 3.7. Please see this link for up-to-date -`status <https://github.com/clang-omp/clang/wiki/Status-of-supported-OpenMP-constructs>_`. -LLVM's OpenMP runtime library, originally developed by Intel, has been modified to work on ARM, PowerPC, -as well as X86. The Runtime Library's compatibility with GCC 4.9 is improved -- missed entry points added, barrier and fork/join code improved, one more type of barrier enabled. -Support for ppc64le architecture is now available and automatically detected when using cmake system. -Using makefile the new "ppc64le" arch type is available. -Contributors to this work include AMD, Argonne National Lab., IBM, Intel, Texas Instruments, University of Houston and many others. +- ... +Significant Known Problems +========================== Additional Information ====================== |