1 files changed, 19 insertions, 8 deletions

diff --git a/lib/Sema/SemaLambda.cpp b/lib/Sema/SemaLambda.cpp
index 0cf4ed7c6081..90a81f4ec452 100644
--- a/lib/Sema/SemaLambda.cpp
+++ b/lib/Sema/SemaLambda.cpp
@@ -617,7 +617,7 @@ void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
   // If it was ever a placeholder, it had to been deduced to DependentTy.
   assert(CSI.ReturnType.isNull() || !CSI.ReturnType->isUndeducedType()); 
 
-  // C++ Core Issue #975, proposed resolution:
+  // C++ core issue 975:
   //   If a lambda-expression does not include a trailing-return-type,
   //   it is as if the trailing-return-type denotes the following type:
   //     - if there are no return statements in the compound-statement,
@@ -631,6 +631,10 @@ void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
   //       same, that common type;
   //     - otherwise, the program is ill-formed.
   //
+  // C++ core issue 1048 additionally removes top-level cv-qualifiers
+  // from the types of returned expressions to match the C++14 auto
+  // deduction rules.
+  //
   // In addition, in blocks in non-C++ modes, if all of the return
   // statements are enumerator-like expressions of some type T, where
   // T has a name for linkage, then we infer the return type of the
@@ -679,7 +683,8 @@ void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
     const ReturnStmt *RS = *I;
     const Expr *RetE = RS->getRetValue();
 
-    QualType ReturnType = (RetE ? RetE->getType() : Context.VoidTy);
+    QualType ReturnType =
+        (RetE ? RetE->getType() : Context.VoidTy).getUnqualifiedType();
     if (Context.hasSameType(ReturnType, CSI.ReturnType))
       continue;
 
@@ -873,7 +878,7 @@ void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
     // We don't do this before C++1y, because we don't support deduced return
     // types there.
     QualType DefaultTypeForNoTrailingReturn =
-        getLangOpts().CPlusPlus1y ? Context.getAutoDeductType()
+        getLangOpts().CPlusPlus14 ? Context.getAutoDeductType()
                                   : Context.DependentTy;
     QualType MethodTy =
         Context.getFunctionType(DefaultTypeForNoTrailingReturn, None, EPI);
@@ -999,7 +1004,7 @@ void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
 
     VarDecl *Var = nullptr;
     if (C->Init.isUsable()) {
-      Diag(C->Loc, getLangOpts().CPlusPlus1y
+      Diag(C->Loc, getLangOpts().CPlusPlus14
                        ? diag::warn_cxx11_compat_init_capture
                        : diag::ext_init_capture);
 
@@ -1049,8 +1054,8 @@ void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
       if (R.empty()) {
         // FIXME: Disable corrections that would add qualification?
         CXXScopeSpec ScopeSpec;
-        DeclFilterCCC<VarDecl> Validator;
-        if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R, Validator))
+        if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R,
+                                llvm::make_unique<DeclFilterCCC<VarDecl>>()))
           continue;
       }
 
@@ -1062,7 +1067,7 @@ void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
     // C++11 [expr.prim.lambda]p8:
     //   An identifier or this shall not appear more than once in a
     //   lambda-capture.
-    if (!CaptureNames.insert(C->Id)) {
+    if (!CaptureNames.insert(C->Id).second) {
       if (Var && LSI->isCaptured(Var)) {
         Diag(C->Loc, diag::err_capture_more_than_once)
             << C->Id << SourceRange(LSI->getCapture(Var).getLocation())
@@ -1414,6 +1419,12 @@ ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
                                                          /*isImplicit=*/true));
         continue;
       }
+      if (From.isVLATypeCapture()) {
+        Captures.push_back(
+            LambdaCapture(From.getLocation(), IsImplicit, LCK_VLAType));
+        CaptureInits.push_back(nullptr);
+        continue;
+      }
 
       VarDecl *Var = From.getVariable();
       LambdaCaptureKind Kind = From.isCopyCapture()? LCK_ByCopy : LCK_ByRef;
@@ -1451,7 +1462,7 @@ ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
     // different machinery.
     // FIXME: Refactor and Merge the return type deduction machinery.
     // FIXME: Assumes current resolution to core issue 975.
-    if (LSI->HasImplicitReturnType && !getLangOpts().CPlusPlus1y) {
+    if (LSI->HasImplicitReturnType && !getLangOpts().CPlusPlus14) {
       deduceClosureReturnType(*LSI);
 
       //   - if there are no return statements in the