5 files changed, 81 insertions, 2 deletions

diff --git a/lib/AST/DeclCXX.cpp b/lib/AST/DeclCXX.cpp
index 5b9ab4ff5c..b5b3f12f5e 100644
--- a/lib/AST/DeclCXX.cpp
+++ b/lib/AST/DeclCXX.cpp
@@ -1759,6 +1759,21 @@ CXXConversionDecl::Create(ASTContext &C, CXXRecordDecl *RD,
                                    EndLocation);
 }
 
+bool CXXConversionDecl::isLambdaToBlockPointerConversion() const {
+  return isImplicit() && getParent()->isLambda() &&
+         getConversionType()->isBlockPointerType();
+}
+
+Expr *CXXConversionDecl::getLambdaToBlockPointerCopyInit() const {
+  assert(isLambdaToBlockPointerConversion());
+  return getASTContext().LambdaBlockPointerInits[this];
+}
+
+void CXXConversionDecl::setLambdaToBlockPointerCopyInit(Expr *Init) {
+  assert(isLambdaToBlockPointerConversion());
+  getASTContext().LambdaBlockPointerInits[this] = Init;
+}
+
 void LinkageSpecDecl::anchor() { }
 
 LinkageSpecDecl *LinkageSpecDecl::Create(ASTContext &C,
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 447a4b4257..66ec800c72 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -9050,7 +9050,60 @@ bool Sema::isImplicitlyDeleted(FunctionDecl *FD) {
          (FD->isDefaulted() || FD->isImplicit()) &&
          isa<CXXMethodDecl>(FD);
 }
-    
+
+void Sema::DefineImplicitLambdaToFunctionPointerConversion(
+       SourceLocation CurrentLocation,
+       CXXConversionDecl *Conv) 
+{
+  Conv->setUsed();
+  
+  ImplicitlyDefinedFunctionScope Scope(*this, Conv);
+  DiagnosticErrorTrap Trap(Diags);
+  
+  // Introduce a bogus body, which IR generation will override anyway.
+  Conv->setBody(new (Context) CompoundStmt(Context, 0, 0, Conv->getLocation(),
+                                           Conv->getLocation()));
+  
+  if (ASTMutationListener *L = getASTMutationListener()) {
+    L->CompletedImplicitDefinition(Conv);
+  }
+}
+
+void Sema::DefineImplicitLambdaToBlockPointerConversion(
+       SourceLocation CurrentLocation,
+       CXXConversionDecl *Conv) 
+{
+  Conv->setUsed();
+  
+  ImplicitlyDefinedFunctionScope Scope(*this, Conv);
+  DiagnosticErrorTrap Trap(Diags);
+  
+  // Copy-initialize the lambda object as needed to capture
+  Expr *This = ActOnCXXThis(CurrentLocation).take();
+  Expr *DerefThis =CreateBuiltinUnaryOp(CurrentLocation, UO_Deref, This).take();
+  ExprResult Init = PerformCopyInitialization(
+                      InitializedEntity::InitializeBlock(CurrentLocation, 
+                                                         DerefThis->getType(), 
+                                                         /*NRVO=*/false),
+                      CurrentLocation, DerefThis);
+  if (!Init.isInvalid())
+    Init = ActOnFinishFullExpr(Init.take());
+  
+  if (!Init.isInvalid())
+    Conv->setLambdaToBlockPointerCopyInit(Init.take());
+  else {
+    Diag(CurrentLocation, diag::note_lambda_to_block_conv);
+  }
+  
+  // Introduce a bogus body, which IR generation will override anyway.
+  Conv->setBody(new (Context) CompoundStmt(Context, 0, 0, Conv->getLocation(),
+                                           Conv->getLocation()));
+  
+  if (ASTMutationListener *L = getASTMutationListener()) {
+    L->CompletedImplicitDefinition(Conv);
+  }
+}
+
 ExprResult
 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
                             CXXConstructorDecl *Constructor,
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index b05f4d5623..7fee518d2c 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -9447,6 +9447,13 @@ void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func) {
         else
           DefineImplicitMoveAssignment(Loc, MethodDecl);
       }
+    } else if (isa<CXXConversionDecl>(MethodDecl) &&
+               MethodDecl->getParent()->isLambda()) {
+      CXXConversionDecl *Conversion = cast<CXXConversionDecl>(MethodDecl);
+      if (Conversion->isLambdaToBlockPointerConversion())
+        DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion);
+      else
+        DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion);
     } else if (MethodDecl->isVirtual())
       MarkVTableUsed(Loc, MethodDecl->getParent());
   }
@@ -10041,7 +10048,7 @@ static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc,
   }
 
   SemaRef.MarkAnyDeclReferenced(Loc, D);
-}
+} 
 
 /// \brief Perform reference-marking and odr-use handling for a
 /// BlockDeclRefExpr.
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 547dc568e7..6e044fd0db 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -1206,6 +1206,8 @@ void ASTDeclReader::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
 void ASTDeclReader::VisitCXXConversionDecl(CXXConversionDecl *D) {
   VisitCXXMethodDecl(D);
   D->IsExplicitSpecified = Record[Idx++];
+  if (D->isLambdaToBlockPointerConversion())
+    D->setLambdaToBlockPointerCopyInit(Reader.ReadExpr(F));
 }
 
 void ASTDeclReader::VisitImportDecl(ImportDecl *D) {
diff --git a/lib/Serialization/ASTWriterDecl.cpp b/lib/Serialization/ASTWriterDecl.cpp
index 7cd2f4ebed..584ff1c144 100644
--- a/lib/Serialization/ASTWriterDecl.cpp
+++ b/lib/Serialization/ASTWriterDecl.cpp
@@ -961,6 +961,8 @@ void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
   VisitCXXMethodDecl(D);
   Record.push_back(D->IsExplicitSpecified);
+  if (D->isLambdaToBlockPointerConversion())
+    Writer.AddStmt(D->getLambdaToBlockPointerCopyInit());
   Code = serialization::DECL_CXX_CONVERSION;
 }