[CodeGen] Fix an assert in CodeGenFunction::EmitFunctionEpilog

The assert is triggered because isObjCRetainableType() is called on the
canonicalized return type that has been stripped of the typedefs and
attributes attached to it. To fix this assert, this commit gets the
original return type from CurCodeDecl or BlockInfo and uses it instead
of the canoicalized type.

rdar://problem/24470031

Differential Revision: http://reviews.llvm.org/D16914

llvm-svn: 261151

1 files changed, 19 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 61b2fe78db7..281292f764c 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -14,6 +14,7 @@
 
 #include "CGCall.h"
 #include "ABIInfo.h"
+#include "CGBlocks.h"
 #include "CGCXXABI.h"
 #include "CGCleanup.h"
 #include "CodeGenFunction.h"
@@ -2462,9 +2463,26 @@ void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI,
     // In ARC, end functions that return a retainable type with a call
     // to objc_autoreleaseReturnValue.
     if (AutoreleaseResult) {
+#ifndef NDEBUG
+      // Type::isObjCRetainabletype has to be called on a QualType that hasn't
+      // been stripped of the typedefs, so we cannot use RetTy here. Get the
+      // original return type of FunctionDecl, CurCodeDecl, and BlockDecl from
+      // CurCodeDecl or BlockInfo.
+      QualType RT;
+
+      if (auto *FD = dyn_cast<FunctionDecl>(CurCodeDecl))
+        RT = FD->getReturnType();
+      else if (auto *MD = dyn_cast<ObjCMethodDecl>(CurCodeDecl))
+        RT = MD->getReturnType();
+      else if (isa<BlockDecl>(CurCodeDecl))
+        RT = BlockInfo->BlockExpression->getFunctionType()->getReturnType();
+      else
+        llvm_unreachable("Unexpected function/method type");
+
       assert(getLangOpts().ObjCAutoRefCount &&
              !FI.isReturnsRetained() &&
-             RetTy->isObjCRetainableType());
+             RT->isObjCRetainableType());
+#endif
       RV = emitAutoreleaseOfResult(*this, RV);
     }