When converting a block pointer to an Objective-C pointer type, extend

the lifetime of the block by copying it to the heap, or else we'll get
a dangling reference because the code working with the non-block-typed
object will not know it needs to copy.

There is some danger here, e.g. with assigning a block literal to an
unsafe variable, but, well, it's an unsafe variable.

llvm-svn: 139451

1 files changed, 5 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 35876d8c319..6741f433660 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -1027,7 +1027,7 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
                           ConvertType(CGF.getContext().getPointerType(DestTy)));
     return EmitLoadOfLValue(CGF.MakeAddrLValue(V, DestTy));
   }
-      
+
   case CK_CPointerToObjCPointerCast:
   case CK_BlockPointerToObjCPointerCast:
   case CK_AnyPointerToBlockPointerCast:
@@ -1124,6 +1124,10 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
     value = CGF.EmitARCRetainAutoreleasedReturnValue(value);
     return CGF.EmitObjCConsumeObject(E->getType(), value);
   }
+  case CK_ObjCExtendBlockObject: {
+    llvm::Value *value = CGF.EmitARCRetainScalarExpr(E);
+    return CGF.EmitObjCConsumeObject(E->getType(), value);
+  }
 
   case CK_FloatingRealToComplex:
   case CK_FloatingComplexCast: