When we can't prove that the target of an aggregate copy is

a complete object, the memcpy needs to use the data size of
the structure instead of its sizeof() value.  Fixes PR12204.

llvm-svn: 153613

1 files changed, 4 insertions, 2 deletions

diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp
index 670167b9590..489386dfa2e 100644
--- a/clang/lib/CodeGen/CGStmt.cpp
+++ b/clang/lib/CodeGen/CGStmt.cpp
@@ -722,7 +722,8 @@ void CodeGenFunction::EmitReturnOfRValue(RValue RV, QualType Ty) {
   if (RV.isScalar()) {
     Builder.CreateStore(RV.getScalarVal(), ReturnValue);
   } else if (RV.isAggregate()) {
-    EmitAggregateCopy(ReturnValue, RV.getAggregateAddr(), Ty);
+    EmitAggregateCopy(ReturnValue, RV.getAggregateAddr(), Ty,
+                      /*volatile*/ false, 0, /*destIsCompleteObject*/ true);
   } else {
     StoreComplexToAddr(RV.getComplexVal(), ReturnValue, false);
   }
@@ -769,7 +770,8 @@ void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) {
     EmitAggExpr(RV, AggValueSlot::forAddr(ReturnValue, Alignment, Qualifiers(),
                                           AggValueSlot::IsDestructed,
                                           AggValueSlot::DoesNotNeedGCBarriers,
-                                          AggValueSlot::IsNotAliased));
+                                          AggValueSlot::IsNotAliased,
+                                          AggValueSlot::IsCompleteObject));
   }
 
   EmitBranchThroughCleanup(ReturnBlock);