Modules: Code generation of enum constants for merged enum definitions

Found in a bootstrap of LLVM with implicit modules, resulting in a
deadlock of some Orc unit tests with libstdc++ 8.1. An enum was used as
part of the implementation of std::recursive_mutex and this bug resulted
in the constant initialization of zero instead of the desired non-zero
value. => Badness.

Richard Smith tells me neither of these fields are necessarily canonical
& so using declaresSamEntity is the right solution here (rather than
changing both of these Fields to be canonical by construction/from their
source)

llvm-svn: 361428

1 files changed, 1 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index caa327c19a4..c8dd236e957 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -476,7 +476,7 @@ bool ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD,
   for (RecordDecl::field_iterator Field = RD->field_begin(),
        FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) {
     // If this is a union, skip all the fields that aren't being initialized.
-    if (RD->isUnion() && Val.getUnionField() != *Field)
+    if (RD->isUnion() && !declaresSameEntity(Val.getUnionField(), *Field))
       continue;
 
     // Don't emit anonymous bitfields, they just affect layout.