Make the odr-use logic work correctly for constant-expressions. PR12006.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151699 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 12 insertions, 0 deletions

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 30a02b2953..5a2b2dc7e9 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -10023,6 +10023,18 @@ void Sema::UpdateMarkingForLValueToRValue(Expr *E) {
   MaybeODRUseExprs.erase(E->IgnoreParens());
 }
 
+ExprResult Sema::ActOnConstantExpression(ExprResult Res) {
+  if (!Res.isUsable())
+    return Res;
+
+  // If a constant-expression is a reference to a variable where we delay
+  // deciding whether it is an odr-use, just assume we will apply the
+  // lvalue-to-rvalue conversion.  In the one case where this doesn't happen
+  // (a non-type template argument), we have special handling anyway.
+  UpdateMarkingForLValueToRValue(Res.get());
+  return Res;
+}
+
 void Sema::CleanupVarDeclMarking() {
   for (llvm::SmallPtrSetIterator<Expr*> i = MaybeODRUseExprs.begin(),
                                         e = MaybeODRUseExprs.end();