1 files changed, 5 insertions, 0 deletions
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 1df0701ee9..6936539f1c 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -289,6 +289,11 @@ TemplateDeclInstantiator::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
 }
 
 Decl *
+TemplateDeclInstantiator::VisitExternCContextDecl(ExternCContextDecl *D) {
+  llvm_unreachable("extern \"C\" context cannot be instantiated");
+}
+
+Decl *
 TemplateDeclInstantiator::VisitLabelDecl(LabelDecl *D) {
   LabelDecl *Inst = LabelDecl::Create(SemaRef.Context, Owner, D->getLocation(),
                                       D->getIdentifier());