diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 0b0efcb..f13bd69 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -1304,6 +1304,9 @@
 Decl *Sema::SubstDecl(Decl *D, DeclContext *Owner,
                       const MultiLevelTemplateArgumentList &TemplateArgs) {
   TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
+  if (D->isInvalidDecl())
+    return 0;
+
   return Instantiator.Visit(D);
 }