diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index 18b2d75..0a2934b 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -1153,6 +1153,10 @@
       return TemplateArgument();
     return TemplateArgument(E.takeAs<Expr>());
   }
+  
+  case TemplateArgument::Pack:
+    assert(0 && "FIXME: Implement!");
+    break;
   }
 
   assert(false && "Unhandled template argument kind");