diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index f4653c1..d2e8419 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -134,6 +134,8 @@
   // BuildArrayType. Since we have already checked the size as part of
   // creating the dependent array type in the first place, we know
   // there aren't any errors.
+  // FIXME: Is IntTy big enough? Maybe not, but LongLongTy causes
+  // problems that I have yet to investigate.
   IntegerLiteral ArraySize(T->getSize(), SemaRef.Context.IntTy, Loc);
   return SemaRef.BuildArrayType(ElementType, T->getSizeModifier(), 
                                 &ArraySize, T->getIndexTypeQualifier(),