Update comment to accurately reflect what should happen.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161286 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index c604e56..9e3127b 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1537,7 +1537,7 @@
   uint64_t FieldOffset = 0;
   llvm::Value *ElementTypes[2];
   
-  // FIXME: This should probably be a function type instead.
+  // FIXME: This should be a DW_TAG_pointer_to_member type.
   ElementTypes[0] =
     DBuilder.createMemberType(U, "ptr", U, 0,
                               Info.first, Info.second, FieldOffset, 0,