Update comment to accurately reflect what should happen.

llvm-svn: 161286
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index c604e56..9e3127b 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/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,