diff --git a/include/clang/Basic/DiagnosticParseKinds.td b/include/clang/Basic/DiagnosticParseKinds.td
index 865200b..c9eb2ad 100644
--- a/include/clang/Basic/DiagnosticParseKinds.td
+++ b/include/clang/Basic/DiagnosticParseKinds.td
@@ -169,8 +169,6 @@
   "expected member name or ';' after declaration specifiers">;
 def err_function_declared_typedef : Error<
   "function definition declared 'typedef'">;
-def err_iboutletcollection_with_protocol : Error<
-  "invalid argument of iboutletcollection attribute">;
 def err_at_defs_cxx : Error<"@defs is not supported in Objective-C++">;
 def err_at_in_class : Error<"unexpected '@' in member specification">;