diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 322427862f67fc620f5cac3fe7426ff941707419..42de37a4beede007fee2f0d982631ff9f50947eb 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -6639,7 +6639,7 @@ def warn_function_def_in_objc_container : Warning<
 def warn_cast_calling_conv : Warning<
   "cast between incompatible calling conventions '%0' and '%1'; "
   "calls through this pointer may abort at runtime">,
-  InGroup<DiagGroup<"cast-calling-convention">>, DefaultIgnore;
+  InGroup<DiagGroup<"cast-calling-convention">>;
 def note_change_calling_conv_fixit : Note<
   "consider defining %0 with the '%1' calling convention">;
 def warn_bad_function_cast : Warning<