--- a/make/autoconf/flags-cflags.m4	Fri May 03 12:33:08 2019 -0400
+++ b/make/autoconf/flags-cflags.m4	Fri May 03 09:34:02 2019 -0700
@@ -219,7 +219,7 @@
           -Wunused-function -Wundef -Wunused-value -Woverloaded-virtual"
       WARNINGS_ENABLE_ALL="-Wall -Wextra -Wformat=2 $WARNINGS_ENABLE_ADDITIONAL"
 
-      DISABLED_WARNINGS="unused-parameter unused"
+      DISABLED_WARNINGS="unknown-warning-option unused-parameter unused"
 
       if test "x$OPENJDK_TARGET_OS" = xmacosx; then
         # missing-method-return-type triggers in JavaNativeFoundation framework