diff --git a/m4/visibility_hidden.m4 b/m4/visibility_hidden.m4
index 8b6d9e19..bfd74e4b 100644
--- a/m4/visibility_hidden.m4
+++ b/m4/visibility_hidden.m4
@@ -17,6 +17,6 @@ EOF
 		  rm -f conftest.[cs]
 		  ])
    if test $libc_cv_visibility_attribute = yes; then
-     AC_DEFINE(HAVE_VISIBILITY_ATTRIBUTE)
+     AC_DEFINE(HAVE_VISIBILITY_ATTRIBUTE, [], [GCC supports visibility attributes])
    fi
   ])