$OpenBSD: patch-configure_ac,v 1.1 2017/09/25 09:16:13 robert Exp $

Index: configure.ac
--- configure.ac.orig
+++ configure.ac
@@ -259,7 +259,7 @@ case "$host" in
         SAVED_CFLAGS="${CFLAGS}"
         CFLAGS="-fvisibility=hidden"
         AC_MSG_CHECKING([for -fvisibility=hidden compiler flag])
-        AC_TRY_COMPILE([], [int main (void) { return 0; }],
+        AC_TRY_COMPILE([], [],
                        AC_MSG_RESULT(yes)
                        enable_fvisibility_hidden=yes,
                        AC_MSG_RESULT(no)
