http://bugs.winehq.org/show_bug.cgi?id=33521
--- Comment #11 from Dan Kegel dank@kegel.com 2013-06-22 13:17:11 CDT --- Since you're passing a non-default CFLAGS, you can just add that option there. But if you really think the workaround belongs in wine's source tree, configure.ac might be a good place for it, search for "dnl Check for some compiler flags".