At line 40 we AC_DEFINE(HAVE_SELINUX_SELINUX_H,0) http://git.savannah.gnu.org/gitweb/?p=gnulib.git;a=blob;f=m4/selinux-selinux-h.m4;h=fd09b299;hb=HEAD#l40 However that may already defined to 1 which is the case when compiling in -m32 mode but with only the first of these installed:
$ rpm -qf /usr/include/selinux/selinux.h libselinux-devel-2.3-9.fc22.x86_64 libselinux-devel-2.3-9.fc22.i686 In that edge case, -Werror will fail due to the redefinition, thus causing -Werror to not be used in the build. Quite the edge case I know, but I'm not sure how best to avoid. Perhaps we should not use AC_CHECK_HEADERS here, instead going lower level with AC_PREPROC_IFELSE(.. AC_DEFINE ..) ? cheers, Pádraig.
