Hi Miles, * Miles Bader wrote on Mon, Nov 01, 2010 at 05:33:13AM CET: > I want to check whether the compiler is giving a warning (about an > unrecognized command-line option). > > Since the compilation still succeeds, AC_COMPILE_IFELSE doesn't do the > job... > > e.g.: > > $ g++ -o /dev/null -catfood -c /tmp/s.cc ; echo $? > g++: unrecognized option '-catfood' > 0 First, please complain to the compiler vendor (whoever is responsible for the behavior). FWIW, I can reproduce with Debian GCC 4.3.5 but not with upstream FSF GCC from SVN. Then, dealing with such behavior is tricky in general. You can use AC_LANG_WERROR, but it has problems if the compiler is verbose by default. Libtool has a couple of macros that test a compiler without and with some flag and compare output of the two, but even that is of limited reliability if the "normal" part of the output is noisy. It's a mess. Cheers, Ralf _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
