+dnl If the C compiler is really GCC, enable warnings and
+dnl GCC-specific flags. Bug in glib GStaticMutex prevents
+dnl us from using strict aliasing safely.
+dnl NB: We have to do this after all the function tests
+dnl because '-Werror' tends to break them.
+if test "$GCC" = "yes"; then
+ CFLAGS="$CFLAGS -Wall -Werror -fno-strict-aliasing"
+fi
+