Hi Eric, [CCing bug-autoconf. This is a reply to <http://lists.gnu.org/archive/html/bug-gnulib/2009-01/msg00247.html>]
> * gnulib-tool (func_dest_tmpfilename, func_create_testdir): Using > obsolete AC_GNU_SOURCE causes out-of-order expansion; avoid it, > and rely solely on gl_USE_SYSTEM_EXTENSIONS. When you are applying such a patch to gnulib, I think you should also deprecate AC_GNU_SOURCE in autoconf. Why? Currently autoconf documents AC_GNU_SOURCE as "This macro is a platform-specific subset of @code{AC_USE_SYSTEM_EXTENSIONS} (@pxref{AC_USE_SYSTEM_EXTENSIONS})." If a user needs only AC_GNU_SOURCE, because of a problem only present in the glibc header files, according to this documentation AC_GNU_SOURCE is his primary choice. But what you discovered is that AC_GNU_SOURCE and AC_USE_SYSTEM_EXTENSIONS don't play well together with each other. Or otherwise, you can fix the conflict between AC_GNU_SOURCE and AC_USE_SYSTEM_EXTENSIONS differently, and then undo the gnulib change. Bruno