RFC: Changing AC_PROG_CC to AC_PROG_CC_C99 in top level configure

[Tom Tromey]

>>>>> "Simon" == Simon Marchi via Gcc-patches <gcc-patches@gcc.gnu.org> writes:

Simon> For GDB, it's not supported to run gdb/configure directly, you need to
Simon> use the top-level configure.  Is it supported from some of the other
Simon> projects in the repo?

It can be done sometimes but I think it isn't really a scenario worth
worrying about.  Normally this kind of thing is only doable for sources
that are already independent of the top-level configury -- drop-in stuff
like gmp or libiconv, or roots of the tree like libiberty and gnulib.

Simon> I just tried with ld, it doesn't work since it depends on bfd also being
Simon> built.  I tried with just bfd, it doesn't work (with the default
Simon> configure options at least) because it requires zlib being built.

Yeah, most of the things that are "really" in-tree have dependencies and
can't be built independently of the rest.

Tom