Re: --with-included-foo={yes,no} and which foo.h to use?

[Paul Eggert]

As it happens, yesterday I updated gnulib regex to use the latest
version from GLIBC.  This is a big deal: it's a 20,000-line patch.
See:

http://lists.gnu.org/archive/html/bug-gnulib/2005-07/msg00041.html

I plan to import this change into coreutils today or tomorrow.

I also found the bug that Charles Levert mentioned.  I fixed it in
gnulib and reported it here for glibc:

http://sources.redhat.com/bugzilla/show_bug.cgi?id=1054

so you don't need to report it.  (I have no response yet from the
glibc regex guru.)

I suggest that grep use gnulib regex rather than importing regex by
hand from glibc.  This will require some changes to the patch that
Charles Levert proposed in
<http://lists.gnu.org/archive/html/bug-grep/2005-07/msg00022.html>.
In particular, regex.m4 needs some significant changes; the version in
Levert's patch is incorrect for glibc's newer code.  Also, one include
file gets moved and one removed, so there's no longer a
lib/posix/regex.h.

Using gnulib will help us all share any such improvements in the build
process.  I have some more changes in the pipeline, but they are all
code/porting cleanups, not bug fixes.

You can use gnulib-tool to import sources from gnulib.  This is item
#2 on grep's TODO list.  Presumably you're going to wait on
gnulib-tool until after the next grep release, but it should get done
eventually; it'll save you some work in the future.