zlib update for gdb/binutils

[Joel Brobecker]

> >  - as noted in another mail, you synced GCC's configure.ac, introducing
> >    a build failure with srcdir == builddir builds.  With GCC these
> >    are discouraged, not sure about the status in gdb/binutils.
> 
> In theory it is allowed.  But in practice it is discouraged.
> 
> >  - Please could you apply the GCC r244762 changes to the binutils/gdb
> >    tree as well?
> 
> In fact we were missing quite a few changes to configure.ac, and
> Makefile.def and Makefile.tpl.  So I have checked in a patch to update
> all of these.

Thanks, Nick!

Regarding srcdir == builddir, I agree as well. The problem is that
we have to consider the source packaging as well. I don't know it
well enough right now to tell you whether it would work out-of-tree
or not. After all, you're trying to create a package of the sources,
which includes the files that were checked in the repository, but
also some files that are generated by the source-package process.
I wouldn't want to be missing some files by doing it out of tree...
Maybe there is already a way. If there was, I wouldn't mind taking
the approach where srcdir == builddir is no longer supported. This
would allow some simplifications, particularly in the testsuite
area, I believe.

-- 
Joel