Re: [PATCH] Simplify the IPA parts of the gdbserver Makefile

["Christian Biesinger via gdb-patches" <gdb-patches@sourceware.org>]

On Tue, Nov 26, 2019 at 2:56 PM Pedro Alves <palves@redhat.com> wrote:
>
> On 11/26/19 8:32 PM, Christian Biesinger wrote:
> >> Currently the IPA uses gnulib headers, but not the function
> >> replacements.  What's the end goal you're after?  Why is this
> >> an improvement?
> >
> > Right. The end goal is
> > https://sourceware.org/ml/gdb-patches/2019-11/msg00922.html -- I want
> > to be able to call safe_strerror from more places, which means the
> > implementation of safe_strerror needs to be able to call glibc's
> > strerror_r. I suppose I could try adding it to UNDO_GNULIB_CFLAGS,
> > maybe, but it seemed less confusing to change it like this.
> So currently strerror_r is replaced by gnulib and you get a link
> error?

Yes, exactly.

> What bothers me is that this moves in the direction of having to
> handle portability ourselves, effectively undoing the benefits
> of gnulib.  It seems to me to walk in the opposite direction of
> the ideal, which would be for the IPA to also use gnulib.
> It doesn't use gnulib today, because the IPA is a shared library,
> so we'd need to link with a build of gnulib built with -fPIC.

Oh, is that the only reason? That seems like it should be fixable
reasonably easily, just build gdbserver's gnulib with -fPIC. And if we
move to a single Gnulib build we can just build all of it with -fPIC,
I would think, not much of a downside. I thought there may be codesize
concerns.

> The UNDO_GNULIB_CFLAGS stuff at least gives us normalized headers
> between gdb / gdbserver / IPA, which for simple header portability
> fixes and defines seems good enough, though not ideal, of course.

OK, I'll update that other patch to use that.

Do you think https://sourceware.org/ml/gdb-patches/2019-11/msg00908.html
is still worth having or should I withdraw that too?

Christian