[PATCH v2] <shlib-compat.h>: Support compat_symbol_reference for _ISOMAC

[Florian Weimer]

* H. J. Lu:

> On Tue, Mar 2, 2021 at 1:18 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>>
>> On Tue, Mar 2, 2021 at 1:02 PM Florian Weimer <fweimer@redhat.com> wrote:
>> >
>> > * H. J. Lu:
>> >
>> > > On Tue, Mar 2, 2021 at 12:10 PM Florian Weimer via Libc-alpha
>> > > <libc-alpha@sourceware.org> wrote:
>> > >>
>> > >> This is helpful for testing compat symbols in cases where _ISOMAC
>> > >> is activated implicitly due to -DMODULE_NAME=testsuite and cannot
>> > >> be disabled easily.
>> > >>
>> > >> ---
>> > >> v2: Now actually tested in the situation where I need it.
>> > >>
>> > >
>> > > Any particular tests which need this?
>> >
>> > nptl/tst-cleanup4aux.c will need this once _pthread_cleanup_push,
>> > _pthread_cleanup_pop are compatibility symbols.
>> >
>>
>> Do you just want to link against the older version and nothing else?
>>
>
> Why are these tests OK without your patch?
>
> malloc/tst-mallocstate.c:compat_symbol_reference (libc,
> malloc_get_state, malloc_get_state, GLIBC_2_0);
> malloc/tst-mallocstate.c:compat_symbol_reference (libc,
> malloc_set_state, malloc_set_state, GLIBC_2_0);

tests-internal := tst-mallocstate tst-scratch_buffer

> posix/tst-glob_lstat_compat.c:compat_symbol_reference (libc, glob,
> glob, GLIBC_2_1);
> posix/tst-glob_lstat_compat.c:compat_symbol_reference (libc, glob,
> glob, GLIBC_2_0);
> posix/tst-spawn4-compat.c:compat_symbol_reference (libc, posix_spawn,
> posix_spawn, GLIBC_2_2);
> posix/tst-spawn4-compat.c:compat_symbol_reference (libc, posix_spawnp,
> posix_spawnp, GLIBC_2_2);

tests-internal	:= bug-regex5 bug-regex20 bug-regex33 \
		   tst-rfc3484 tst-rfc3484-2 tst-rfc3484-3 \
		   tst-glob_lstat_compat tst-spawn4-compat

And so on.

tests-internal changes -DMODULE_NAME=.  I can't easily do that for
nptl/tst-cleanup4aux.c.

Maybe we could move some of these other tests from tests-internal to
tests because they do not test internals anymore.

Thanks,
Florian