Re: Async I/O patch with compilation fix

[David Edelsohn <dje dot gcc at gmail dot com>]

Thomas,

Once the plural.c file has been re-generated incorrectly using the local
Yacc, it must be deleted and checked out again.  Did you pull it fresh from
the repository in your AIX tree after the incorrect checkout?

Thanks, David


On Wed, Aug 22, 2018 at 5:30 PM Thomas Koenig <tkoenig@netcologne.de> wrote:

> Hi David,
>
> > This patch broke bootstrap on AIX again.  This is completely
> unacceptable.
>
> Again, sorry for the breakage.
>
> I faced quite some challenges trying to get bootstrap to
> work on gcc119. Despite quite a few e-mails (plus hints in a PR)
> that I received, none of the hints for bootstrap I got actually got
> it to work. I finally gave up after four or five different failures,
> and the patch was committed because every test
> that _could_ be run did show no failure.
>
> Had we received instructions that work for bootstrapping on AIX,
> we would have tested the patch there.
>
> If it were possible to add instructions that do work for AIX
> bootstrapping to the compile farm wiki, that would be great.
>
> If you (or somebody else who has the requisite AIX fu) could test
> patches that are known to be difficult, that would also be
> great.
>
> As long as we have no other solution, it is probably best to #ifdef out
> AIX any additional pthread-related functionality for libgfortran that
> might be coming along. That can always be integrated later, if somebody
> can re-implement POSIX condition variables for libgfortran from what
> AIX provides.
>
> Let's talk about how to proceed at the GNU cauldron, over a beer.
> Both Nicolas and I will be there.
>
> In the meantime, I have committed the following patch (r263788) as
> obvious after regression-testing on Linux both with ASYNC_IO set
> to 1 and to 0.  Let me know how that works out.
>
> 2018-08-22  Thomas Koenig  <tkoenig@gcc.gnu.org>
>
>         * async.h: Set ASYNC_IO to zero if _AIX is defined.
>         (struct adv_cond): If ASYNC_IO is zero, the struct has no members.
>         (async_unit): If ASYNC_IO is zero, remove unneeded members.
>
> 2018-08-22  Thomas Koenig  <tkoenig@gcc.gnu.org>
>
>         * gfortran.texi: Mention that asynchronous I/O does
>         not work on systems which lack condition variables, such
>         as AIX.
>
> Regards
>
>         Thomas
>