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From: Thomas Koenig <tkoenig@netcologne.de>
To: Michael Meissner <meissner@linux.ibm.com>,
	Jakub Jelinek <jakub@redhat.com>,
	fortran@gcc.gnu.org, gcc@gcc.gnu.org,
	Tobias Burnus <tobias@codesourcery.com>,
	Segher Boessenkool <segher@kernel.crashing.org>,
	David Edelsohn <dje.gcc@gmail.com>
Subject: Re: libgfortran.so SONAME and powerpc64le-linux ABI changes
Date: Thu, 7 Oct 2021 08:08:21 +0200	[thread overview]
Message-ID: <3dacfdf6-6b23-f307-969a-94265b506edb@netcologne.de> (raw)
In-Reply-To: <YV5rGhDBjX3IxMlX@toto.the-meissners.org>

On 07.10.21 05:35, Michael Meissner via Fortran wrote:
> I tried this at one point.  There are a lot of hidden assumptions that the kind
> number is the number of bytes.  I'm sure it can be tracked down, but the
> problem is with these assumptions is you can't prove a negative (i.e. you never
> know that you've missed some).

So, summing up from the Fortran side, I'd say the best course of action
is to

- make KIND=16 into IEEE QP

- bump the SONAME on on affected systems on POWER and nowhere else

- have a preprocessor flag so we can #ifdef out code which is relevant
   only there

- provide a CONVERT option (have to think of a suitable syntax) to
   do unformatted I/O either in IEEE QP or double double, but only
   on affected systems, so people can set this either via a CONVERT
   option on open or an environment variable.  For OPEN, we should
   extend the existing one, for an environment variable, I'd say
   we should use a new one and reuse the existing parsing routines.

Sounds like a reasonable minimum of user pain to me.

The rest I'll leave to the experts in all things ABI and POWER :-)

  reply	other threads:[~2021-10-07  6:08 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-04 10:07 Jakub Jelinek
2021-10-04 11:24 ` Richard Biener
2021-10-04 11:36   ` Jakub Jelinek
2021-10-04 12:31     ` Jakub Jelinek
2021-10-04 14:14 ` Jakub Jelinek
2021-10-04 16:47   ` Joseph Myers
2021-10-04 18:33   ` Segher Boessenkool
2021-10-04 19:24     ` Joseph Myers
2021-10-05 17:43       ` Segher Boessenkool
2021-10-14 19:39         ` Bill Schmidt
2021-10-15  0:26           ` Segher Boessenkool
2021-10-05 20:16   ` Thomas Koenig
2021-10-05 21:54     ` Segher Boessenkool
2021-10-06  6:59       ` Thomas Koenig
2021-10-06 15:17         ` Segher Boessenkool
2021-10-06 15:41           ` Jakub Jelinek
2021-10-06 16:07             ` Segher Boessenkool
2021-10-06 16:34               ` Jakub Jelinek
2021-10-06 16:59                 ` Segher Boessenkool
2021-10-06 17:07                   ` Jakub Jelinek
2021-10-06 17:50                     ` Segher Boessenkool
2021-10-06 19:30                       ` Peter Bergner
2021-10-06 17:13                 ` Joseph Myers
2021-10-06 18:39                   ` Segher Boessenkool
2021-10-06 19:42                     ` Joseph Myers
2021-10-06 20:57                       ` Segher Boessenkool
2021-10-06 21:55                         ` Joseph Myers
2021-10-06 22:03                         ` Joseph Myers
2021-10-08 17:53                           ` Segher Boessenkool
2021-10-11 20:11                             ` Joseph Myers
2021-10-15  0:16                               ` Segher Boessenkool
2021-10-06 15:42           ` David Edelsohn
2021-10-06 16:19             ` Segher Boessenkool
2021-10-06 17:38               ` David Edelsohn
2021-10-07  3:42           ` Michael Meissner
2021-10-08 21:10             ` Segher Boessenkool
2021-10-07  9:48         ` Alastair McKinstry
2021-10-07  9:56           ` Andreas Schwab
2021-10-07 10:01             ` Jakub Jelinek
2021-10-07 12:43               ` Alastair McKinstry
2021-10-05 21:53   ` Jonathan Wakely
2021-10-07  3:35 ` Michael Meissner
2021-10-07  6:08   ` Thomas Koenig [this message]
2021-10-07  9:40     ` Jakub Jelinek
2021-10-07 15:24     ` Michael Meissner
2021-10-07 15:33       ` Jakub Jelinek
2021-10-08  6:35         ` Thomas Koenig
2021-10-08  7:20           ` Iain Sandoe
2021-10-08 16:26             ` Thomas Koenig
2021-10-08 19:11               ` Iain Sandoe
2021-10-08 22:55                 ` Thomas Koenig
2021-10-08 23:18                   ` Iain Sandoe
2021-10-09  9:11                     ` Thomas Koenig
2021-10-09  9:19                       ` Iain Sandoe
2021-10-09  9:25                       ` Jakub Jelinek
2021-10-09  7:44                   ` Andreas Schwab
2021-10-10 16:14                     ` Florian Weimer
2021-10-15 13:50 ` Bill Schmidt
2021-10-15 14:20   ` Jakub Jelinek
2021-10-15 18:05     ` Thomas Koenig
2021-10-15 18:11       ` Jakub Jelinek
2021-10-15 18:58         ` Thomas Koenig
2021-10-15 22:24     ` Segher Boessenkool
2021-10-15 22:36   ` Segher Boessenkool
2021-10-18 19:02   ` Joseph Myers
2021-10-28  3:10 ` Michael Meissner
2021-10-29  3:36 ` libgfortran.so SONAME and powerpc64le-linux ABI changes (work in progress patches) Michael Meissner
2021-10-29 19:07   ` Thomas Koenig
2021-10-29 21:06     ` Michael Meissner
2021-11-01 15:56       ` Bill Schmidt
2021-11-02 15:40         ` Michael Meissner
2021-10-30  0:16 ` libgfortran.so SONAME and powerpc64le-linux ABI changes (2nd patch) Michael Meissner
2021-10-30  9:30   ` Thomas Koenig
2021-10-30 10:03     ` Jakub Jelinek
2021-10-30 10:31       ` Thomas Koenig

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