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From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/42958] Weird temporary array allocation
Date: Fri, 05 Feb 2010 09:32:00 -0000 [thread overview]
Message-ID: <20100205093232.1052.qmail@sourceware.org> (raw)
In-Reply-To: <bug-42958-10053@http.gcc.gnu.org/bugzilla/>
------- Comment #3 from rguenther at suse dot de 2010-02-05 09:32 -------
Subject: Re: Weird temporary array allocation
On Fri, 5 Feb 2010, pault at gcc dot gnu dot org wrote:
> ------- Comment #2 from pault at gcc dot gnu dot org 2010-02-05 05:36 -------
> (In reply to comment #1)
>
> > Why there is a negative check? Well, I do not know. I also can speculate about
> > a poor man's overflow check, which sometimes indeed works, but often fails.
>
> I suspect that you are being generous and that this is rather a sin of omission
> rather than commission.
>
>
> > Paul, what do you think?
>
> I think that your arguments are correct.
>
> >
> > (PS: POSIX Allows "ptr = malloc(0); free(ptr)", where "malloc(0)" returns
> > either NULL or a unique pointer.)
>
> Indeed.
Btw, should there be the same error reporting or if (allocated) behavior
on Frontend-generated temporaries? I see this from the temporaries
generated by the scalarizer and the introduced control-flow makes it
very hard to remove unnecessary temporaries in the middle-end later.
Thx,
Richard.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42958
next prev parent reply other threads:[~2010-02-05 9:32 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-04 16:56 [Bug fortran/42958] New: " rguenth at gcc dot gnu dot org
2010-02-04 19:33 ` [Bug fortran/42958] " burnus at gcc dot gnu dot org
2010-02-05 5:36 ` pault at gcc dot gnu dot org
2010-02-05 9:32 ` rguenther at suse dot de [this message]
2010-02-05 14:24 ` rguenth at gcc dot gnu dot org
2010-02-17 20:17 ` jvdelisle at gcc dot gnu dot org
2010-02-20 8:31 ` burnus at gcc dot gnu dot org
2010-03-27 18:55 ` pault at gcc dot gnu dot org
2010-03-27 19:06 ` rguenth at gcc dot gnu dot org
2010-03-27 19:06 ` rguenth at gcc dot gnu dot org
2010-03-27 19:08 ` rguenth at gcc dot gnu dot org
2010-03-27 19:12 ` rguenth at gcc dot gnu dot org
2010-03-28 12:57 ` burnus at gcc dot gnu dot org
2010-03-28 13:05 ` burnus at gcc dot gnu dot org
2010-03-28 13:57 ` burnus at gcc dot gnu dot org
2010-03-28 14:11 ` burnus at gcc dot gnu dot org
2010-03-28 14:45 ` rguenther at suse dot de
2010-04-16 8:18 ` burnus at gcc dot gnu dot org
2010-04-28 14:52 ` rguenth at gcc dot gnu dot org
2010-04-28 15:16 ` amonakov at gcc dot gnu dot org
2010-04-28 15:20 ` jv244 at cam dot ac dot uk
2010-04-28 15:43 ` jb at gcc dot gnu dot org
2010-04-29 10:02 ` paul dot richard dot thomas at gmail dot com
2010-04-29 13:19 ` jakub at gcc dot gnu dot org
2010-04-29 19:09 ` tkoenig at gcc dot gnu dot org
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