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From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: Christoph Groth <cwg@falma.de>
Cc: gcc-help@gcc.gnu.org
Subject: Re: (undocumented?) difference between gcc 4.6 and 4.7 (C++ implicit template instantiation)
Date: Tue, 28 Aug 2012 17:29:00 -0000	[thread overview]
Message-ID: <CAH6eHdRVqDovxQtddZxKTbj2Pivts1YtY+NVOJYk=upe1yh6QA@mail.gmail.com> (raw)
In-Reply-To: <87vcg3c9rz.fsf@falma.de>

On 28 August 2012 16:32, Christoph Groth wrote:
> Dear GCC experts,
>
> I've been unable to find a description of this issue in any changelog.
> Actually, I wonder whether the behavior of 4.6 or that of 4.7 is the
> correct one with regard to the C++ language standard.
>
> Is this a known issue which has been fixed in 4.7, or rather a
> regression from 4.6?

The change in behaviour might be due to the patch for
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48883

But I think the program has undefined behaviour according to
[expr.reinterpret.cast]/6, because it calls a function through a
pointer to a different function type.  Specifically, something<long>
which has type void*(Class<long>*) is called through a pointer of type
void*(*)(void*).

  reply	other threads:[~2012-08-28 16:45 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-28 17:24 Christoph Groth
2012-08-28 17:29 ` Jonathan Wakely [this message]
2012-08-28 20:32   ` Christoph Groth

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