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From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/41874] Incorrect "dereferencing type-punned pointer will break strict-aliasing rules" warning
Date: Fri, 06 Nov 2009 09:16:00 -0000 [thread overview]
Message-ID: <20091106091601.29556.qmail@sourceware.org> (raw)
In-Reply-To: <bug-41874-13604@http.gcc.gnu.org/bugzilla/>
------- Comment #2 from rguenther at suse dot de 2009-11-06 09:16 -------
Subject: Re: Incorrect "dereferencing type-punned pointer
will break strict-aliasing rules" warning
On Fri, 6 Nov 2009, pinskia at gcc dot gnu dot org wrote:
> ------- Comment #1 from pinskia at gcc dot gnu dot org 2009-11-06 09:09 -------
> 4.5 also fails and I cannot figure why if I do:
"fails"?
> #include <new>
> struct APInt {
> int i;
> };
> int main() {
> APInt I;
> void *d;
> char Data[sizeof(APInt)];
> new((void*)Data)APInt();
> d = Data;
> *(APInt*)d = I;
> }
>
> GCC does not warn.
Of course not - the code is perfectly valid (apart from Data
not having suitable alignment for APInt, but that's unrelated
to aliasing issues).
Richard.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41874
next prev parent reply other threads:[~2009-11-06 9:16 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-30 1:32 [Bug c++/41874] New: " jyasskin at gmail dot com
2009-11-06 9:09 ` [Bug c++/41874] " pinskia at gcc dot gnu dot org
2009-11-06 9:16 ` rguenther at suse dot de [this message]
2009-11-06 9:19 ` pinskia at gcc dot gnu dot org
2009-11-06 9:20 ` rguenth at gcc dot gnu dot org
2010-01-31 9:38 ` fw at deneb dot enyo dot de
2010-01-31 11:18 ` rguenth at gcc dot gnu dot org
[not found] <bug-41874-4@http.gcc.gnu.org/bugzilla/>
2010-10-05 0:11 ` muravev at yandex dot ru
2010-10-05 4:49 ` fw at gcc dot gnu.org
2010-10-06 19:44 ` muravev at yandex dot ru
2010-10-06 20:57 ` rguenther at suse dot de
2012-10-15 9:27 ` paolo.carlini at oracle dot com
2012-10-15 9:45 ` rguenth at gcc dot gnu.org
2022-01-08 10:49 ` pinskia at gcc dot gnu.org
2022-12-03 22:03 ` jason at gcc dot gnu.org
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