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From: "hjl dot tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/35200] [4.3 Regression] bogus aliasing warning
Date: Thu, 14 Feb 2008 20:55:00 -0000 [thread overview]
Message-ID: <20080214205418.5259.qmail@sourceware.org> (raw)
In-Reply-To: <bug-35200-682@http.gcc.gnu.org/bugzilla/>
------- Comment #6 from hjl dot tools at gmail dot com 2008-02-14 20:54 -------
(In reply to comment #5)
> Can you when you debug the function, please dump the VOPs also since then it
> should become obvious the issue.
>
> Anyways I don't think this an bogus warning and really I think this is a code
> issue.
>
> This is actually documented this way in fact unions cannot be used this way.
>
> That is you cannot do:
>
> float f(int a)
> {
> union {
> int i[1];
> float f[1];
> } g;
>
> int *d = g.i;
> float *f = g.f;
> *d = a;
> return *f;
> }
>
> -- Pinski
>
Where is this documented in ISO C?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35200
next prev parent reply other threads:[~2008-02-14 20:55 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-02-14 19:50 [Bug tree-optimization/35200] New: [4.3 Regression] gcc 4.3 failed to compile binutils hjl dot tools at gmail dot com
2008-02-14 19:52 ` [Bug tree-optimization/35200] " hjl dot tools at gmail dot com
2008-02-14 19:58 ` pinskia at gcc dot gnu dot org
2008-02-14 20:01 ` [Bug tree-optimization/35200] [4.3 Regression] bogus aliasing warning pinskia at gcc dot gnu dot org
2008-02-14 20:17 ` hjl dot tools at gmail dot com
2008-02-14 20:22 ` pinskia at gcc dot gnu dot org
2008-02-14 20:55 ` hjl dot tools at gmail dot com [this message]
2008-02-14 22:09 ` Andrew Pinski
2008-02-14 21:20 ` rguenth at gcc dot gnu dot org
2008-02-14 21:24 ` rguenth at gcc dot gnu dot org
2008-02-14 22:10 ` pinskia at gmail dot com
2008-02-14 22:57 ` hjl dot tools at gmail dot com
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