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From: "jason at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/53220] [4.7/4.8 Regression] g++ mis-compiles compound literals
Date: Mon, 07 May 2012 14:33:00 -0000	[thread overview]
Message-ID: <bug-53220-4-rQQMiLSfvi@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-53220-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53220

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|jason at redhat dot com     |jason at gcc dot gnu.org
   Target Milestone|4.7.1                       |4.8.0

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2012-05-07 14:29:52 UTC ---
Compound literals are not part of C++, so correctness is a matter of debate. 
In C, a compound literal designates an object with automatic storage duration. 
In G++, a compound literal designates a temporary object, just like a normal
cast or function-like cast.

This is a significant difference in semantics, which leads to the problem
encountered here; the temporary object goes out of scope immediately after the
initialization of p, so the loop has undefined behavior.

It would be possible for G++ to model the C semantics more closely.


  parent reply	other threads:[~2012-05-07 14:31 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-03 19:50 [Bug c++/53220] New: " ppluzhnikov at google dot com
2012-05-03 19:53 ` [Bug c++/53220] " ppluzhnikov at google dot com
2012-05-03 22:38 ` [Bug c++/53220] [4.7/4.8 Regression] " hjl.tools at gmail dot com
2012-05-04  9:03 ` rguenth at gcc dot gnu.org
2012-05-04 18:53 ` xinliangli at gmail dot com
2012-05-07 14:33 ` jason at gcc dot gnu.org [this message]
2012-05-07 16:25 ` xinliangli at gmail dot com
2012-05-07 16:55 ` ppluzhnikov at google dot com
2012-05-07 17:18 ` xinliangli at gmail dot com
2012-05-07 17:55 ` jason at gcc dot gnu.org
2012-05-08  0:34 ` xinliangli at gmail dot com
2012-05-08  2:22 ` jason at gcc dot gnu.org
2012-05-17  0:13 ` ppluzhnikov at google dot com
2012-05-22 17:42 ` jason at gcc dot gnu.org
2012-05-22 17:50 ` ppluzhnikov at google dot com
2012-05-22 18:05 ` ppluzhnikov at google dot com
2012-05-26 21:20 ` jason at gcc dot gnu.org
2012-05-30 14:52 ` jason at gcc dot gnu.org
2012-06-03  4:50 ` jason at gcc dot gnu.org
2012-06-20  1:59 ` ppluzhnikov at google dot com
2012-06-20  7:20 ` jason at gcc dot gnu.org
2013-05-01  9:54 ` superaxioma at hotmail dot com
2013-05-01 19:13 ` jason at gcc dot gnu.org
2023-11-28 21:29 ` cvs-commit at gcc dot gnu.org

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