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From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: wempwer@gmail.com
Cc: gcc-help <gcc-help@gcc.gnu.org>
Subject: Re: how to make gcc warn about arithmetic signed overflow
Date: Sat, 21 Sep 2013 17:24:00 -0000	[thread overview]
Message-ID: <CAH6eHdTToM+TMy55m5HYo39DC8nA0RrTma1Bp5OnhUtPErMfOA@mail.gmail.com> (raw)
In-Reply-To: <20130921164609.GC3086@a.lan>

On 21 September 2013 17:46,  wrote:
> Is it possible for gcc to produce a
> warning in such situation?

If ab and bc are 'const' then G++ will warn:

o.cc: In function ‘int main()’:
o.cc:5:14: warning: integer overflow in expression [-Woverflow]
 int r = ab * bc;
              ^

The C compiler still doesn't warn though, due to different rules for
how constants are handled between C and C++.

  reply	other threads:[~2013-09-21 17:24 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-21 16:45 wempwer
2013-09-21 17:24 ` Jonathan Wakely [this message]
2013-09-21 17:41   ` wempwer
2013-09-21 18:30     ` Jonathan Wakely
2013-09-21 18:50       ` wempwer
2013-09-21 19:55         ` Jędrzej Dudkiewicz
2013-09-21 20:16           ` wempwer
2013-09-21 20:52             ` Jędrzej Dudkiewicz
2013-09-21 21:07               ` wempwer
2013-09-23  4:04       ` James K. Lowden
2013-09-23  7:55         ` Jonathan Wakely
2013-09-23 15:47           ` James K. Lowden
2013-09-23 21:50             ` Jonathan Wakely
2013-09-23 22:44               ` James K. Lowden
2013-09-23 23:20                 ` Jonathan Wakely
2013-09-23 19:38         ` Dave Allured - NOAA Affiliate
2013-09-23 19:43           ` Oleg Endo
2013-09-23 20:37             ` Dave Allured - NOAA Affiliate
2013-09-23 19:48           ` Andrew Haley
2013-09-23 22:00             ` James K. Lowden
2013-09-24 17:48               ` Andrew Haley
2013-09-26  2:30                 ` James K. Lowden
2013-09-26  8:29                   ` Vincent Lefevre
2013-09-26 14:49                     ` Andrew Haley
2013-09-26 17:03                       ` Vincent Lefevre
2013-09-26 18:19                         ` Andrew Haley
2013-09-27  7:58                           ` Vincent Lefevre
2013-09-27  8:23                             ` Andrew Haley
2013-09-27  9:28                               ` Vincent Lefevre
2013-09-27  9:43                                 ` Andrew Haley
2013-09-26 17:41                   ` Andrew Haley
2013-09-24  7:42           ` Brian Drummond
2013-09-21 17:53   ` Marc Glisse
2013-09-21 18:09     ` wempwer
2013-09-21 18:27       ` Jonathan Wakely
2013-09-21 19:32         ` wempwer
2013-09-22 15:52           ` Jonathan Wakely
2013-09-23 13:04           ` David Brown
2013-09-21 17:36 ` Brian Drummond
2013-09-21 17:45   ` wempwer

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