From: Mathieu Malaterre <mmalater@nycap.rr.com>
To: Giovanni Bajo <giovannibajo@libero.it>
Cc: gcc@gcc.gnu.org
Subject: Re: Warning flags for unsigned operations (unsafe)
Date: Fri, 24 Sep 2004 06:31:00 -0000 [thread overview]
Message-ID: <41539FCC.3050503@nycap.rr.com> (raw)
In-Reply-To: <018901c4a1e6$d6a3b720$dc4e2a97@bagio>
Giovanni Bajo wrote:
> Mathieu Malaterre wrote:
>
>
>>I have been googling around and I couldn't find out if gcc had a
>>warning flag for unsigned operation. For example, even the linear
>>interpolation on [a,b] can be tricky to code:
>>
>>1.
>>c = a + t * (b - a); //unsafe
>>
>>2.
>>c = (1.0 - t) * a + t * b; //safe
>>
>>Number 1 will fail when both a and b are unsigned and let say b - a =
>>-1 (math speaking). Is there something in gcc that could warn me for
>>this kind of operation ?
>
>
> Would you please file a bug report in Bugzilla and later mark it as a
> enhancement request?
Done:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17645
If I did something wrong just let me know, I'll correct it,
Mathieu
next prev parent reply other threads:[~2004-09-24 4:17 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-09-22 5:33 Mathieu Malaterre
2004-09-22 10:00 ` sizeof(union) and #pragma pack() Dave Trollope, Diane Barrowman
2004-09-22 20:41 ` Geoffrey Keating
2004-09-22 14:57 ` Warning flags for unsigned operations (unsafe) Dave Korn
2004-09-22 15:12 ` Robert Dewar
2004-09-22 20:50 ` Luca Masini
2004-09-23 1:37 ` Mathieu Malaterre
2004-09-24 6:20 ` Giovanni Bajo
2004-09-24 6:31 ` Mathieu Malaterre [this message]
2004-09-22 15:38 Thomas R. Truscott
2004-09-22 16:18 ` Robert Dewar
2004-09-22 16:31 ` Robert Dewar
2004-09-22 16:53 ` Dave Korn
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