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Date: Wed, 22 Sep 2004 05:33:00 -0000
From: Mathieu Malaterre <mmalater@nycap.rr.com>
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Subject: Warning flags for unsigned operations (unsafe)
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Hello,

	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 ?

Thanks,
Mathieu