how to make gcc warn about arithmetic signed overflow

[Vincent Lefevre]

On 2013-09-26 15:49:05 +0100, Andrew Haley wrote:
> On 09/26/2013 09:29 AM, Vincent Lefevre wrote:
> > On 2013-09-25 22:29:58 -0400, James K. Lowden wrote:
> >> You mean that a naïve rendering of the source code implies an overflow
> >> where none might exist in the actual emitted object code.  And,
> >> presumably, the converse: that even if the source is written such that
> >> there logically can't be an overflow, the compiler might render object
> >> code that does.
> > 
> > The converse is forbidden.
> 
> You'll find it hard to justify that by any language in the standard.

What do you mean?

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