Re: checking against signed integer overflow

[Paul Eggert]

On 12/5/20 1:42 PM, Bruno Haible wrote:
> How about adding a macro
>
>    #define SAFE_INT_MULTIPLY(a, b, result) \
>      ! INT_MULTIPLY_WRAPV (a, b, result)
>
> and documenting it as a safe way to do integer multiplication, regardless of
> compiler options in effect?

Sure, we can do that. I prefer the name INT_MULTIPLY_OK though, as it's shorter, 
it fits better with intprops.h's naming conventions, and "SAFE" is a little 
misleading (the macro is not safe when, for example, its last argument is a null 
pointer). I installed the attached patch to do that; if you're not a fan we can 
always revert it.

Your reaction to the *_WRAPV names just goes to show how bad I am with 
marketing....

0001-intprops-Add-INT_ADD_OK-etc.patch
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