[Bug sanitizer/88479] sanitizer should provide an option to detect conversion to signed integer that overflows

[vincent-gcc at vinc17 dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88479

--- Comment #5 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> ---
(In reply to jos...@codesourcery.com from comment #4)
> If you want to do modulo arithmetic on signed values, the idiom (in 
> common-usage C which supports conversions to signed integer types as being 
> modulo) is to convert to unsigned, do arithmetic on unsigned and convert 
> back to signed.

The conversion back to signed can be done without involving the
implementation-defined behavior, e.g. with a macro that consider the two cases.
This is much better as the conversion is explicit.