Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."

[Robert Dewar <dewar at adacore dot com>]

Gabriel Dos Reis wrote:

> I have been looking into infer_loop_bounds_from_signedness() called
> from infer_loop_bounds_from_undefined().
> At some places, nowrap_type_p() is used but this function operates
> only on types, so there will be too many false positive there; yet we
> will miss warning through that case.

My inclination is to skip the warning for the loop
induction variable case. I think this will generate
lots of false positives, and almost no useful
warnings (I still think this is the one and only
case where the undefined optimization should be done,
in fact I think it would be useful to have a switch
that says

-fwrapv-in-all-cases-except-loop-bounds