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

[Richard Kenner]

> Are you volunteering to audit the present cases and argue whether they
> fall in the "traditional" cases?

I'm certainly willing to *help*, but I'm sure there will be some cases
that will require discussion to get a consensus.

> Note that -fwrapv also _enables_ some transformations on signed
> integers that are disabled otherwise.  We for example constant fold
> -CST for -fwrapv while we do not if signed overflow is undefined.
> Would you change those?

I don't understand the rationale for not wrapping constant folding when
signed overflow is undefined: what's the harm in "defining" it as wrapping
for that purpose?  If it's undefined, then why does it matter what we
fold it to?  So we might as well fold it to what traditional code expects.