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

[Robert Dewar]

Richard Kenner wrote:
> > The burden of proof ought to be on the guys proposing -O2
> > optimizations that break longstanding code, not on the skeptics.
>
> There's also a burden of proof that proposed optimizations will actually
> "break longstanding code".  So far, all of the examples of code shown
> that assumes wrapv semantics are such that it's nearly impossible to see
> any useful optimization that would break it!

Also, there are bug reports filed, so we certainly DO have examples
of code breaking, and quite a few reports have discussed the need
to enable -fwrapv for specific code bases.