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

From: Robert Dewar
Subject: Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."
Date: Sat, 30 Dec 2006 06:48:31 -0500
User-agent: Thunderbird (Windows/20061207)

Paul Eggert wrote:
Nor would I relish the prospect of keeping wrapv assumptions out of
GCC as other developers make further contributions, as the wrapv
assumption is so natural and pervasive.
It's neither natural not pervasive to me!  I would never write code
that way

That's great, but GCC has had many other hands stirring the pot.
I daresay a careful scan would come up with many other examples of
undefined behavior due to signed integer overflow.  (No doubt
you'll be appalled by them as well, but there they are.)

Not so appalling really, given that relying on wrapping is as
has been pointed out in this thread, the most natural and
convenient way of testing for overflow. It is really *quite*
difficult to test for overflow while avoiding overflow, and
this is something that is probably not in the lexicon of
many C programmers.

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