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Re: Processor-specific code

"Joseph S. Myers" <joseph@codesourcery.com> writes:

> On Thu, 14 Apr 2005, Richard Henderson wrote:
> 
> > On Thu, Apr 14, 2005 at 10:47:26AM -0700, Steve Kargl wrote:
> > > Does gcc support 
> > > #pragma STDC FENV_ACCESS
> > 
> > No, but we currently act like access is "on".
> 
> I thought we acted like it is "off", allowing CSE and constant folding 
> which might be affected by changes in rounding mode.  Certainly some of 
> Stephen Moshier's testcases (attached to bug 20785) fail.

The flag that controls this is -ftrapping-math, and it defaults to "on".

That said, though, there *are* bugs.  For instance, we currently take
code like:

(void) 0. / 1.;

and delete it as dead, even though it has side-effects.
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