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Re: Setting -frounding-math by default
On Sun, 8 Mar 2009, Richard Guenther wrote:
> We try to have a sensible default setting that doesn't prevent constant
> folding (which -frounding-math does).
-ftrapping-math implemented according to its specification would prevent a
lot of constant folding (at least, the "inexact" and other exceptions from
constant expressions not in static initializers should be preserved,
although you could fold a complicated expression down to a simpler one
that still gives the right set of exceptions). I suspect we might
therefore end up wanting a weaker version of -ftrapping-math as the
default with the full present specification of -ftrapping-math not being
the default if it gets implemented.
--
Joseph S. Myers
joseph@codesourcery.com