On Thu, 26 May 2005, Vincent Lefevre wrote:
On 2005-05-25 19:27:21 +0200, Allan Sandfeld Jensen wrote:
Yes. I still don't understand why gcc doesn't do -ffast-math by
default like all other compilers.
No! And I really don't think that other compilers do that.
Have you looked, or are you just guessing?
I know for a fact that XLC does it at -O3+, and unless i'm
misremembering, icc does it at -O2+.
Both require flags to turn the behavior *off* at those opt levels.
XLC will give you a warning when it sees itself making an optimization
that may affect precision, saying that if you don't want this to happen,
to use a flag.