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Re: GCC beaten by ICC in stupid trig test!
Joe Buck wrote:
I'm aware of the usual examples. Do you think that we need yet another
fast-math flag to allow the compiler to reassociate values in
floating-point arithmetic? -freally-unsafe-math-optimizations perhaps?
Or maybe such a programmer as you describe will just turn off
-funsafe-math-optimizations.
No. Why would we need such a thing? If the user does not care about
order of evaluation, the user can write a+b+c .
That's an appropriate statement for Fortran, but not for other languages
like C, C++ and Ada, where a+b+c is semantically equivalent to (a+b)+c
and the reassociation is not allowed in either case.
I dislike anything being called an optimization, unsafe or not, when it
is not an optimization but in fact a distortion of required language
semantics.