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Re: What is acceptable for -ffast-math? (Was: associative law in combine)
- To: dewar at gnat dot com, torvalds at transmeta dot com
- Subject: Re: What is acceptable for -ffast-math? (Was: associative law in combine)
- From: dewar at gnat dot com
- Date: Mon, 30 Jul 2001 09:00:02 -0400 (EDT)
- Cc: gcc at gcc dot gnu dot org, moshier at moshier dot ne dot mediaone dot net,tprince at computer dot org
<<It's sad that C99 doesn't seem to allow the Fortran kind of "you go and
make the best you can of this expression unless I tell you otherwise".
>>
But if you look at real Fortran codes, they are full of parentheses to stop
the compiler from messing around, and in fact most Fortran compilers do only
very limited mucking even when no parens are present. I would be shocked
to find a FOrtraqn compiler that changed
a*c + b*c
into
(a+b)*c
a totally diffrerent expression!
I would have written the second expression if I had wanted that effect.