On Mon, 27 Jan 2020, Ulrich Weigand wrote: > I see. I guess that makes me wonder what -fno-fast-math *ever* does > (except canceling a -ffast-math earlier on the command line). Looking > at the current code, -fno-fast-math (just like -ffast-math) only ever > sets flags whose default is not overridden on the command line, but > then it always sets them to their default value!
As a general principle, more specific flags take precedence over less specific ones, regardless of the command-line order. So it's correct for -ffast-math and -fno-fast-math not to do anything with a flag that was explicitly overridden by the user (modulo any issues where a particular combination of flags is unsupported by GCC, as with the "%<-fassociative-math%> disabled; other options take precedence" case in toplev.c). -- Joseph S. Myers jos...@codesourcery.com
