https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78509
--- Comment #8 from James Greenhalgh <jgreenhalgh at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #7)
> (In reply to James Greenhalgh from comment #6)
> > None of the logic was there in the original code, so there is not much to
> > compare.
>
> ?? Since -fexcess-precision=standard has been introduced, gcc has the
> excess precision notion. So there is something to compare.
> E.g. try
> float foo (float x, float y, float z)
> {
> return x + y + z;
> }
> before your changes with
> -fdump-tree-gimple -m32 -msse2 -mno-80387 -fexcess-precision=standard
> -fdump-tree-gimple -m32 -msse2 -mfpmath=387+sse -fexcess-precision=standard
> -fdump-tree-gimple -m32 -msse2 -mfpmath=387 -fexcess-precision=standard
> -fdump-tree-gimple -m32 -msse2 -mfpmath=sse -fexcess-precision=standard
> -fdump-tree-gimple -m32 -msse -mno-sse2 -mfpmath=sse
> -fexcess-precision=standard
> to match the different cases in your hook, and compare that to what you get
> with the current trunk.
Right, I think we might have been talking about comparing different things.
That works for a test of observable behaviour.
I've done what I suggested above, tested it as you suggested, and posted a fix
to the mailing list https://gcc.gnu.org/ml/gcc-patches/2016-11/msg02568.html
