On 2/21/07, Mark Mitchell <mark@codesourcery.com> wrote:
To be honest, my instinct for the FSF is to take the 4% hit and get rid
of this nasty class of bugs. Users measure compiler quality by more
than just floating-point benchmarks; FP code is a relatively small
(albeit important, and substantial) set of all code. That's why I asked
Danny for the patches in the first place.
Of course the speed of a compiler is measured on testcases where
speed matters - and this is usually FP code. Now based on this reasoning
we could (as CodeSourcery probably did) enable -fno-strict-aliasing by
default, which fixes the class of 4.1.x bugs we are talking about. With
leaving the possibility for the user to specify -fstrict-aliasing and get
back the speed for FP code with the risk of getting wrong-code.
Now, the realistic choices for 4.2.0 as I see them are, in order of my
personal preference:
1) Ship 4.2.0 as is
2) Ship 4.2.0 with the aliasing fixes reverted
3) no more reasonable option. Maybe don't ship 4.2.0 at all.