[Bug middle-end/93806] Wrong optimization: instability of floating-point results with -funsafe-math-optimizations leads to nonsense

[vincent-gcc at vinc17 dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93806

--- Comment #30 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> ---
(In reply to Vincent Lefèvre from comment #28)
> A slightly modified version of the example, showing the issue with GCC 5 to
> 7 (as the noipa attribute directive has been added in GCC 8):

Correction: This allows to test with old GCC versions, and this shows that the
bug has been introduced in GCC 6. GCC 5 outputs consistent values.