[PATCH v3] Change default to -fno-math-errno
Joseph Myers
joseph@codesourcery.com
Thu Oct 4 12:27:00 GMT 2018
On Thu, 4 Oct 2018, Richard Biener wrote:
> The other issue is that we're treating -fno-math-errno as disabling
> errno handling in general (not only for math functions). That would
Also, is it treated as meaning the math functions *do not set errno* (so a
load of errno (or of anything that might be errno) before a math function
call could be moved after the call)? Because the proper meaning is simply
*may not set errno* (so you shouldn't be able to move an errno load across
a call like that, since the call might still happen to clobber it - of
course if it happens to be a call that GCC inlines and eliminates any
possibility of errno setting that way, e.g. sqrt on many platforms, or a
platform where libm never sets errno at all, then such a move is safe).
--
Joseph S. Myers
joseph@codesourcery.com
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