[issue30104] Float rounding errors on AMD64 FreeBSD CURRENT Debug 3.x buildbot

[STINNER Victor]

STINNER Victor added the comment:

test_strtod fails on FreeBSD using clang 4.0, but pass using clang 3.8.

Links:

* https://gcc.gnu.org/wiki/FloatingPointMath
* https://gcc.gnu.org/wiki/Math_Optimization_Flags
* ICC fp-model: https://software.intel.com/en-us/node/682946

GCC options:

* -ffp-contract=off / -ffp-contract=fast
* -fp-model (not supported by clang)
* -mfpmath=sse: no effect on Clang, it's already the default and -mfpmath=387 is not supported on x86_64 ISA
* -ffast-math
* -fexcess-precision=standard: not supported by clang

----------

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue30104>
_______________________________________