Eric Blake wrote: > > - are marked as [MX] in POSIX [1][2][3][4], that is, an optional feature > > not contained in ISO C 99, > > [MX] means that the behavior is required on platforms that claim IEC > 60559 conformance (aka IEEE 754 format); it means that you fully > implement the otherwise-optional Appendix F of the C99 standard.
I see. Thanks for correcting me. Regarding DEC Alpha platforms, I don't think they are 100% IEEE 754 + 854 compliant, because the hardware designers took some shortcuts regarding the exception handling, in order to implement the floating-point operations in a single CPU cycle. > > - make little sense for 'ceil' from a mathematical point of view: > > ceil is a monotonically increasing function but POSIX wants > > ceil(-0.5) = 0.0 and ceil(-0.0) = -0.0, > > I'll raise that point with the Austin group. Given that the annex section F.9.6.1 in ISO C99 already specifies this behaviour, I don't think the Austin group will deviate from that. Bruno