https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82207
--- Comment #12 from Steve Kargl <sgk at troutmask dot apl.washington.edu> --- On Wed, Jun 13, 2018 at 03:55:02PM +0000, guez at lmd dot ens.fr wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82207 > > --- Comment #11 from Lionel GUEZ <guez at lmd dot ens.fr> --- > And what about my suggestion that ieee_support_nan(0.) should return false for > the time being? > AFAIK, the original implementation for the IEEE support followed either the the F95 Floating-Point Exceptions Tecnical Report (ISO/EIC TR 15580:2001) or F2003. These refer to IEC 60599 (1989-01), aka IEEE 754-1985. Someone needs to review the entirety of the IEEE support with respect to the upcoming F2018 standard. F2018 refers to ISO/IEC/IEEE 60559:2011. I know that 60599:2011 is a significant revision to 60599 (1989-01). Unfortunately, there are not enough "someone"s to go around to fix gfortran. Given a very quick glance at F2003, I think that it may not be a good idea for ieee_support_nan(0.) to return .false. as this then means IEEE_IS_NAN(X) cannot be used to determine if X is a NaN.
