https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94087
--- Comment #18 from rguenther at suse dot de <rguenther at suse dot de> --- On Thu, 14 May 2020, hjl.tools at gmail dot com wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94087 > > --- Comment #15 from H.J. Lu <hjl.tools at gmail dot com> --- > (In reply to Jonathan Wakely from comment #13) > > We could do this easily enough (which could be simplified if RDRAND is > > guaranteed to be available when RDSEED is available): > > > > All Intel processors with RDSEED supports RDRAND which requires checking > of the CF bit in EFLAGS. Note in virtualized environments support for RDRAND might be disabled while RDSEED is enabled(?) even if no such hardware configuration exists [by now]. If I were a chip manufacturer (hello VIA?) that at the moment neither implements RDRAND nor RDSEED a good option would be to only go for the stronger RDSEED and leave RDRAND unimplemented.
