On Tue, 20 Jun 2023, Yonggang Luo via Libc-alpha wrote: > +#ifdef __GLIBC_USE_ISOC23 > +#define TIME_MONOTONIC 2 The only standard values new in C2x are TIME_MONOTONIC, TIME_ACTIVE and TIME_THREAD_ACTIVE. All others should probably be conditioned on __USE_GNU if defined at all. -- Joseph S. Myers joseph@codesourcery.com