On Wed, May 24, 2023, at 19:59, Zhangjin Wu wrote: > diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h > index c0335a84f880..00c7197dcd50 100644 > --- a/tools/include/nolibc/sys.h > +++ b/tools/include/nolibc/sys.h > @@ -1041,8 +1041,13 @@ int sys_select(int nfds, fd_set *rfds, fd_set > *wfds, fd_set *efds, struct timeva > struct timeval *t; > } arg = { .n = nfds, .r = rfds, .w = wfds, .e = efds, .t = timeout }; > return my_syscall1(__NR_select, &arg); > -#elif defined(__ARCH_WANT_SYS_PSELECT6) && defined(__NR_pselect6) > +#elif defined(__ARCH_WANT_SYS_PSELECT6) && (defined(__NR_pselect6) || > defined(__NR_pselect6_time64)) > +#ifdef __NR_pselect6 > struct timespec t; > +#else > + struct timespec64 t; > +#define __NR_pselect6 __NR_pselect6_time64 > +#endif Overriding the __NR_pselect6 constant seems wrong here, this can easily lead to more bugs, as pselect6 and pselect6_time64 are not compatible because of the different arguments, so anything using the constant after including sys.h will be broken. I would just use __kernel_timespec64 unconditionally and then use __NR_pselect6_time64 on all 32-bit architectures here, but use __NR_pselect6 on 32-bit architectures. I think we can also kill off the oldselect and newselect cases, using pselect6/pselect6_time64 unconditionally here, and no longer care about building against pre-5.1 kernel headers, at least for the copy of nolibc that ships with the kernel. Arnd