Re: [PATCH] Fix __clock_gettime64 with _ISOMAC in sysdeps/generic/hp-timing.h

[Florian Weimer via Libc-alpha <libc-alpha@sourceware.org>]

* H. J. Lu:

> On Thu, May 28, 2020 at 5:58 AM Florian Weimer <fweimer@redhat.com> wrote:
>>
>> * H. J. Lu via Libc-alpha:
>>
>> > diff --git a/sysdeps/generic/hp-timing.h b/sysdeps/generic/hp-timing.h
>> > index af9d92f7f7..99b12995f1 100644
>> > --- a/sysdeps/generic/hp-timing.h
>> > +++ b/sysdeps/generic/hp-timing.h
>> > @@ -24,6 +24,11 @@
>> >  #include <stdint.h>
>> >  #include <hp-timing-common.h>
>> >
>> > +#ifdef _ISOMAC
>> > +# define __timespec64 timespec
>> > +# define __clock_gettime64 clock_gettime
>> > +#endif
>> > +
>> >  /* It should not be used for ld.so.  */
>> >  #define HP_TIMING_INLINE     (0)
>>
>> To be honest, I would have expected different definitions of the timing
>> macros.  This redirection looks a bit iffy for me for _ISOMAC.
>
> What do you have in mind?

Something like this:

/* The clock_gettime (CLOCK_MONOTONIC) has unspecified starting time,
   nano-second accuracy, and for some architectues is implemented as
   vDSO symbol.  */
#ifdef _ISOMAC
# define HP_TIMING_NOW(var) \
({								\
  struct timespec tv;						\
  clock_gettime (CLOCK_MONOTONIC, &tv);				\
  (var) = (tv.tv_nsec + UINT64_C(1000000000) * tv.tv_sec);	\
})
#else
# define HP_TIMING_NOW(var) \
({								\
  struct __timespec64 tv;					\
  __clock_gettime64 (CLOCK_MONOTONIC, &tv);			\
  (var) = (tv.tv_nsec + UINT64_C(1000000000) * tv.tv_sec);	\
})
#endif

in sysdeps/generic/hp-timing.h.

Thanks,
Florian