Re: [PATCH] time: Skip overflow itimer tests on 32-bit systems

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 07/06/2021 10:18, Stafford Horne wrote:
> On the port of OpenRISC I am working on and it appears the rv32 port
> we have sets __TIMESIZE == 64 && __WORDSIZE == 32.  This causes the
> size of time_t to be 8 bytes, but the tv_sec in the kernel is still 32-bit
> causing truncation.
> 
> The truncations are unavoidable on these systems so skip the
> testing/failures by guarding with __KERNEL_OLD_TIMEVAL_MATCHES_TIMEVAL64.

Sigh, I was hoping that we won't need to handle this situation (glibc 
support only 64-bit time_t, but kernel still providing some 32-bit 
syscall).

> ---
> 
> I am open to other suggestions, this seemed the most correct to me.
> 
> Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
> Cc: Alistair Francis <alistair.francis@wdc.com>
> 
>  time/tst-itimer.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/time/tst-itimer.c b/time/tst-itimer.c
> index 929c2b74c7..0c99d46d7e 100644
> --- a/time/tst-itimer.c
> +++ b/time/tst-itimer.c
> @@ -89,6 +89,7 @@ do_test (void)
>        TEST_COMPARE (it.it_interval.tv_sec, it_old.it_interval.tv_sec);
>        TEST_COMPARE (it.it_interval.tv_usec, it_old.it_interval.tv_usec);
>  
> +#if __KERNEL_OLD_TIMEVAL_MATCHES_TIMEVAL64
>        if (sizeof (time_t) == 4)
>  	continue;
>  
> @@ -146,6 +147,7 @@ do_test (void)
>  	  TEST_COMPARE (setitimer (timers[i], &it, NULL), -1);
>  	  TEST_COMPARE (errno, EOVERFLOW);
>  	}
> +#endif
>    }
>  
>    {
> 

Instead of disabling, I think it would be better to use
__KERNEL_OLD_TIMEVAL_MATCHES_TIMEVAL64 instead of __time_t sizeof
(so we can still tests the EOVERFLOW):

diff --git a/time/tst-itimer.c b/time/tst-itimer.c
index 929c2b74c7..bd7d7afe83 100644
--- a/time/tst-itimer.c
+++ b/time/tst-itimer.c
@@ -100,7 +100,7 @@ do_test (void)

       /* Linux does not provide 64 bit time_t support for getitimer and
         setitimer on architectures with 32 bit time_t support.  */
-      if (sizeof (__time_t) == 8)
+      if (__KERNEL_OLD_TIMEVAL_MATCHES_TIMEVAL64)
        { 
          TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
          TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 },
@@ -131,7 +131,7 @@ do_test (void)
       it.it_interval.tv_usec = 20;
       it.it_value.tv_sec = 30;
       it.it_value.tv_usec = 40;
-      if (sizeof (__time_t) == 8)
+      if (__KERNEL_OLD_TIMEVAL_MATCHES_TIMEVAL64)
        { 
          TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);