bug#64937: "who" reports funny dates

[Thorsten Kukuk]

Hi,

currently testing current coreutils git checkout on a utmp/wtmp free
machine, looks good so far. Except there is a compile problem with this
patch:

On Tue, Aug 08, Bruno Haible wrote:

> 2023-08-08  Bruno Haible  <bruno@clisp.org>
> 
>       readutmp: Get the boot time with higher precision.
>       Suggested by Thorsten Kukuk <kukuk@suse.com> in
>       
> <https://github.com/thkukuk/utmpx/blob/main/utmp-to-logind.md#determine-boot-time>.
>       * lib/readutmp.c (get_boot_time_uncached): Try clock_gettime first.
> 
> diff --git a/lib/readutmp.c b/lib/readutmp.c
> index 7ef5bfe84c..f7e43eb4a6 100644
> --- a/lib/readutmp.c
> +++ b/lib/readutmp.c
> @@ -284,6 +284,31 @@ finish_utmp (struct utmp_alloc a)
>  static struct timespec
>  get_boot_time_uncached (void)
>  {
> +  /* The clock_gettime facility returns the uptime with a resolution of 1 
> µsec.
> +     It is available with glibc >= 2.14.  In glibc < 2.17 it required linking
> +     with librt.  */
> +#  if __GLIBC__ + (__GLIBC_MINOR__ >= 17) > 2
> +  struct timespec up;

Not sure how relevant this code still is, but currently I get with this:

lib/readutmp.c: In function 'get_boot_time_uncached':
lib/readutmp.c:326:35: error: declaration of 'up' shadows a previous local 
[-Werror=shadow]
  326 |                   struct timespec up =
      |                                   ^~
lib/readutmp.c:286:19: note: shadowed declaration is here
  286 |   struct timespec up;
      |                   ^~
cc1: all warnings being treated as errors


  Thorsten

-- 
Thorsten Kukuk, Distinguished Engineer, Senior Architect, Future Technologies
SUSE Software Solutions Germany GmbH, Frankenstraße 146, 90461 Nuernberg, 
Germany
Managing Director: Ivo Totev, Andrew McDonald, Werner Knoblich
(HRB 36809, AG Nürnberg)