On 2023-08-12 20:26, Po Lu wrote:

> In file included from boot-time.c:54:0:
> boot-time-aux.h: In function 'get_linux_uptime':
> boot-time-aux.h:70:3: error: implicit declaration of function 'sysinfo' [-Werror=implicit-function-declaration]
>     if (sysinfo (&info) >= 0)
>     ^
> boot-time.c: In function 'get_boot_time_uncached':
> boot-time.c:111:26: error: 'BOOT_TIME' undeclared (first use in this function)
>         if (ut->ut_type == BOOT_TIME)
>                            ^
> boot-time.c:111:26: note: each undeclared identifier is reported only once for each function it appears in
> boot-time.c:126:3: error: implicit declaration of function 'endutent' [-Werror=implicit-function-declaration]
>     END_UTMP_ENT ();
>     ^
> cc1: some warnings being treated as errors

Thanks for reporting that. As I understand it, the utmp/utmpx functions 
are a losing cause on Android since they never return anything. If so, 
it's simpler to bypass these functions on that platform. Also, Gnulib 
should bypass sysinfo unless it's available. Please try the attached 
patch, which I haven't installed onto Emacs master on Savannah. I've 
tested it only on Ubuntu 23.04.

If this patch works we can propagate it to Gnulib.