[PATCH] y2038: Introduce __ASSUME_TIME64_SYSCALLS define

[Joseph Myers]

On Wed, 8 May 2019, Lukasz Majewski wrote:

> For x32 this flag is explicitly undefined as this architecture has
> 64 bit registers but only 32 bit longs and pointers. Moreover, it uses
> syscalls from x86_64.

The first sentence there is not an accurate description of the reason for 
undefining this for x32; other ILP32 configurations with 64-bit registers 
don't have this peculiarity.  "Moreover, it uses syscalls from x86_64." 
isn't a good description either; x86_64 has three syscall tables (for 
32-bit compat, x32 and the normal LP64 syscall interface).

> +   Linux kernel, as of version 5.1, provides following set of syscalls,
> +   which accept data based on struct timespec and timeval with 64 bit
> +   tv_sec:

Do any of these actually use timeval?  I thought the idea was that the new 
syscalls for 64-bit time would all use timespec, with it being the 
responsibility of libc to handle conversions to and from timeval as needed 
(e.g. for gettimeofday with _TIME_BITS=64).

-- 
Joseph S. Myers
joseph@codesourcery.com