[libc] Implement 64bit time_t and localtime

[zimirza]

It might be good to implement a 64bit time_t and localtime/localtime_s. According to https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/localtime-localtime32-localtime64, these are defined as:

struct tm *localtime( const time_t *sourceTime );
struct tm *_localtime32( const __time32_t *sourceTime );
struct tm *_localtime64( const __time64_t *sourceTime );

It would be good to be consistent for compatibility reasons.

This should be implemented after #110363 gets merged and #107597 is completed.

[llvmbot]

@llvm/issue-subscribers-libc

Author: Зишан Мирза (zimirza)

It might be good to implement a 64bit `time_t` and `localtime`/`localtime_s`. According to https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/localtime-localtime32-localtime64, these are defined as:

struct tm *localtime( const time_t *sourceTime );
struct tm *_localtime32( const __time32_t *sourceTime );
struct tm *_localtime64( const __time64_t *sourceTime );

It would be good to be consistent for compatibility reasons.

This should be implemented after #110363 gets merged and #107597 is completed.