Re: AC_SYS_LARGEFILE_REQUIRED vs. AC_SYS_YEAR2038_REQUIRED on MSVC

[Adhemerval Zanella]

> On 16 Apr 2023, at 12:28, Bruno Haible <bruno@clisp.org> wrote:
> 
> I presented the test results:
>>  - hello-3: no gnulib, just AC_SYS_LARGEFILE_REQUIRED
>>  - hello-4: no gnulib, just AC_SYS_YEAR2038_REQUIRED
>>  - testdir3: a gnulib testdir for the modules largefile-required stat
>>  - testdir4: a gnulib testdir for the modules year2038-required stat
>> 
>>             mingw64  mingw32  msvc64  msvc32
>> 
>> hello-3        OK       OK     "support not detected" -> fail
>> hello-4        OK       OK     "support not detected" -> fail
>> testdir3       OK       OK       OK      OK
>> testdir4       OK       OK       OK      OK
> 
> Now, one could argue that in the above table the outcome should be:
> 
>             mingw64  mingw32  msvc64  msvc32
> 
> hello-3        OK       OK     "support not detected" -> fail
> hello-4        OK       OK       OK      OK
> testdir3       OK       OK       OK      OK
> testdir4       OK       OK       OK      OK
> 
> since in hello-4 the maintainer has only asked for year 2038
> support, not for large files support. And the dependency from year 2038
> support to large files support exists only in glibc (since the glibc
> developers found it pointless to add a 'struct stat' variant with
> 32-bit off_t and 64-bit time_t).

It is pointless indeed, it would require another 4 compat symbols with extra 
translation layer, further complexity for symbol redirection, and even more 
testing to check for any broken state (as we found while testing some some 
specific architectures).