Re: [PATCH] linux: Make tst-mount-consts unsupported for kernels headers older than 5.0

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 10/08/22 06:18, Florian Weimer wrote:
> * Adhemerval Zanella:
> 
>> The linux/mount.h is only provided by Linux 5.0.
>>
>> Checked on x86_64-linux-gnu.
>> ---
>>  sysdeps/unix/sysv/linux/tst-mount-consts.py | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/sysdeps/unix/sysv/linux/tst-mount-consts.py b/sysdeps/unix/sysv/linux/tst-mount-consts.py
>> index 4fb356310b..0f5b982430 100755
>> --- a/sysdeps/unix/sysv/linux/tst-mount-consts.py
>> +++ b/sysdeps/unix/sysv/linux/tst-mount-consts.py
>> @@ -34,6 +34,9 @@ def main():
>>      args = parser.parse_args()
>>  
>>      linux_version_headers = glibcsyscalls.linux_kernel_version(args.cc)
>> +    # Linux started to provide mount.h with 5.0.
>> +    if linux_version_headers < (5, 0):
>> +        sys.exit (77)
>>      # Constants in glibc were updated to match Linux v5.19.  When glibc
>>      # constants are updated this value should be updated to match the
>>      # released kernel version from which the constants were taken.
> 
> Should this use compile_c_snippet from the other patch?

It is strategy already used on tst-pidfd-consts.py.  Not sure if syscalls 
backport to old releases is that common (it seems that we recently had to
handle it for memfd_secret), but we do not usually take this in consideration
on the __ASSUME macros and optimizations.