[LTP] [PATCH v2] sigrelse01: Check if signal 34 is available for musl compat

[Florian Schmaus]

On 13/08/2025 17.26, Pedro Falcato wrote:
> On Fri, Aug 08, 2025 at 06:34:57PM +0200, Florian Schmaus via ltp wrote:
>> Do not select signal 34 when the test is run using musl. Signal 34 is
>> used internally by musl as SIGSYNCCALL. Consequently, musl's signal()
>> will return with an error status and errno set to EINVAL when trying
>> to setup a signal handler for signal 34, causing the sigrelse01 test
>> to fail.
>>
>> Since musl provides no preprocessor macro, we check for the
>> availability of signal 34 by attempting to setup a signal handler. If
>> signal() returns SIG_ERR with errno set to EINVAL then we assume the
>> signal is unavailable. Knowing signal 34 is available with glibc, we
>> perform this check only if __GLIBC__ is not defined.
>>
> 
 > […]
 >
> So, the correct fix would be to exclude all signals outside of [SIGRTMIN, SIGRTMAX]

Thanks, this does the trick and reduces the size of the patch 
significantly. Will send v3 shortly.

- Florian