npth finds pthread_mutex_timedlock() which android does not have

[Marcus Brinkmann]

On 02/20/2012 09:07 PM, Hans-Christoph Steiner wrote:
>
> Apparently, Android's NDK defines pthread_mutex_timedlock() in the
> headers but then does not implement it.  And it seems they aren't close
> to implementing it:
> http://code.google.com/p/android/issues/detail?id=2138
>
> This is of course a really crappy situation since it means that you
> can't do simple things like AC_CHECK_FUNCS([pthread_mutex_timedlock])
> because that actually finds the function.

Actually, are you sure?  I set up cross build environments for 
android-8, -9 and -14, and it seems to work as expected:

android-8:

checking for library containing pthread_create... none required
checking for pthread_tryjoin_np... no
checking for pthread_setname_np... no
checking for pthread_getname_np... no
checking for pthread_mutex_timedlock... no
checking for pthread_rwlock_rdlock... no
checking for pthread_rwlock_wrlock... no
checking for pthread_rwlock_timedrdlock... no
checking for pthread_rwlock_timedwrlock... no
checking for pthread_rwlock_tryrdlock... no
checking for pthread_rwlock_trywrlock... no

android-9 and -14 (sorry, not the output, just the config.log):

ac_cv_func_pthread_getname_np=no
ac_cv_func_pthread_mutex_timedlock=no
ac_cv_func_pthread_rwlock_rdlock=yes
ac_cv_func_pthread_rwlock_timedrdlock=yes
ac_cv_func_pthread_rwlock_timedwrlock=yes
ac_cv_func_pthread_rwlock_tryrdlock=yes
ac_cv_func_pthread_rwlock_trywrlock=yes
ac_cv_func_pthread_rwlock_wrlock=yes
ac_cv_func_pthread_setname_np=yes
ac_cv_func_pthread_tryjoin_np=no

And this makes sense, because AC_CHECK_FUNCS does not look at the header 
file, but if linking with the symbol works.

The compile errors you get are due to the fact that these functions were 
used unconditionally in npth.

I am going to work on replacement functions, but I want to make sure I 
am not missing something that makes AC_CHECK_FUNC fail for you.

Thanks,
Marcus