On older systems like SLES 11 without POSIX robust mutexes, but with glib robust mutexes where all the functions are available but have a "_np" suffix, compilation fails in:

ctdb/tests/src/test_mutex_raw.c.239.o: In function `worker':
/root/samba-4.10.6/bin/default/../../ctdb/tests/src/test_mutex_raw.c:129: undefined reference to `pthread_mutex_consistent'
ctdb/tests/src/test_mutex_raw.c.239.o: In function `main':
/root/samba-4.10.6/bin/default/../../ctdb/tests/src/test_mutex_raw.c:285: undefined reference to `pthread_mutex_consistent'
/root/samba-4.10.6/bin/default/../../ctdb/tests/src/test_mutex_raw.c:332: undefined reference to `pthread_mutexattr_setrobust'
/root/samba-4.10.6/bin/default/../../ctdb/tests/src/test_mutex_raw.c:363: undefined reference to `pthread_mutex_consistent'
collect2: ld returned 1 exit status

This happens because our pthreads shim include isn't included but the systems pthread.h directly. libreplace system/threads.h provides the required define

#if defined(HAVE_PTHREAD_MUTEX_CONSISTENT_NP) && \
!defined(HAVE_PTHREAD_MUTEX_CONSISTENT)
#define pthread_mutex_consistent pthread_mutex_consistent_np
#endif