Notice a segfault when running some test (unrelated to mongo)

(gdb) bt
#0 0x00007ffff4af2b3a in strlen () from /lib64/libc.so.6
#1 0x00007ffff4ae080f in fputs_unlocked () from /lib64/libc.so.6
#2 0x00007ffff4b63e45 in __vsyslog_chk () from /lib64/libc.so.6
#3 0x00007ffff4b64362 in __syslog_chk () from /lib64/libc.so.6
#4 0x00007fffecc51863 in _sasl_syslog () from /lib64/libsasl2.so.3
#5 0x00007fffecc5341f in _sasl_log () from /lib64/libsasl2.so.3
#6 0x00007fffdeef4b2a in digestmd5_common_mech_free () from /usr/lib64/sasl2/libdigestmd5.so
#7 0x00007fffecc4fca9 in client_done () from /lib64/libsasl2.so.3
#8 0x00007fffecc4fdea in sasl_client_done () from /lib64/libsasl2.so.3
#9 0x00007fffeca15bfe in _mongoc_do_cleanup () from /lib64/libmongoc-priv.so.0
#10 0x00007ffff43c20e9 in __pthread_once_slow () from /lib64/libpthread.so.0
#11 0x00007fffece8276d in zm_shutdown_mongodb (type=<optimized out>, module_number=16) at /usr/src/debug/php-pecl-mongodb-1.1.5/NTS/php_phongo.c:2554
#12 0x000055555579b737 in module_destructor (module=0x555555c07b60) at /usr/src/debug/php-5.6.20/Zend/zend_API.c:2376
#13 0x00005555557a0d06 in i_zend_hash_bucket_delete (p=0x555555c07b00, ht=0x555555b9a260 <module_registry>) at /usr/src/debug/php-5.6.20/Zend/zend_hash.c:182
#14 zend_hash_bucket_delete (ht=ht@entry=0x555555b9a260 <module_registry>, p=0x555555c07b00) at /usr/src/debug/php-5.6.20/Zend/zend_hash.c:192
#15 0x00005555557a2508 in zend_hash_graceful_reverse_destroy (ht=0x555555b9a260 <module_registry>) at /usr/src/debug/php-5.6.20/Zend/zend_hash.c:613
#16 0x000055555579a02c in zend_destroy_modules () at /usr/src/debug/php-5.6.20/Zend/zend_API.c:1894
#17 0x0000555555793aff in zend_shutdown () at /usr/src/debug/php-5.6.20/Zend/zend.c:836
#18 0x000055555573021b in php_module_shutdown () at /usr/src/debug/php-5.6.20/main/main.c:2477
#19 0x000055555560f810 in main (argc=7, argv=0x555555bb0150) at /usr/src/debug/php-5.6.20/sapi/cli/php_cli.c:1393