test039 -b bdb, under watchmalloc so this in theory is The Actual Instruction:
(dbx) threads t@1 a l@1 ?() LWP suspended in __lwp_wait() t@2 a l@2 slapd_daemon_task() LWP suspended in _libc_poll() t@3 a l@3 ldap_int_thread_pool_wrapper() LWP suspended in attr_index_name_cmp() o> t@4 a l@4 ldap_int_thread_pool_wrapper() signal SIGSEGV in _ti_pthread_mutex_unlock() t@5 a l@5 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@6 a l@6 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@7 a l@7 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@8 a l@8 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@9 a l@9 ldap_int_thread_pool_wrapper() LWP suspended in match_re_C() t@10 a l@10 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@11 a l@11 ldap_int_thread_pool_wrapper() sleep on 0x10056ac10 in __lwp_park() t@12 a l@12 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@13 a l@13 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@14 a l@14 ldap_int_thread_pool_wrapper() sleep on 0xffffffff7f304650 in __lwp_park() t@15 a l@15 ldap_int_thread_pool_wrapper() LWP suspended in _ti_pthread_mutex_lock() t@16 a l@16 ldap_int_thread_pool_wrapper() sleep on 0x10053dcb0 in __lwp_park() t@17 a l@17 ldap_int_thread_pool_wrapper() LWP suspended in ordered_value_validate() t@18 a l@18 ldap_int_thread_pool_wrapper() LWP suspended in copy_pattern() (dbx) where current thread: t@4 [1] _ti_pthread_mutex_unlock(0x10053df90, 0x0, 0x0, 0x0, 0x0, 0x0), at 0xffffffff7dd1493c =>[2] ldap_pvt_thread_mutex_unlock(mutex = 0x10053df90), line 307 in "thr_posix.c" [3] ldap_back_getconn(op = 0x1005d0990, rs = 0xffffffff78bff998, sendok = 18, binddn = 0xffffffff78bfe5e8, bindcred = 0xffffffff78bfe5d8), line 912 in "bind.c" [4] ldap_back_dobind_int(lcp = 0xffffffff78bfe8f8, op = 0x1005d0990, rs = 0xffffffff78bff998, sendok = 18, retries = 0, dolock = 1), line 1267 in "bind.c" [5] ldap_back_dobind(lcp = 0xffffffff78bfe8f8, op = 0x1005d0990, rs = 0xffffffff78bff998, sendok = LDAP_BACK_SENDERR), line 1508 in "bind.c" [6] ldap_back_search(op = 0x1005d0990, rs = 0xffffffff78bff998), line 166 in "search.c" [7] glue_sub_search(op = 0x1005d0990, rs = 0xffffffff78bff998, b0 = 0xffffffff78bfeda8, on = 0x1005389e0), line 340 in "backglue.c" [8] glue_op_search(op = 0x1005d0990, rs = 0xffffffff78bff998), line 452 in "backglue.c" [9] overlay_op_walk(op = 0x1005d0990, rs = 0xffffffff78bff998, which = op_search, oi = 0x100538800, on = 0x1005389e0), line 642 in "backover.c" [10] over_op_func(op = 0x1005d0990, rs = 0xffffffff78bff998, which = op_search), line 704 in "backover.c" [11] over_op_search(op = 0x1005d0990, rs = 0xffffffff78bff998), line 726 in "backover.c" [12] fe_op_search(op = 0x1005d0990, rs = 0xffffffff78bff998), line 368 in "search.c" [13] overlay_op_walk(op = 0x1005d0990, rs = 0xffffffff78bff998, which = op_search, oi = 0x10053c6b0, on = (nil)), line 652 in "backover.c" [14] over_op_func(op = 0x1005d0990, rs = 0xffffffff78bff998, which = op_search), line 704 in "backover.c" [15] over_op_search(op = 0x1005d0990, rs = 0xffffffff78bff998), line 726 in "backover.c" [16] do_search(op = 0x1005d0990, rs = 0xffffffff78bff998), line 217 in "search.c" [17] connection_operation(ctx = 0xffffffff78bffc28, arg_v = 0x1005d0990), line 1083 in "connection.c" [18] connection_read_thread(ctx = 0xffffffff78bffc28, argv = 0xd), line 1210 in "connection.c" [19] ldap_int_thread_pool_wrapper(xpool = 0x1004f2ad0), line 625 in "tpool.c"
I can tar up the testrun directory (or the entire source tree) if interested.