gistfile1.txt

# terminal window 1
dogbert@dogbert-VirtualBox:~/repos/rakudo$ ASAN_OPTIONS="detect_leaks=0" MVM_SPESH_NODELAY=1 make t/09-moar/01-profilers.t
+++ Checking for moar NQP version
'/usr/bin/perl' -I'/home/dogbert/repos/rakudo/tools/lib' -I'/home/dogbert/repos/rakudo/3rdparty/nqp-configure/lib' t/harness5 --moar --fudge --keep-exit-code --verbosity=1 t/09-moar/01-profilers.t

ok 1 - can launch with profiling requested
ok 2 - profiler html output file exists on disk
ok 3 - profiler html output file isn't tiny
<hung !!>

# terminal window 2, connect gdb to process
dogbert@dogbert-VirtualBox:~$ sudo gdb -p 1625259
[sudo] password for dogbert:         
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Attaching to process 1625259
[New LWP 1625260]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x61e00000047c) at ../sysdeps/nptl/futex-internal.h:183
183	../sysdeps/nptl/futex-internal.h: No such file or directory.
(gdb) info threads
  Id   Target Id                                             Frame 
* 1    Thread 0x7f70d9975bc0 (LWP 1625259) "moar"            futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x61e00000047c) at ../sysdeps/nptl/futex-internal.h:183
  2    Thread 0x7f70d6cac700 (LWP 1625260) "spesh optimizer" futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x61e000000160) at ../sysdeps/nptl/futex-internal.h:183
(gdb) bt
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x61e00000047c) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x61e000000428, cond=0x61e000000450) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x61e000000450, mutex=0x61e000000428) at pthread_cond_wait.c:647
#3  0x00007f70da8bddbd in uv_cond_wait () from //home/dogbert/repos/rakudo/nqp/MoarVM/../../install/lib/libmoar.so
#4  0x00007f70da7faae3 in MVM_profile_start (tc=0x618000000080, config=0x63200000a680) at src/profiler/profile.c:33
#5  0x00007f70da46a810 in MVM_interp_run (tc=0x61e00000047c, initial_invoke=0x80, invoke_data=0x7ffe06e123c0, outer_runloop=0x7f70d9af3376 <__pthread_cond_wait+534>) at src/core/interp.c:4149
#6  0x00005621edcd8c8c in main (argc=<optimized out>, argv=<optimized out>) at src/main.c:307
(gdb) f 3
#3  0x00007f70da8bddbd in uv_cond_wait () from //home/dogbert/repos/rakudo/nqp/MoarVM/../../install/lib/libmoar.so
(gdb) l
178	in ../sysdeps/nptl/futex-internal.h
(gdb) f 4
#4  0x00007f70da7faae3 in MVM_profile_start (tc=0x618000000080, config=0x63200000a680) at src/profiler/profile.c:33
33	                uv_cond_wait(&(tc->instance->cond_spesh_sync), &(tc->instance->mutex_spesh_sync));
(gdb) l
28	            tc->instance->profiling_overhead = (MVMuint64) ((e - s) / 1000) * 0.9;
29	
30	            /* Disable profiling and discard the data we just collected. */
31	            uv_mutex_lock(&(tc->instance->mutex_spesh_sync));
32	            while (tc->instance->spesh_working != 0)
33	                uv_cond_wait(&(tc->instance->cond_spesh_sync), &(tc->instance->mutex_spesh_sync));
34	            tc->instance->profiling = 0;
35	            MVM_free_null(tc->prof_data->collected_data);
36	
37	            MVM_profile_instrumented_free_data(tc);
(gdb) t 2
[Switching to thread 2 (Thread 0x7f70d6cac700 (LWP 1625260))]
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x61e000000160) at ../sysdeps/nptl/futex-internal.h:183
183	../sysdeps/nptl/futex-internal.h: No such file or directory.
(gdb) bt
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x61e000000160) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x61e000000108, cond=0x61e000000138) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x61e000000138, mutex=0x61e000000108) at pthread_cond_wait.c:647
#3  0x00007f70da8bddbd in uv_cond_wait () from //home/dogbert/repos/rakudo/nqp/MoarVM/../../install/lib/libmoar.so
#4  0x00007f70da516780 in MVM_gc_enter_from_allocator (tc=tc@entry=0x618000000880) at src/gc/orchestrate.c:561
#5  0x00007f70da517281 in MVM_gc_allocate_nursery (tc=0x618000000880, size=240) at src/gc/allocation.c:37
#6  0x00007f70da518270 in MVM_gc_allocate (size=<optimized out>, tc=0x618000000880) at src/gc/allocation.c:94
#7  MVM_gc_allocate_zeroed (size=<optimized out>, tc=0x618000000880) at src/gc/allocation.h:21
#8  MVM_gc_allocate_object (tc=0x618000000880, st=<optimized out>) at src/gc/allocation.c:86
#9  0x00007f70da5720a6 in MVM_repr_alloc_init (tc=tc@entry=0x618000000880, type=<optimized out>) at src/6model/reprconv.c:17
#10 0x00007f70da722a6d in MVM_spesh_candidate_add (tc=tc@entry=0x618000000880, p=0x625002f28c60) at src/6model/reprs/MVMSpeshCandidate.c:269
#11 0x00007f70da705230 in worker (tc=0x618000000880, arg_info=...) at src/spesh/worker.c:29
#12 0x00007f70da4b42c8 in thread_initial_invoke (tc=0x618000000880, data=<optimized out>) at src/core/threads.c:68
#13 0x00007f70da41bb0a in MVM_interp_run (tc=0x61e000000160, tc@entry=0x618000000880, initial_invoke=0x80, initial_invoke@entry=0x7f70da4b4150 <thread_initial_invoke>, invoke_data=0x602000000af0, 
    outer_runloop=0x7f70d9af3376 <__pthread_cond_wait+534>, outer_runloop@entry=0x0) at src/core/interp.c:180
#14 0x00007f70da4b457a in start_thread (data=0x602000000af0) at src/core/threads.c:101
#15 0x00007f70d9aec609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#16 0x00007f70d9c39293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb)