SEGV while running t/spec/S17-promise/nonblocking-await.t

gistfile1.txt

[New Thread 0xb31fcb40 (LWP 16195)]
ok 1 - Recursion creating a deep await-tree completes correctly
    1..3
    ok 1 - code dies
    ok 2 - right exception type (Exception)
    ok 3 - .message matches oopsy
ok 2 - Deep Promise tree conveys exception up to the top
[New Thread 0xb0ffab40 (LWP 16196)]
ok 3 - Hundreds of time-based Promises awaited completes correctly
ok 4 - await of multiple Promises suspends until all ready
ok 5 - Hundred of await on time/manual Promise completes corectly
ok 6 - await of multiple Promises suspends until all ready
    1..3
    ok 1 - code dies
    ok 2 - right exception type (X::AdHoc)
    ok 3 - .message matches bust
ok 7 - Multiple await also conveys errors correctly
ok 8 - Hundred of outstanding awaits on supplies works
    1..3
    ok 1 - code dies
    ok 2 - right exception type (Exception)
    ok 3 - .message matches strewth
ok 9 - Hundred of outstanding awaits on supplies that die works
ok 10 - Hundred of outstanding awaits on channels works

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb3dfeb40 (LWP 16194)]
0x00000000 in ?? ()
(gdb) bt
#0  0x00000000 in ?? ()
#1  0xb7c6977a in MVM_repr_elems (tc=tc@entry=0xb421d868, obj=obj@entry=0xb7b6e478 <main_arena+88>) at src/6model/reprconv.c:496
#2  0xb7c6d1db in MVM_6model_parametric_try_find_parameterization (tc=tc@entry=0xb421d868, st=st@entry=0x8e7ae40, params=params@entry=0xb3e087c0) at src/6model/parametric.c:103
#3  0xb7c6d31b in MVM_6model_parametric_parameterize (tc=0xb421d868, type=0x8e7f2d8, params=0xb3e087c0, result=0xb24252f0) at src/6model/parametric.c:74
#4  0xb7c25f9a in MVM_interp_run (tc=tc@entry=0xb421d868, initial_invoke=initial_invoke@entry=0xb7c3ea90 <thread_initial_invoke>, invoke_data=0xb421d868) at src/core/interp.c:4412
#5  0xb7c3ea52 in start_thread (data=0xb42144f8) at src/core/threads.c:80
#6  0xb7d1ebf8 in uv__thread_start (arg=0xb420a4e8) at 3rdparty/libuv/src/unix/thread.c:49
#7  0xb7966f72 in start_thread (arg=0xb3dfeb40) at pthread_create.c:312
#8  0xb7aaef8e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:129
(gdb) f 3
#3  0xb7c6d31b in MVM_6model_parametric_parameterize (tc=0xb421d868, type=0x8e7f2d8, params=0xb3e087c0, result=0xb24252f0) at src/6model/parametric.c:74
74	    found = MVM_6model_parametric_try_find_parameterization(tc, st, params);
(gdb) p MVM_dump_backtrace(tc)
   at <unknown>:1  (./blib/Perl6/Metamodel.moarvm:mixin)
 from SETTING::src/core/operators.pm:65  (./CORE.setting.moarvm:infix:<but>)
 from SETTING::src/core.d/await.pm:24  (./CORE.d.setting.moarvm:)
 from SETTING::src/core.d/await.pm:23  (./CORE.d.setting.moarvm:)
 from <unknown>:1  (./CORE.d.setting.moarvm:)
 from SETTING::src/core/Exception.pm:66  (./CORE.setting.moarvm:rethrow)
 from SETTING::src/core/ThreadPoolScheduler.pm:33  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:18  (./CORE.setting.moarvm:await)
 from SETTING::src/core.d/await.pm:27  (./CORE.d.setting.moarvm:await)
 from t/spec/S17-promise/nonblocking-await.t:121  (<ephemeral file>:)
 from SETTING::src/core/Promise.pm:216  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:284  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:167  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:29  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:167  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:165  (./CORE.setting.moarvm:)
 from SETTING::src/core/ThreadPoolScheduler.pm:163  (./CORE.setting.moarvm:)
 from SETTING::src/core/Thread.pm:30  (./CORE.setting.moarvm:THREAD-ENTRY)
$1 = void