Fishy stuff when running Zoffix 'golf'

gistfile1.txt

ogbert@dogbert-VirtualBox ~/repos/rakudo $ gdb /home/dogbert/repos/rakudo/install/bin/moar core
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Reading symbols from /home/dogbert/repos/rakudo/install/bin/moar...done.
[New LWP 4298]
[New LWP 4303]
[New LWP 4302]
[New LWP 4304]
[New LWP 4299]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `/home/dogbert/repos/rakudo/nqp/MoarVM/../../install/bin/moar --execname=./perl6'.
Program terminated with signal SIGABRT, Aborted.
#0  0x00007f2008f29428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
54	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
[Current thread is 1 (Thread 0x7f2009ed0700 (LWP 4298))]
(gdb) info threads
  Id   Target Id         Frame 
* 1    Thread 0x7f2009ed0700 (LWP 4298) 0x00007f2008f29428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
  2    Thread 0x7f2004e2b700 (LWP 4303) 0x00007f2008fc030d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
  3    Thread 0x7f200562c700 (LWP 4302) 0x00007f20094fab74 in MVM_gc_gen2_allocate (al=0x431f4b0, size=40) at src/gc/gen2.c:78
  4    Thread 0x7f1ff7fff700 (LWP 4304) pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
  5    Thread 0x7f20081c0700 (LWP 4299) pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
(gdb) bt
#0  0x00007f2008f29428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1  0x00007f2008f2b02a in __GI_abort () at abort.c:89
#2  0x00007f2008f21bd7 in __assert_fail_base (fmt=<optimized out>, assertion=assertion@entry=0x7f2009655138 "*item_ptr != item->sc_forward_u.forwarder", file=file@entry=0x7f2009655121 "src/gc/collect.c", 
    line=line@entry=218, function=function@entry=0x7f20096552e0 <__PRETTY_FUNCTION__.15986> "process_worklist") at assert.c:92
#3  0x00007f2008f21c82 in __GI___assert_fail (assertion=0x7f2009655138 "*item_ptr != item->sc_forward_u.forwarder", file=0x7f2009655121 "src/gc/collect.c", line=218, 
    function=0x7f20096552e0 <__PRETTY_FUNCTION__.15986> "process_worklist") at assert.c:101
#4  0x00007f20094f8465 in process_worklist (tc=0x12d1a20, worklist=0x416da90, wtp=0x7fffe28d3ab0, gen=0 '\000') at src/gc/collect.c:218
#5  0x00007f20094f82f6 in MVM_gc_collect (tc=0x12d1a20, what_to_do=0 '\000', gen=0 '\000') at src/gc/collect.c:157
#6  0x00007f20094f2886 in run_gc (tc=0x12d1a20, what_to_do=0 '\000') at src/gc/orchestrate.c:407
#7  0x00007f20094f2cf5 in MVM_gc_enter_from_allocator (tc=0x12d1a20) at src/gc/orchestrate.c:524
#8  0x00007f20094f3476 in MVM_gc_allocate_nursery (tc=0x12d1a20, size=184) at src/gc/allocation.c:32
#9  0x00007f20094f3283 in MVM_gc_allocate (tc=0x12d1a20, size=184) at src/gc/allocation.h:13
#10 0x00007f20094f34f6 in MVM_gc_allocate_zeroed (tc=0x12d1a20, size=184) at src/gc/allocation.c:49
#11 0x00007f20094f375e in MVM_gc_allocate_frame (tc=0x12d1a20) at src/gc/allocation.c:99
#12 0x00007f20094bdbf6 in allocate_frame (tc=0x12d1a20, static_frame=0x2215b78, spesh_cand=0x7f2000090400, heap=1) at src/core/frame.c:247
#13 0x00007f20094be710 in MVM_frame_invoke (tc=0x12d1a20, static_frame=0x2215b78, callsite=0x7f2009bb9fe0 <inv_arg_callsite>, args=0x2808828, outer=0x4a426e0, code_ref=0x488b318, spesh_cand=0)
    at src/core/frame.c:491
#14 0x00007f20094b48bb in MVM_interp_run (tc=0x12d1a20, initial_invoke=0x7f20095f55e3 <toplevel_initial_invoke>, invoke_data=0x134d0e0) at src/core/interp.c:5501
#15 0x00007f20095f5748 in MVM_vm_run_file (instance=0x12d1010, filename=0x7fffe28d628f "/home/dogbert/repos/rakudo/perl6.moarvm") at src/moar.c:407
#16 0x0000000000401797 in main (argc=9, argv=0x7fffe28d5538) at src/main.c:299
(gdb) t 3
[Switching to thread 3 (Thread 0x7f200562c700 (LWP 4302))]
#0  0x00007f20094fab74 in MVM_gc_gen2_allocate (al=0x431f4b0, size=40) at src/gc/gen2.c:78
78	            result = (void *)al->size_classes[bin].free_list;
(gdb) bt
#0  0x00007f20094fab74 in MVM_gc_gen2_allocate (al=0x431f4b0, size=40) at src/gc/gen2.c:78
#1  0x00007f20094f85e2 in process_worklist (tc=0x431f1b0, worklist=0x7f1ff93773d0, wtp=0x7f200562a7c0, gen=0 '\000') at src/gc/collect.c:273
#2  0x00007f20094f8321 in MVM_gc_collect (tc=0x431f1b0, what_to_do=1 '\001', gen=0 '\000') at src/gc/collect.c:163
#3  0x00007f20094f2886 in run_gc (tc=0x431f1b0, what_to_do=1 '\001') at src/gc/orchestrate.c:407
#4  0x00007f20094f3099 in MVM_gc_enter_from_interrupt (tc=0x431f1b0) at src/gc/orchestrate.c:611
#5  0x00007f20094f3441 in MVM_gc_allocate_nursery (tc=0x431f1b0, size=48) at src/gc/allocation.c:18
#6  0x00007f20094f3283 in MVM_gc_allocate (tc=0x431f1b0, size=48) at src/gc/allocation.h:13
#7  0x00007f20094f34f6 in MVM_gc_allocate_zeroed (tc=0x431f1b0, size=48) at src/gc/allocation.c:49
#8  0x00007f20094f36bd in MVM_gc_allocate_object (tc=0x431f1b0, st=0x196d670) at src/gc/allocation.c:86
#9  0x00007f200954d936 in attrref (tc=0x431f1b0, type=0x196f3c8, obj=0x457cfb0, class_handle=0x2756b58, name=0x25f2410) at src/6model/reprs/NativeRef.c:337
#10 0x00007f200954da27 in MVM_nativeref_attr_i (tc=0x431f1b0, obj=0x457cfb0, class_handle=0x2756b58, name=0x25f2410) at src/6model/reprs/NativeRef.c:348
#11 0x00007f20094ace08 in MVM_interp_run (tc=0x431f1b0, initial_invoke=0x7f20094c9261 <thread_initial_invoke>, invoke_data=0x3ebbb30) at src/core/interp.c:4594
#12 0x00007f20094c93aa in start_thread (data=0x3ebbb30) at src/core/threads.c:87
#13 0x00007f20089d56ba in start_thread (arg=0x7f200562c700) at pthread_create.c:333
#14 0x00007f2008ffb41d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
(gdb)