SEGV when running example included in R#1951

gistfile1.txt

dogbert@dogbert-VirtualBox ~ $ gdb .rakudobrew/moar-master/install/bin/moar core
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Reading symbols from .rakudobrew/moar-master/install/bin/moar...done.
[New LWP 9374]
[New LWP 9373]
[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/.rakudobrew/moar-master/install/bin/moar --execname=/home/dogbert'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007fcad0a1c045 in MVM_multi_cache_find_spesh (tc=0x98eae0, cache_obj=0x3df8eb8, arg_info=0x7fcacf687450, type_tuple=0x7fcac810f560) at src/6model/reprs/MVMMultiCache.c:497
497	                known_type_st = type_tuple[tt_offset].decont_type->st;
[Current thread is 1 (Thread 0x7fcacf689700 (LWP 9374))]
(gdb) bt
#0  0x00007fcad0a1c045 in MVM_multi_cache_find_spesh (tc=0x98eae0, cache_obj=0x3df8eb8, arg_info=0x7fcacf687450, type_tuple=0x7fcac810f560) at src/6model/reprs/MVMMultiCache.c:497
#1  0x00007fcad0a6a00a in optimize_call (tc=0x98eae0, g=0x7fcac8180c20, bb=0x7fcac816b568, ins=0x7fcac816ad38, p=0x7fcac8103790, callee_idx=1, arg_info=0x7fcacf687450) at src/spesh/optimize.c:1857
#2  0x00007fcad0a6cbdd in optimize_bb_switch (tc=0x98eae0, g=0x7fcac8180c20, bb=0x7fcac816b568, p=0x7fcac8103790) at src/spesh/optimize.c:2670
#3  0x00007fcad0a6d3e1 in optimize_bb (tc=0x98eae0, g=0x7fcac8180c20, bb=0x7fcac816b568, p=0x7fcac8103790) at src/spesh/optimize.c:2918
#4  0x00007fcad0a6d444 in optimize_bb (tc=0x98eae0, g=0x7fcac8180c20, bb=0x7fcac816b508, p=0x7fcac8103790) at src/spesh/optimize.c:2930
#5  0x00007fcad0a6d444 in optimize_bb (tc=0x98eae0, g=0x7fcac8180c20, bb=0x7fcac816b448, p=0x7fcac8103790) at src/spesh/optimize.c:2930
#6  0x00007fcad0a6e7ca in MVM_spesh_optimize (tc=0x98eae0, g=0x7fcac8180c20, p=0x7fcac8103790) at src/spesh/optimize.c:3296
#7  0x00007fcad0a5a353 in MVM_spesh_candidate_add (tc=0x98eae0, p=0x7fcac8103790) at src/spesh/candidate.c:81
#8  0x00007fcad0a7737d in worker (tc=0x98eae0, callsite=0x7fcad1225540 <null_args_callsite>, args=0x0) at src/spesh/worker.c:16
#9  0x00007fcad09fd793 in invoke_handler (tc=0x98eae0, invokee=0x982170, callsite=0x7fcad1225540 <null_args_callsite>, args=0x0) at src/6model/reprs/MVMCFunction.c:9
#10 0x00007fcad09a37bc in thread_initial_invoke (tc=0x98eae0, data=0x98fe50) at src/core/threads.c:59
#11 0x00007fcad0962b65 in MVM_interp_run (tc=0x98eae0, initial_invoke=0x7fcad09a3731 <thread_initial_invoke>, invoke_data=0x98fe50) at src/core/interp.c:110
#12 0x00007fcad09a387a in start_thread (data=0x98fe50) at src/core/threads.c:87
#13 0x00007fcacfe9e6ba in start_thread (arg=0x7fcacf689700) at pthread_create.c:333
#14 0x00007fcad04c441d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
(gdb) info threads
  Id   Target Id         Frame 
* 1    Thread 0x7fcacf689700 (LWP 9374) 0x00007fcad0a1c045 in MVM_multi_cache_find_spesh (tc=0x98eae0, cache_obj=0x3df8eb8, arg_info=0x7fcacf687450, type_tuple=0x7fcac810f560)
    at src/6model/reprs/MVMMultiCache.c:497
  2    Thread 0x7fcad142f700 (LWP 9373) AO_nop_full () at 3rdparty/libatomicops/src/atomic_ops/sysdeps/gcc/generic.h:83