Panic when building the core setting with a small nursery

gistfile1.txt

dogbert@dogbert-VirtualBox ~/repos/rakudo $ gdb --args /home/dogbert/repos/rakudo/nqp/MoarVM/../../install/bin/moar --libpath="blib" --libpath="/home/dogbert/repos/rakudo/install/share/nqp/lib" --libpath="/home/dogbert/repos/rakudo/install/share/nqp/lib" perl6.moarvm --nqp-lib=blib --setting=NULL --ll-exception --optimize=3 --target=mbc --stagestats --output=CORE.setting.moarvm gen/moar/CORE.setting
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Reading symbols from /home/dogbert/repos/rakudo/nqp/MoarVM/../../install/bin/moar...done.
(gdb) b MVM_panic
Function "MVM_panic" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (MVM_panic) pending.
(gdb) r
Starting program: /home/dogbert/repos/rakudo/install/bin/moar --libpath=blib --libpath=/home/dogbert/repos/rakudo/install/share/nqp/lib --libpath=/home/dogbert/repos/rakudo/install/share/nqp/lib perl6.moarvm --nqp-lib=blib --setting=NULL --ll-exception --optimize=3 --target=mbc --stagestats --output=CORE.setting.moarvm gen/moar/CORE.setting
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[New Thread 0xb77d4b40 (LWP 23672)]
Stage start      :   0.000
Stage parse      : 
Breakpoint 1, MVM_panic (exitCode=1, messageFormat=0xb7cb7edc "Collectable %p in fromspace accessed") at src/core/exceptions.c:688
688	    fprintf(stderr, "MoarVM panic: ");
(gdb) bt
#0  MVM_panic (exitCode=1, messageFormat=0xb7cb7edc "Collectable %p in fromspace accessed") at src/core/exceptions.c:688
#1  0xb7be52a5 in push (tc=0x804c5b8, st=0x8078988, root=0xb6c917a4, data=0xb6c917b4, value=..., kind=8) at src/6model/reprs/VMArray.c:472
#2  0xb7bde6c9 in MVM_repr_push_o (tc=0x804c5b8, obj=0xb6c917a4, pushee=0xb7876f30) at src/6model/reprconv.c:342
#3  0xb7be285c in finish_parameterizing (tc=0x804c5b8, sr_data=0x23123d20) at src/6model/parametric.c:63
#4  0xb7b9b9c1 in remove_one_frame (tc=0x804c5b8, unwind=0 '\000') at src/core/frame.c:818
#5  0xb7b9bc99 in MVM_frame_try_return (tc=0x804c5b8) at src/core/frame.c:889
#6  0xb7b615cb in MVM_interp_run (tc=0x804c5b8, initial_invoke=0xb7c88032 <toplevel_initial_invoke>, invoke_data=0x80bb768) at src/core/interp.c:486
#7  0xb7c88191 in MVM_vm_run_file (instance=0x804c008, filename=0xbffff253 "perl6.moarvm") at src/moar.c:387
#8  0x08048f4f in main (argc=13, argv=0xbfffefa4) at src/main.c:255
(gdb) f 1
#1  0xb7be52a5 in push (tc=0x804c5b8, st=0x8078988, root=0xb6c917a4, data=0xb6c917b4, value=..., kind=8) at src/6model/reprs/VMArray.c:472
472	            MVM_ASSIGN_REF(tc, &(root->header), body->slots.o[body->start + body->elems - 1], value.o);
(gdb) p MVM_dump_backtrace(tc)
   at gen/moar/Metamodel.nqp:3806  (blib/Perl6/Metamodel.moarvm:new_type)
 from src/Perl6/World.nqp:3602  (blib/Perl6/World.moarvm:create_definite_type)
 from src/Perl6/World.nqp:3002  (blib/Perl6/World.moarvm:generate_accessor)
 from SETTING::src/core/Rakudo/Internals.pm:1257  (<ephemeral file>:generate_accessor)
 from SETTING::src/core/Attribute.pm:30  (<ephemeral file>:)
 from SETTING::src/core/Attribute.pm:29  (<ephemeral file>:)
 from SETTING::src/core/Attribute.pm:23  (<ephemeral file>:)
 from SETTING::src/core/Attribute.pm:20  (<ephemeral file>:compose)
 from gen/moar/Metamodel.nqp:397  (blib/Perl6/Metamodel.moarvm:compose_attributes)
 from gen/moar/Metamodel.nqp:3074  (blib/Perl6/Metamodel.moarvm:compose)
 from src/Perl6/World.nqp:2955  (blib/Perl6/World.moarvm:)
 from src/Perl6/World.nqp:4902  (blib/Perl6/World.moarvm:)
 from src/Perl6/World.nqp:4900  (blib/Perl6/World.moarvm:ex-handle)
 from src/Perl6/World.nqp:2955  (blib/Perl6/World.moarvm:pkg_compose)
 from gen/moar/Perl6-Actions.nqp:2988  (blib/Perl6/Actions.moarvm:package_def)
 from gen/moar/stage2/QRegex.nqp:1683  (/home/dogbert/repos/rakudo/install/share/nqp/lib/QRegex.moarvm:!reduce)
 from gen/moar/stage2/QRegex.nqp:1629  (/home/dogbert/repos/rakudo/install/share/nqp/lib/QRegex.moarvm:!cursor_pass)
 from src/Perl6/Grammar.nqp:2517  (blib/Perl6/Grammar.moarvm:package_def)
 from <unknown>:1  (blib/Perl6/Grammar.moarvm:package_declarator:sym<class>)
 from gen/moar/stage2/QRegex.nqp:1721  (/home/dogbert/repos/rakudo/install/share/nqp/lib/QRegex.moarvm:!protoregex)
 from <unknown>:1  (blib/Perl6/Grammar.moarvm:package_declarator)
 from src/Perl6/Grammar.nqp:2601  (blib/Perl6/Grammar.moarvm:scoped)
 from <unknown>:1  (blib/Perl6/Grammar.moarvm:scope_declarator:sym<my>)
 from gen/moar/stage2/QRegex.nqp:1721  (/home/dogbert/repos/rakudo/install/share/nqp/lib/QRegex.moarvm:!protoregex)
 from <unknown>:1  (blib/Perl6/Grammar.moarvm:scope_declarator)
 from <unknown>:1  (blib/Perl6/Grammar.moarvm:term:sym<scope_declarator>)
 from gen/moar/stage2/QRegex.nqp:1721  (/home/dogbert/repos/rakudo/install/share/nqp/lib/QRegex.moarvm:!protoregex)
 from <unknown>:1  (blib/Perl6/Grammar.moarvm:term)
 from src/Perl6/Grammar.nqp:3940  (blib/Perl6/Grammar.moarvm:termish)
 from gen/moar/stage2/NQPHLL.nqp:875  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:EXPR)
 from src/Perl6/Grammar.nqp:3980  (blib/Perl6/Grammar.moarvm:EXPR)
 from src/Perl6/Grammar.nqp:1305  (blib/Perl6/Grammar.moarvm:statement)
 from src/Perl6/Grammar.nqp:1237  (blib/Perl6/Grammar.moarvm:statementlist)
 from gen/moar/stage2/NQPHLL.nqp:1105  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:LANG)
 from src/Perl6/Grammar.nqp:1676  (blib/Perl6/Grammar.moarvm:FOREIGN_LANG)
 from src/Perl6/Grammar.nqp:1201  (blib/Perl6/Grammar.moarvm:comp_unit)
 from src/Perl6/Grammar.nqp:508  (blib/Perl6/Grammar.moarvm:TOP)
 from gen/moar/stage2/QRegex.nqp:2330  (/home/dogbert/repos/rakudo/install/share/nqp/lib/QRegex.moarvm:parse)
 from gen/moar/stage2/NQPHLL.nqp:1864  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:parse)
 from gen/moar/stage2/NQPHLL.nqp:1780  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:execute_stage)
 from gen/moar/stage2/NQPHLL.nqp:1813  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:run)
 from gen/moar/stage2/NQPHLL.nqp:1816  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:)
 from gen/moar/stage2/NQPHLL.nqp:1802  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:compile)
 from gen/moar/stage2/NQPHLL.nqp:1511  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:eval)
 from gen/moar/stage2/NQPHLL.nqp:1757  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:evalfiles)
 from gen/moar/stage2/NQPHLL.nqp:1649  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:command_eval)
 from src/Perl6/Compiler.nqp:42  (blib/Perl6/Compiler.moarvm:command_eval)
 from gen/moar/stage2/NQPHLL.nqp:1617  (/home/dogbert/repos/rakudo/install/share/nqp/lib/NQPHLL.moarvm:command_line)
 from gen/moar/main.nqp:47  (perl6.moarvm:MAIN)
 from gen/moar/main.nqp:38  (perl6.moarvm:<mainline>)
 from <unknown>:1  (perl6.moarvm:<main>)
 from <unknown>:1  (perl6.moarvm:<entry>)
$1 = void
(gdb)