moarvm: pointer being realloc'd was not allocated

backtrace.txt

=====WHEN IT FAILS IN CLEANUP======
moar(74468,0x7fff7b6d9000) malloc: *** error for object 0x1098dd400: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug

Breakpoint 1, 0x00007fff96c6bf42 in malloc_error_break () from /usr/lib/system/libsystem_malloc.dylib
(gdb) bt
#0  0x00007fff96c6bf42 in malloc_error_break () from /usr/lib/system/libsystem_malloc.dylib
#1  0x00007fff96c5d001 in free () from /usr/lib/system/libsystem_malloc.dylib
#2  0x0000000100051f6d in gc_free () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#3  0x000000010003c8c5 in MVM_gc_collect_free_gen2_unmarked ()
   from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#4  0x00000001000399a0 in MVM_gc_global_destruction () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#5  0x00000001000bd967 in MVM_vm_destroy_instance () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#6  0x00000001000016fc in main ()
=======WHEN IT FAIL AT RUNTIME======
moar(74473,0x7fff7b6d9000) malloc: *** error for object 0x1088e75a0: pointer being realloc'd was not allocated
*** set a breakpoint in malloc_error_break to debug

Breakpoint 1, 0x00007fff96c6bf42 in malloc_error_break () from /usr/lib/system/libsystem_malloc.dylib
(gdb) bt
#0  0x00007fff96c6bf42 in malloc_error_break () from /usr/lib/system/libsystem_malloc.dylib
#1  0x00007fff96c61f36 in realloc () from /usr/lib/system/libsystem_malloc.dylib
#2  0x0000000100052244 in set_size_internal () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#3  0x0000000100050f04 in push () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#4  0x0000000100011586 in MVM_interp_run () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#5  0x00000001000bd811 in MVM_vm_run_file () from /Users/llfourn/tmp/p6/rakudo/install/lib/libmoar.dylib
#6  0x00000001000016e5 in main ()