GC error in new-disp, nursery 8k and MVM_GC_DEBUG=1

gistfile1.txt

dogbert@dogbert-VirtualBox:~/repos/rakudo$ gdb --args ./rakudo-m -Ilib t/spec/S17-procasync/many-processes-no-close-stdin.t
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Reading symbols from ./rakudo-m...
(gdb) set follow-fork-mode child
(gdb) b main
Breakpoint 1 at 0x1100: file rakudo-m.c, line 9.
(gdb) r
Starting program: /home/dogbert/repos/rakudo/rakudo-m -Ilib t/spec/S17-procasync/many-processes-no-close-stdin.t

Breakpoint 1, main (argc=3, argv=0x7fffffffdf68) at rakudo-m.c:9
9	{
(gdb) b MVM_panic
Function "MVM_panic" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 2 (MVM_panic) pending.
(gdb) c
Continuing.
process 252177 is executing new program: /home/dogbert/repos/rakudo/install/bin/moar
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Breakpoint 1, main (argc=8, argv=0x7fffffffdd98) at src/main.c:145
145	{
(gdb) b MVM_panic
Note: breakpoint 2 also set at pc 0x7ffff78c9df0.
Breakpoint 3 at 0x7ffff78c9df0: file src/core/exceptions.c, line 854.
(gdb) c
Continuing.
[New Thread 0x7ffff7303700 (LWP 252181)]
1..1
[New Thread 0x7fffeffff700 (LWP 252182)]
[New Thread 0x7fffef7fe700 (LWP 252183)]
[New Thread 0x7fffeeffd700 (LWP 252184)]
[Attaching after Thread 0x7fffeeffd700 (LWP 252184) fork to child process 252185]
[New inferior 2 (process 252185)]
[Detaching after fork from parent process 252177]
[Inferior 1 (process 252177) detached]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
process 252185 is executing new program: /bin/dash
Error in re-setting breakpoint 1: Function "main" not defined.
[Attaching after process 252185 fork to child process 252186]
[New inferior 3 (process 252186)]
[Detaching after fork from parent process 252185]
[Inferior 2 (process 252185) detached]
process 252186 is executing new program: /home/dogbert/repos/rakudo/rakudo-m
process 252186 is executing new program: /home/dogbert/repos/rakudo/install/bin/moar
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff7303700 (LWP 252187)]
[Switching to Thread 0x7ffff7347440 (LWP 252186)]

Thread 3.1 "moar" hit Breakpoint 2, MVM_panic (exitCode=exitCode@entry=1, messageFormat=messageFormat@entry=0x7ffff7a54118 "Adding pointer %p to past fromspace to GC worklist") at src/core/exceptions.c:854
854	MVM_NO_RETURN void MVM_panic(MVMint32 exitCode, const char *messageFormat, ...) {
(gdb) bt
#0  MVM_panic (exitCode=exitCode@entry=1, messageFormat=messageFormat@entry=0x7ffff7a54118 "Adding pointer %p to past fromspace to GC worklist") at src/core/exceptions.c:854
#1  0x00007ffff798845b in mark_resumption_temps (tc=tc@entry=0x555555559ea0, temps=0x5555589cd910, worklist=worklist@entry=0x5555589deec0, snapshot=snapshot@entry=0x0, dp=<optimized out>, dp=<optimized out>)
    at src/disp/program.c:2785
#2  0x00007ffff798e87d in MVM_disp_program_mark_record_temps (tc=tc@entry=0x555555559ea0, dp=<optimized out>, temps=<optimized out>, worklist=worklist@entry=0x5555589deec0, snapshot=snapshot@entry=0x0)
    at src/disp/program.c:2811
#3  0x00007ffff78f7e36 in mark (tc=tc@entry=0x555555559ea0, from_record=<optimized out>, worklist=worklist@entry=0x5555589deec0, snapshot=snapshot@entry=0x0) at src/core/callstack.c:561
#4  0x00007ffff78f9529 in MVM_callstack_mark_current_thread (tc=tc@entry=0x555555559ea0, worklist=worklist@entry=0x5555589deec0, snapshot=snapshot@entry=0x0) at src/core/callstack.c:609
#5  0x00007ffff791ec80 in MVM_gc_root_add_tc_roots_to_worklist (tc=tc@entry=0x555555559ea0, worklist=worklist@entry=0x5555589deec0, snapshot=snapshot@entry=0x0) at src/gc/roots.c:173
#6  0x00007ffff79229e2 in MVM_gc_collect (tc=tc@entry=0x555555559ea0, what_to_do=what_to_do@entry=0 '\000', gen=<optimized out>) at src/gc/collect.c:121
#7  0x00007ffff791b6ba in run_gc (tc=tc@entry=0x555555559ea0, what_to_do=what_to_do@entry=0 '\000') at src/gc/orchestrate.c:443
#8  0x00007ffff791c71f in MVM_gc_enter_from_allocator (tc=tc@entry=0x555555559ea0) at src/gc/orchestrate.c:598
#9  0x00007ffff791ca41 in MVM_gc_allocate_nursery (tc=0x555555559ea0, size=32) at src/gc/allocation.c:37
#10 0x00007ffff791cd96 in MVM_gc_allocate_object (tc=0x555555559ea0, st=<optimized out>) at src/gc/allocation.c:93
#11 0x00007ffff78c9232 in MVM_args_slurpy_named (tc=0x555555559ea0, ctx=0x0) at src/core/args.c:1166
#12 0x00007ffff78e1c38 in MVM_interp_run (tc=0x1, initial_invoke=0x7ffff7a54118, invoke_data=0x7ffff7a54118, outer_runloop=0x3) at src/core/interp.c:1281
#13 0x00005555555557f0 in main (argc=7, argv=0x7fffffffddc8) at src/main.c:305
(gdb) f 1
#1  0x00007ffff798845b in mark_resumption_temps (tc=tc@entry=0x555555559ea0, temps=0x5555589cd910, worklist=worklist@entry=0x5555589deec0, snapshot=snapshot@entry=0x0, dp=<optimized out>, dp=<optimized out>)
    at src/disp/program.c:2785
2785	                        add_collectable(tc, worklist, snapshot, temps[init_values[j].index].o,
(gdb) l
2780	            MVMCallsite *cs = dp->resumptions[i].init_callsite;
2781	            for (MVMuint32 j = 0; j < cs->flag_count; j++) {
2782	                if (init_values[j].source == MVM_DISP_RESUME_INIT_TEMP) {
2783	                    MVMCallsiteFlags flag = cs->arg_flags[j] & MVM_CALLSITE_ARG_TYPE_MASK;
2784	                    if (flag == MVM_CALLSITE_ARG_OBJ || flag == MVM_CALLSITE_ARG_STR)
2785	                        add_collectable(tc, worklist, snapshot, temps[init_values[j].index].o,
2786	                                "Dispatch program temporary (resumption initialization)");
2787	                }
2788	            }
2789	        }
(gdb)