For Ruby "Bug #7629 Segmentation fault" (https://bugs.ruby-lang.org/issues/7629)

gdb.txt

$ gdb $HOME/.rbenv/versions/1.9.3-debug/bin/ruby /cores/core.65588
GNU gdb 6.3.50-20050815 (Apple version gdb-1822) (Sun Aug  5 03:00:42 UTC 2012)
Copyright 2004 Free Software Foundation, Inc.
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This GDB was configured as "x86_64-apple-darwin"...Reading symbols for shared libraries ... done

Reading symbols for shared libraries . done
Reading symbols for shared libraries .................................................................................. done
#0  0x00007fff85d65212 in __pthread_kill ()
(gdb) bt
#0  0x00007fff85d65212 in __pthread_kill ()
#1  0x00007fff8c31daf4 in pthread_kill ()
#2  0x00007fff8c361dce in abort ()
#3  0x000000010a23d6fa in rb_bug (fmt=0x10a41ae27 "Segmentation fault") at error.c:284
#4  0x000000010a344032 in sigsegv (sig=11, info=0x10a722ee0, ctx=0x10a722f48) at signal.c:609
#5  <signal handler called>
#6  0x000000010a3f3950 in rb_vm_make_env_object (th=0x7fe810404000, cfp=0x7fe81691c758) at vm.c:485
#7  0x000000010a3f3d25 in rb_vm_make_proc (th=0x7fe810404000, block=0x7fe81691c780, klass=140634686405440) at vm.c:562
#8  0x000000010a3f3c8e in vm_make_proc_from_block (th=0x7fe810404000, block=0x7fe81691c780) at vm.c:546
#9  0x000000010a3f399b in rb_vm_make_env_object (th=0x7fe810404000, cfp=0x10a6e17f0) at vm.c:488
#10 0x000000010a3f3d25 in rb_vm_make_proc (th=0x7fe810404000, block=0x10a6e1818, klass=140634686405440) at vm.c:562
#11 0x000000010a3f3c8e in vm_make_proc_from_block (th=0x7fe810404000, block=0x10a6e1818) at vm.c:546
#12 0x000000010a3f399b in rb_vm_make_env_object (th=0x7fe810404000, cfp=0x10a6e1798) at vm.c:488
#13 0x000000010a3f3d25 in rb_vm_make_proc (th=0x7fe810404000, block=0x10a6e17c0, klass=140634686405440) at vm.c:562
#14 0x000000010a3f3c8e in vm_make_proc_from_block (th=0x7fe810404000, block=0x10a6e17c0) at vm.c:546
#15 0x000000010a3f399b in rb_vm_make_env_object (th=0x7fe810404000, cfp=0x10a6e1740) at vm.c:488
#16 0x000000010a3f3d25 in rb_vm_make_proc (th=0x7fe810404000, block=0x10a6e1768, klass=140634686405440) at vm.c:562
#17 0x000000010a3d8ee2 in vm_callee_setup_arg_complex (th=0x7fe810404000, iseq=0x7fe812d77d30, orig_argc=2, orig_argv=0x10a5e3990, block=0x7fff55a03d58) at vm_insnhelper.c:221
#18 0x000000010a3e8419 in vm_setup_method (th=0x7fe810404000, cfp=0x10a6e1740, recv=140634702631280, argc=2, blockptr=0x10a6e1768, flag=0, me=0x7fe812ced650) at vm_insnhelper.c:470
#19 0x000000010a3e716e in vm_call_method (th=0x7fe810404000, cfp=0x10a6e1740, num=2, blockptr=0x10a6e1768, flag=0, id=84056, me=0x7fe812ced650, recv=140634702631280) at vm_insnhelper.c:529
#20 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#21 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#22 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x7fe816868e70, self=140634702631280, argc=1, argv=0x7fff55a05800, blockptr=0x0, cref=0x0) at vm.c:631
#23 0x000000010a3f43a4 in rb_vm_invoke_proc (th=0x7fe810404000, proc=0x7fe816868e70, self=140634702631280, argc=1, argv=0x7fff55a05800, blockptr=0x0) at vm.c:677
#24 0x000000010a3e8a9a in vm_call_bmethod (th=0x7fe810404000, recv=140634702631280, argc=1, argv=0x7fff55a05800, blockptr=0x0, me=0x7fe8169268f0) at vm_insnhelper.c:433
#25 0x000000010a3e764d in vm_call_method (th=0x7fe810404000, cfp=0x10a6e18a0, num=1, blockptr=0x0, flag=6, id=45944, me=0x7fe8169268f0, recv=140634702631280) at vm_insnhelper.c:566
#26 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#27 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#28 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x7fff55a07130, self=140634693368400, argc=1, argv=0x7fff55a07190, blockptr=0x0, cref=0x7fe81780c260) at vm.c:631
#29 0x000000010a3f3e3f in vm_yield_with_cref (th=0x7fe810404000, argc=1, argv=0x7fff55a07190, cref=0x7fe81780c260) at vm.c:654
#30 0x000000010a3f11c9 in yield_under (under=140634693367840, self=140634693368400, values=6) at vm_eval.c:1237
#31 0x000000010a3f1436 in specific_eval (argc=0, argv=0x10a5e3448, klass=140634693367840, self=140634693368400) at vm_eval.c:1267
#32 0x000000010a3f163c in rb_obj_instance_eval (argc=0, argv=0x10a5e3448, self=140634693368400) at vm_eval.c:1333
#33 0x000000010a3e8ea3 in call_cfunc (func=0x10a3f15c0 <rb_obj_instance_eval>, recv=140634693368400, len=-1, argc=0, argv=0x10a5e3448) at vm_insnhelper.c:317
#34 0x000000010a3e88e4 in vm_call_cfunc (th=0x7fe810404000, reg_cfp=0x10a6e23a0, num=0, recv=140634693368400, blockptr=0x7fe817017200, me=0x7fe810421770) at vm_insnhelper.c:404
#35 0x000000010a3e71d1 in vm_call_method (th=0x7fe810404000, cfp=0x10a6e23a0, num=0, blockptr=0x7fe817017200, flag=4, id=2904, me=0x7fe810421770, recv=140634693368400) at vm_insnhelper.c:534
#36 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#37 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#38 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x10a6e2580, self=140634693366200, argc=1, argv=0x7fff55a08ea8, blockptr=0x0, cref=0x0) at vm.c:631
#39 0x000000010a3f4290 in vm_yield (th=0x7fe810404000, argc=1, argv=0x7fff55a08ea8) at vm.c:661
#40 0x000000010a3ef51c in rb_yield_0 (argc=1, argv=0x7fff55a08ea8) at vm_eval.c:760
#41 0x000000010a3ef4d8 in rb_yield (val=140634728582000) at vm_eval.c:770
#42 0x000000010a1fc358 in rb_ary_each (array=140634693366200) at array.c:1495
#43 0x000000010a3e8ecb in call_cfunc (func=0x10a1fc290 <rb_ary_each>, recv=140634693366200, len=0, argc=0, argv=0x10a5e33c8) at vm_insnhelper.c:320
#44 0x000000010a3e88e4 in vm_call_cfunc (th=0x7fe810404000, reg_cfp=0x10a6e2558, num=0, recv=140634693366200, blockptr=0x10a6e2580, me=0x7fe810446eb0) at vm_insnhelper.c:404
#45 0x000000010a3e71d1 in vm_call_method (th=0x7fe810404000, cfp=0x10a6e2558, num=0, blockptr=0x10a6e2580, flag=8, id=424, me=0x7fe810446eb0, recv=140634693366200) at vm_insnhelper.c:534
#46 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#47 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#48 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x10a6e28f0, self=140634728559440, argc=1, argv=0x7fff55a0ab38, blockptr=0x0, cref=0x0) at vm.c:631
#49 0x000000010a3f4290 in vm_yield (th=0x7fe810404000, argc=1, argv=0x7fff55a0ab38) at vm.c:661
#50 0x000000010a3ef51c in rb_yield_0 (argc=1, argv=0x7fff55a0ab38) at vm_eval.c:760
#51 0x000000010a3ef4d8 in rb_yield (val=140634728577760) at vm_eval.c:770
#52 0x000000010a200624 in rb_ary_collect (ary=140634688449120) at array.c:2238
#53 0x000000010a3e8ecb in call_cfunc (func=0x10a200510 <rb_ary_collect>, recv=140634688449120, len=0, argc=0, argv=0x10a5e3280) at vm_insnhelper.c:320
#54 0x000000010a3e88e4 in vm_call_cfunc (th=0x7fe810404000, reg_cfp=0x10a6e28c8, num=0, recv=140634688449120, blockptr=0x10a6e28f0, me=0x7fe810447aa0) at vm_insnhelper.c:404
#55 0x000000010a3e71d1 in vm_call_method (th=0x7fe810404000, cfp=0x10a6e28c8, num=0, blockptr=0x10a6e28f0, flag=0, id=1568, me=0x7fe810447aa0, recv=140634688449120) at vm_insnhelper.c:534
#56 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#57 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#58 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x10a6e2aa8, self=140634730072040, argc=1, argv=0x7fff55a0c7c8, blockptr=0x0, cref=0x0) at vm.c:631
#59 0x000000010a3f4290 in vm_yield (th=0x7fe810404000, argc=1, argv=0x7fff55a0c7c8) at vm.c:661
#60 0x000000010a3ef51c in rb_yield_0 (argc=1, argv=0x7fff55a0c7c8) at vm_eval.c:760
#61 0x000000010a3ef4d8 in rb_yield (val=140634728559440) at vm_eval.c:770
#62 0x000000010a200624 in rb_ary_collect (ary=140634728576280) at array.c:2238
#63 0x000000010a3e8ecb in call_cfunc (func=0x10a200510 <rb_ary_collect>, recv=140634728576280, len=0, argc=0, argv=0x10a5e31e8) at vm_insnhelper.c:320
#64 0x000000010a3e88e4 in vm_call_cfunc (th=0x7fe810404000, reg_cfp=0x10a6e2a80, num=0, recv=140634728576280, blockptr=0x10a6e2aa8, me=0x7fe810447aa0) at vm_insnhelper.c:404
#65 0x000000010a3e71d1 in vm_call_method (th=0x7fe810404000, cfp=0x10a6e2a80, num=0, blockptr=0x10a6e2aa8, flag=0, id=1568, me=0x7fe810447aa0, recv=140634728576280) at vm_insnhelper.c:534
#66 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#67 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#68 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x10a6e2c08, self=140634761697520, argc=1, argv=0x7fff55a0e458, blockptr=0x0, cref=0x0) at vm.c:631
#69 0x000000010a3f4290 in vm_yield (th=0x7fe810404000, argc=1, argv=0x7fff55a0e458) at vm.c:661
#70 0x000000010a3ef51c in rb_yield_0 (argc=1, argv=0x7fff55a0e458) at vm_eval.c:760
#71 0x000000010a3ef4d8 in rb_yield (val=140634730072040) at vm_eval.c:770
#72 0x000000010a200624 in rb_ary_collect (ary=140634688358120) at array.c:2238
#73 0x000000010a3e8ecb in call_cfunc (func=0x10a200510 <rb_ary_collect>, recv=140634688358120, len=0, argc=0, argv=0x10a5e3170) at vm_insnhelper.c:320
#74 0x000000010a3e88e4 in vm_call_cfunc (th=0x7fe810404000, reg_cfp=0x10a6e2be0, num=0, recv=140634688358120, blockptr=0x10a6e2c08, me=0x7fe810447aa0) at vm_insnhelper.c:404
#75 0x000000010a3e71d1 in vm_call_method (th=0x7fe810404000, cfp=0x10a6e2be0, num=0, blockptr=0x10a6e2c08, flag=0, id=1568, me=0x7fe810447aa0, recv=140634688358120) at vm_insnhelper.c:534
#76 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#77 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#78 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x10a6e2d68, self=140634698876080, argc=1, argv=0x7fff55a100e8, blockptr=0x0, cref=0x0) at vm.c:631
#79 0x000000010a3f4290 in vm_yield (th=0x7fe810404000, argc=1, argv=0x7fff55a100e8) at vm.c:661
#80 0x000000010a3ef51c in rb_yield_0 (argc=1, argv=0x7fff55a100e8) at vm_eval.c:760
#81 0x000000010a3ef4d8 in rb_yield (val=140634761697520) at vm_eval.c:770
#82 0x000000010a200624 in rb_ary_collect (ary=140634698876000) at array.c:2238
#83 0x000000010a3e8ecb in call_cfunc (func=0x10a200510 <rb_ary_collect>, recv=140634698876000, len=0, argc=0, argv=0x10a5e30f8) at vm_insnhelper.c:320
#84 0x000000010a3e88e4 in vm_call_cfunc (th=0x7fe810404000, reg_cfp=0x10a6e2d40, num=0, recv=140634698876000, blockptr=0x10a6e2d68, me=0x7fe810447aa0) at vm_insnhelper.c:404
#85 0x000000010a3e71d1 in vm_call_method (th=0x7fe810404000, cfp=0x10a6e2d40, num=0, blockptr=0x10a6e2d68, flag=0, id=1568, me=0x7fe810447aa0, recv=140634698876000) at vm_insnhelper.c:534
#86 0x000000010a3df8a3 in vm_exec_core (th=0x7fe810404000, initial=0) at insns.def:1018
#87 0x000000010a3f5e8b in vm_exec (th=0x7fe810404000) at vm.c:1227
#88 0x000000010a3f41c2 in invoke_block_from_c (th=0x7fe810404000, block=0x7fe811ca0640, self=140634698798440, argc=0, argv=0x7fe8108c1500, blockptr=0x0, cref=0x0) at vm.c:631
#89 0x000000010a3f43a4 in rb_vm_invoke_proc (th=0x7fe810404000, proc=0x7fe811ca0640, self=140634698798440, argc=0, argv=0x7fe8108c1500, blockptr=0x0) at vm.c:677
#90 0x000000010a24ac61 in rb_proc_call (self=140634686756120, args=140634686756080) at proc.c:584
#91 0x000000010a243890 in rb_call_end_proc (data=140634686756120) at eval_jump.c:13
#92 0x000000010a243bd1 in rb_exec_end_proc () at eval_jump.c:126
#93 0x000000010a243ed5 in ruby_finalize_0 () at eval.c:92
#94 0x000000010a2440e5 in ruby_cleanup (ex=0) at eval.c:133
#95 0x000000010a24459f in ruby_run_node (n=0x7fe8109cdd80) at eval.c:244
#96 0x000000010a1ede12 in main (argc=4, argv=0x7fff55a12408) at main.c:38
(gdb) frame 6
#6  0x000000010a3f3950 in rb_vm_make_env_object (th=0x7fe810404000, cfp=0x7fe81691c758) at vm.c:485
485	    blockptr = GC_GUARDED_PTR_REF(lfp[0]);
(gdb) frame
#6  0x000000010a3f3950 in rb_vm_make_env_object (th=0x7fe810404000, cfp=0x7fe81691c758) at vm.c:485
485	    blockptr = GC_GUARDED_PTR_REF(lfp[0]);
(gdb) info frame
Stack level 6, frame at 0x7fff55a038f0:
 rip = 0x10a3f3950 in rb_vm_make_env_object (vm.c:485); saved rip 0x10a3f3d25
 called by frame at 0x7fff55a03950, caller of frame at 0x10a722ab8
 source language c.
 Arglist at 0x7fff55a038e8, args: th=0x7fe810404000, cfp=0x7fe81691c758
 Locals at 0x7fff55a038e8, Previous frame's sp is 0x7fff55a038f0
 Saved registers:
  rsi at 0x7fff55a038d0, rdi at 0x7fff55a038d8, rbp at 0x7fff55a038e0, rip at 0x7fff55a038e8
(gdb) p *cfp
$1 = {
  pc = 0x7fe8143bd040, 
  sp = 0x7fe816919e40, 
  bp = 0x7fe816919e40, 
  iseq = 0x7fe814865160, 
  flag = 0, 
  self = 432937446, 
  lfp = 0x87600e, 
  dfp = 0x7fe8126a4aa8, 
  block_iseq = 0x0, 
  proc = 0, 
  me = 0x7fe81681de70
}
(gdb) p *lfp
Cannot access memory at address 0x87600e
(gdb) p lfp[0]
Cannot access memory at address 0x87600e
(gdb)