Some small fixes

  ruby/ruby#8


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@30974 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

  ruby#8


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@30974 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Script for stackbrew and updating, fix 1.9 onbuild FROM line

This function can be called from boot_defclass().
No assumption can be made about object internals.

(lldb) run
Process 2386 launched: './miniruby' (x86_64)
Process 2386 stopped
* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
    frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
   318  VALUE
   319  rb_class_path_cached(VALUE klass)
   320  {
-> 321      st_table *ivtbl = RCLASS_IV_TBL(klass);
   322      st_data_t n;
   323
   324      if (!ivtbl) return Qnil;
(lldb) bt
* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
  * frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
    frame #1: 0x000000010009cbd0 miniruby`rb_raw_obj_info(buff="0x0000000100fa5798 [2    ] T_CLASS", buff_size=256, obj=4311373720) + 1393 at gc.c:9341
    frame #2: 0x000000010009cf16 miniruby`obj_info(obj=4311373720) + 98 at gc.c:9423
    frame #3: 0x000000010008ca87 miniruby`newobj_init(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007cf280, obj=4311373720) + 338 at gc.c:1887
    frame #4: 0x000000010008cd51 miniruby`newobj_of(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1) + 171 at gc.c:1970
    frame #5: 0x000000010008ce1b miniruby`rb_wb_protected_newobj_of(klass=0, flags=66) + 54 at gc.c:1990
    frame #6: 0x0000000100027563 miniruby`class_alloc(flags=2, klass=0) + 46 at class.c:165
    frame #7: 0x000000010002761a miniruby`rb_class_boot(super=0) + 35 at class.c:203
    frame #8: 0x0000000100028612 miniruby`boot_defclass(name="BasicObject", super=0) + 28 at class.c:537
    frame #9: 0x000000010002868b miniruby`Init_class_hierarchy + 26 at class.c:548
    frame #10: 0x00000001000efe69 miniruby`InitVM_Object + 9 at object.c:3892
    frame #11: 0x00000001000f138e miniruby`Init_Object + 57 at object.c:4122
    frame #12: 0x00000001000a59bd miniruby`rb_call_inits + 29 at inits.c:23
    frame #13: 0x000000010007af30 miniruby`ruby_setup + 229 at eval.c:61
    frame #14: 0x000000010007af7e miniruby`ruby_init + 13 at eval.c:78
    frame #15: 0x0000000100000c58 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 88 at main.c:41
    frame #16: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61562 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from InitVM_Object().
No assumption can be made about object internals.

(lldb) run
Process 10675 launched: './miniruby' (x86_64)
Process 10675 stopped
* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
    frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
   9380                 const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
   9381                 snprintf(buff, buff_size, "%s (called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)", buff,
   9382                          rb_id2name(me->called_id),
-> 9383                          method_type_name(me->def->type),
   9384                          me->def->alias_count,
   9385                          obj_info(me->owner),
   9386                          obj_info(me->defined_class));
(lldb) p *me
(rb_method_entry_t) $0 = {
  flags = 24602
  defined_class = 4311488400
  def = 0x0000000000000000
  called_id = 3057
  owner = 4311488400
}
(lldb) bt
* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
  * frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
    frame #1: 0x00000001000b7cbf miniruby`obj_info(obj=4311487880) + 95 at gc.c:9423
    frame #2: 0x00000001000c16a8 miniruby`newobj_init(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1, objspace=0x00000001007ee280, obj=4311487880) + 424 at gc.c:1887
    frame #3: 0x00000001000b4529 miniruby`newobj_of(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1) + 217 at gc.c:1970
    frame #4: 0x00000001000b46ab miniruby`rb_imemo_new(type=imemo_ment, v1=0, v2=3057, v3=4311488400, v0=4311488400) + 75 at gc.c:2017
    frame #5: 0x00000001002773b4 miniruby`rb_method_entry_alloc(called_id=3057, owner=4311488400, defined_class=4311488400, def=0x0000000000000000) + 52 at vm_method.c:368
    frame #6: 0x0000000100277307 miniruby`rb_method_entry_create(called_id=3057, klass=4311488400, visi=METHOD_VISI_PRIVATE, def=0x0000000000000000) + 71 at vm_method.c:389
    frame #7: 0x00000001002784c7 miniruby`rb_method_entry_make(klass=4311488400, mid=3057, defined_class=4311488400, visi=METHOD_VISI_PRIVATE, type=VM_METHOD_TYPE_CFUNC, def=0x0000000000000000, original_id=3057, opts=0x00007fff5fbfd9e8) + 1207 at vm_method.c:594
    frame #8: 0x00000001002770f9 miniruby`rb_add_method(klass=4311488400, mid=3057, type=VM_METHOD_TYPE_CFUNC, opts=0x00007fff5fbfd9e8, visi=METHOD_VISI_PRIVATE) + 73 at vm_method.c:650
    frame #9: 0x000000010027708a miniruby`rb_add_method_cfunc(klass=4311488400, mid=3057, func=(miniruby`rb_obj_dummy at object.c:1125), argc=0, visi=METHOD_VISI_PRIVATE) + 138 at vm_method.c:137
    frame #10: 0x00000001000391e4 miniruby`rb_define_private_method(klass=4311488400, name="initialize", func=(miniruby`rb_obj_dummy at object.c:1125), argc=0) + 68 at class.c:1529
    frame #11: 0x000000010013f5bf miniruby`InitVM_Object + 47 at object.c:3905
    frame #12: 0x0000000100142ffd miniruby`Init_Object + 61 at object.c:4122
    frame #13: 0x00000001000d4edd miniruby`rb_call_inits + 29 at inits.c:23
    frame #14: 0x000000010009fe66 miniruby`ruby_setup + 198 at eval.c:61
    frame #15: 0x000000010009febd miniruby`ruby_init + 13 at eval.c:78
    frame #16: 0x0000000100000a4d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
    frame #17: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61563 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from Init_VM().
No assumption can be made about object internals.

(lldb) run
Process 15734 launched: './miniruby' (x86_64)
Process 15734 stopped
* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
    frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
   9270 static void
   9271 rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
   9272 {
-> 9273     if (iseq->body->location.label) {
   9274         VALUE path = rb_iseq_path(iseq);
   9275         snprintf(buff, buff_size, "%s %s@%s:%d", buff,
   9276                  RSTRING_PTR(iseq->body->location.label),
(lldb) p *iseq
(rb_iseq_t) $0 = {
  flags = 28698
  reserved1 = 0
  body = 0x0000000000000000
  aux = {
    compile_data = 0x0000000000000000
    loader = (obj = 0, index = 0)
    trace_events = 0
  }
}
(lldb) bt
* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
  * frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
    frame #1: 0x00000001000bde72 miniruby`rb_raw_obj_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, obj=4311097160) + 2786 at gc.c:9396
    frame #2: 0x00000001000b7c5f miniruby`obj_info(obj=4311097160) + 95 at gc.c:9428
    frame #3: 0x00000001000c16a8 miniruby`newobj_init(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007ee280, obj=4311097160) + 424 at gc.c:1887
    frame #4: 0x00000001000b44c9 miniruby`newobj_of(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1) + 217 at gc.c:1970
    frame #5: 0x00000001000b464b miniruby`rb_imemo_new(type=imemo_iseq, v1=0, v2=0, v3=0, v0=0) + 75 at gc.c:2017
    frame #6: 0x00000001000fd914 miniruby`iseq_imemo_alloc + 36 at iseq.h:156
    frame #7: 0x00000001000f6e1d miniruby`iseq_alloc + 13 at iseq.c:211
    frame #8: 0x00000001000f6bf8 miniruby`rb_iseq_new_with_opt(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, first_lineno=1, parent=0x0000000000000000, type=ISEQ_TYPE_TOP, option=0x0000000100335c30) + 56 at iseq.c:519
    frame #9: 0x00000001000f6bb6 miniruby`rb_iseq_new(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, parent=0x0000000000000000, type=ISEQ_TYPE_TOP) + 86 at iseq.c:480
    frame #10: 0x0000000100284bb0 miniruby`Init_VM + 1040 at vm.c:3022
    frame #11: 0x00000001000d4f7d miniruby`rb_call_inits + 189 at inits.c:55
    frame #12: 0x000000010009fe06 miniruby`ruby_setup + 198 at eval.c:61
    frame #13: 0x000000010009fe5d miniruby`ruby_init + 13 at eval.c:78
    frame #14: 0x00000001000009ed miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
    frame #15: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61564 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from rb_data_typed_object_zalloc().
No assumption can be made about object internals.

(lldb) run
Process 22135 launched: './miniruby' (x86_64)
Process 22135 stopped
* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
    frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
   1361         break;
   1362     }
   1363 #endif
-> 1364     return block->type;
   1365 }
   1366
   1367 static inline void
(lldb) bt
* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
  * frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
    frame #1: 0x000000010008acdb miniruby`vm_block_iseq(block=0x0000000000000000) + 24 at vm_core.h:1399
    frame #2: 0x000000010008acc1 miniruby`vm_proc_iseq(procval=4310866360) + 32 at vm_core.h:1387
    frame #3: 0x000000010009cbed miniruby`rb_raw_obj_info(buff="0x0000000100f299b8 [0    ] proc (Proc)", buff_size=256, obj=4310866360) + 1513 at gc.c:9349
    frame #4: 0x000000010009cf01 miniruby`obj_info(obj=4310866360) + 98 at gc.c:9428
    frame #5: 0x000000010008ca1b miniruby`newobj_init(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32, objspace=0x00000001007cf280, obj=4310866360) + 338 at gc.c:1887
    frame #6: 0x000000010008cce5 miniruby`newobj_of(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32) + 171 at gc.c:1970
    frame #7: 0x000000010008d01d miniruby`rb_data_typed_object_wrap(klass=4311027960, datap=0x0000000000000000, type=0x0000000100311d60) + 133 at gc.c:2062
    frame #8: 0x000000010008d04e miniruby`rb_data_typed_object_zalloc(klass=4311027960, size=40, type=0x0000000100311d60) + 42 at gc.c:2073
    frame #9: 0x000000010011b459 miniruby`rb_proc_alloc(klass=4311027960) + 36 at proc.c:113
    frame #10: 0x0000000100204d8e miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x00000001025003f8, block_type=block_type_iseq, is_from_method='\0', is_lambda='\x01') + 44 at vm.c:814
    frame #11: 0x00000001002050d8 miniruby`rb_vm_make_proc_lambda(ec=0x00000001007cf548, captured=0x00000001025003f8, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
    frame #12: 0x000000010011c0d2 miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
    frame #13: 0x000000010011c154 miniruby`rb_block_lambda + 27 at proc.c:808
    frame #14: 0x00000001001ee7e3 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000102400480) + 41 at vm_insnhelper.c:1729
    frame #15: 0x00000001001ef2c3 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 386 at vm_insnhelper.c:1918
    frame #16: 0x00000001001ef412 miniruby`vm_call_cfunc(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 149 at vm_insnhelper.c:1934
    frame #17: 0x00000001001f0655 miniruby`vm_call_method_each_type(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 239 at vm_insnhelper.c:2232
    frame #18: 0x00000001001f0ce0 miniruby`vm_call_method(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 117 at vm_insnhelper.c:2355
    frame #19: 0x00000001001f0eb6 miniruby`vm_call_general(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 59 at vm_insnhelper.c:2398
    frame #20: 0x00000001001f6e61 miniruby`vm_exec_core(ec=0x00000001007cf548, initial=0) + 7480 at insns.def:850
    frame #21: 0x0000000100207995 miniruby`vm_exec(ec=0x00000001007cf548) + 230 at vm.c:1771
    frame #22: 0x0000000100208647 miniruby`rb_iseq_eval_main(iseq=0x0000000100f29fd0) + 52 at vm.c:2019
    frame #23: 0x000000010007b750 miniruby`ruby_exec_internal(n=0x0000000100f29fd0) + 297 at eval.c:246
    frame #24: 0x000000010007b876 miniruby`ruby_exec_node(n=0x0000000100f29fd0) + 36 at eval.c:310
    frame #25: 0x000000010007b849 miniruby`ruby_run_node(n=0x0000000100f29fd0) + 62 at eval.c:302
    frame #26: 0x0000000100000c05 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
    frame #27: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61565 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This imemo_name is used uninitialized because the switch
above does not cover all possible imemo types.

(lldb) run
Process 26068 launched: './miniruby' (x86_64)
Process 26068 stopped
* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
    frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
libsystem_c.dylib`strlen:
->  0x7fff8a402132 <+18>: pcmpeqb (%rdi), %xmm0
    0x7fff8a402136 <+22>: pmovmskb %xmm0, %esi
    0x7fff8a40213a <+26>: andq   $0xf, %rcx
    0x7fff8a40213e <+30>: orq    $-0x1, %rax
(lldb) bt
* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
  * frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
    frame #1: 0x00000001001f1531 miniruby`BSD_vfprintf(fp=0x00007fff5fbfc9e0, fmt0="%s %s", ap=0x00007fff5fbfcbf0) + 5873 at vsnprintf.c:1026
    frame #2: 0x00000001001ef213 miniruby`ruby_do_vsnprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s", ap=0x00007fff5fbfcbf0) + 131 at sprintf.c:1285
    frame #3: 0x00000001001ef3ea miniruby`ruby_snprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s") + 426 at sprintf.c:1300
    frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
    frame #5: 0x00000001000b7bff miniruby`obj_info(obj=4310983760) + 95 at gc.c:9428
    frame #6: 0x00000001000c1658 miniruby`newobj_init(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1, objspace=0x00000001007ee280, obj=4310983760) + 424 at gc.c:1887
    frame #7: 0x00000001000b4469 miniruby`newobj_of(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1) + 217 at gc.c:1970
    frame #8: 0x00000001000b45eb miniruby`rb_imemo_new(type=imemo_ast, v1=0, v2=4303040512, v3=4310983800, v0=0) + 75 at gc.c:2017
    frame #9: 0x000000010011daed miniruby`rb_ast_new + 61 at node.c:1146
    frame #10: 0x0000000100160e15 miniruby`rb_parser_compile_file_path(vparser=4310984400, fname=4310984960, file=4310984080, start=1) + 53 at parse.y:5776
    frame #11: 0x00000001001e18ea miniruby`load_file_internal(argp_v=140734799795024) + 1834 at ruby.c:1907
    frame #12: 0x00000001000a1bb5 miniruby`rb_ensure(b_proc=(miniruby`load_file_internal at ruby.c:1795), data1=140734799795024, e_proc=(miniruby`restore_load_file at ruby.c:2007), data2=140734799795024) + 245 at eval.c:1037
    frame #13: 0x00000001001df4a4 miniruby`load_file(parser=4310984400, fname=4310984960, f=4310984080, script=1, opt=0x00007fff5fbfda28) + 100 at ruby.c:2026
    frame #14: 0x00000001001e084e miniruby`process_options(argc=0, argv=0x00007fff5fbfdc00, opt=0x00007fff5fbfda28) + 3454 at ruby.c:1682
    frame #15: 0x00000001001dfaae miniruby`ruby_process_options(argc=2, argv=0x00007fff5fbfdbf0) + 238 at ruby.c:2257
    frame #16: 0x000000010009ff43 miniruby`ruby_options(argc=2, argv=0x00007fff5fbfdbf0) + 211 at eval.c:105
    frame #17: 0x0000000100000989 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 105 at main.c:42
    frame #18: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb) up 4
frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
   9373 #undef IMEMO_NAME
   9374               default: UNREACHABLE;
   9375             }
-> 9376             snprintf(buff, buff_size, "%s %s", buff, imemo_name);
   9377
   9378             switch (imemo_type(obj)) {
   9379               case imemo_ment: {
(lldb) p imemo_name
(const char *) $0 = 0xffffffffffffffff
(lldb) p imemo_type(obj)
(imemo_type) $1 = imemo_ast
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61566 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

obj_info() assumes the given object is alive.  Passing freed
objects to it results in SEGV.

(lldb) run
Process 29718 launched: './miniruby' (x86_64)
Process 29718 stopped
* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
    frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
   266      }
   267      else {
   268          VM_ASSERT(RB_TYPE_P(pathobj, T_ARRAY));
-> 269          return RARRAY_AREF(pathobj, PATHOBJ_PATH);
   270      }
   271  }
   272
(lldb) bt
* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
  * frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
    frame #1: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x000000010af34a20) + 32 at iseq.c:723
    frame #2: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, iseq=0x000000010af34a20) + 69 at gc.c:9274
    frame #3: 0x000000010009e45a miniruby`rb_raw_obj_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, obj=4478683680) + 2191 at gc.c:9397
    frame #4: 0x000000010009e4d5 miniruby`obj_info(obj=4478683680) + 98 at gc.c:9429
    frame #5: 0x0000000100091ae3 miniruby`gc_page_sweep(objspace=0x00000001007d3280, heap=0x00000001007d32a0, sweep_page=0x000000010ae07bc0) + 622 at gc.c:3529
    frame #6: 0x000000010009206a miniruby`gc_sweep_step(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 188 at gc.c:3705
    frame #7: 0x0000000100092254 miniruby`gc_sweep_continue(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 133 at gc.c:3772
    frame #8: 0x000000010008d7f9 miniruby`heap_prepare(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 48 at gc.c:1746
    frame #9: 0x000000010008d8a1 miniruby`heap_get_freeobj_from_next_freepage(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 37 at gc.c:1769
    frame #10: 0x000000010008d98d miniruby`heap_get_freeobj(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 83 at gc.c:1803
    frame #11: 0x000000010008dcb0 miniruby`newobj_slowpath(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280, wb_protected=1) + 220 at gc.c:1930
    frame #12: 0x000000010008dd6c miniruby`newobj_slowpath_wb_protected(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280) + 76 at gc.c:1942
    frame #13: 0x000000010008dea1 miniruby`newobj_of(klass=4334386280, flags=5, v1=0, v2=0, v3=0, wb_protected=1) + 221 at gc.c:1974
    frame #14: 0x000000010008df39 miniruby`rb_wb_protected_newobj_of(klass=4334386280, flags=5) + 54 at gc.c:1990
    frame #15: 0x0000000100195f7c miniruby`str_alloc(klass=4334386280) + 29 at string.c:692
    frame #16: 0x0000000100195fe9 miniruby`str_new0(klass=4334386280, ptr="gitm", len=4, termlen=1) + 73 at string.c:714
    frame #17: 0x000000010019633e miniruby`rb_enc_str_new(ptr="gitm", len=4, enc=0x00000001025d50a0) + 81 at string.c:766
    frame #18: 0x000000010010a80a miniruby`parser_str_new(p="gitm", n=4, enc=0x00000001025d50a0, func=66, enc0=0x00000001025d50a0) + 50 at parse.y:5817
    frame #19: 0x000000010010ce1a miniruby`parser_parse_string(parser=0x00000001042ac5c0, quote=0x000000010460c028) + 795 at parse.y:6675
    frame #20: 0x00000001001120bd miniruby`parser_yylex(parser=0x00000001042ac5c0) + 159 at parse.y:8281
    frame #21: 0x0000000100115068 miniruby`yylex(lval=0x00007fff5fbf9948, yylloc=0x00007fff5fbf9ab0, parser=0x00000001042ac5c0) + 55 at parse.y:8931
    frame #22: 0x00000001000fc79f miniruby`ruby_yyparse(parser=0x00000001042ac5c0) + 1198 at parse.c:5798
    frame #23: 0x0000000100109f5a miniruby`yycompile0(arg=4364879296) + 317 at parse.y:5595
    frame #24: 0x0000000100214ef0 miniruby`rb_suppress_tracing(func=(miniruby`yycompile0 at parse.y:5565), arg=4364879296) + 349 at vm_trace.c:397
    frame #25: 0x000000010010a1df miniruby`yycompile(parser=0x00000001042ac5c0, fname=4443743440, line=1) + 126 at parse.y:5637
    frame #26: 0x000000010010a4c1 miniruby`parser_compile_string(vparser=4443743480, fname=4443743440, s=4443743520, line=1) + 191 at parse.y:5706
    frame #27: 0x000000010010a5b7 miniruby`rb_parser_compile_string_path(vparser=4443743480, f=4443743440, s=4443743520, line=1) + 58 at parse.y:5730
    frame #28: 0x0000000100206025 miniruby`eval_make_iseq(src=4443743520, fname=4443743440, line=1, bind=0x0000000000000000, base_block=0x00007fff5fbfb370) + 266 at vm_eval.c:1274
    frame #29: 0x0000000100206153 miniruby`eval_string_with_cref(self=4334412520, src=4443743520, cref=0x0000000000000000, file=52, line=1) + 197 at vm_eval.c:1307
    frame #30: 0x0000000100206389 miniruby`rb_f_eval(argc=1, argv=0x0000000102400eb8, self=4334412520) + 219 at vm_eval.c:1382
    frame #31: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_eval at vm_eval.c:1364), recv=4334412520, argc=1, argv=0x0000000102400eb8) + 47 at vm_insnhelper.c:1723
    frame #32: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 386 at vm_insnhelper.c:1918
    frame #33: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 149 at vm_insnhelper.c:1934
    frame #34: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
    frame #35: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #36: 0x00000001002093f8 miniruby`invoke_block(ec=0x00000001007d3548, iseq=0x000000010252d7f0, self=4334412520, captured=0x0000000102500df8, cref=0x0000000000000000, type=572653569, opt_pc=0) + 224 at vm.c:988
    frame #37: 0x0000000100209766 miniruby`invoke_iseq_block_from_c(ec=0x00000001007d3548, captured=0x0000000102500df8, self=4334412520, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0) + 389 at vm.c:1040
    frame #38: 0x0000000100209824 miniruby`invoke_block_from_c_bh(ec=0x00000001007d3548, block_handler=4333768185, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0, force_blockarg=0) + 138 at vm.c:1058
    frame #39: 0x00000001002099d0 miniruby`vm_yield(ec=0x00000001007d3548, argc=0, argv=0x0000000000000000) + 69 at vm.c:1103
    frame #40: 0x0000000100205623 miniruby`rb_yield_0(argc=0, argv=0x0000000000000000) + 40 at vm_eval.c:970
    frame #41: 0x0000000100205964 miniruby`loop_i + 19 at vm_eval.c:1049
    frame #42: 0x000000010007db07 miniruby`rb_rescue2(b_proc=(miniruby`loop_i at vm_eval.c:1047), data1=0, r_proc=(miniruby`loop_stop at vm_eval.c:1056), data2=0) + 369 at eval.c:896
    frame #43: 0x0000000100205a2e miniruby`rb_f_loop(self=4334412520) + 121 at vm_eval.c:1100
    frame #44: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_f_loop at vm_eval.c:1098), recv=4334412520, argc=0, argv=0x0000000102400e80) + 41 at vm_insnhelper.c:1729
    frame #45: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 386 at vm_insnhelper.c:1918
    frame #46: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 149 at vm_insnhelper.c:1934
    frame #47: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 239 at vm_insnhelper.c:2232
    frame #48: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 253 at vm_insnhelper.c:2366
    frame #49: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 59 at vm_insnhelper.c:2398
    frame #50: 0x00000001001fab2f miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 7480 at insns.def:850
    frame #51: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #52: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x000000010252dd90) + 52 at vm.c:2019
    frame #53: 0x000000010007c768 miniruby`ruby_exec_internal(n=0x000000010252dd90) + 297 at eval.c:246
    frame #54: 0x000000010007c88e miniruby`ruby_exec_node(n=0x000000010252dd90) + 36 at eval.c:310
    frame #55: 0x000000010007c861 miniruby`ruby_run_node(n=0x000000010252dd90) + 62 at eval.c:302
    frame #56: 0x000000010000138d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
    frame #57: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb) p ((struct RVALUE*)pathobj)->as.basic
(RBasic) $0 = (flags = 0, klass = 4478683600)
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61568 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

obj_info() assumes the given object is alive.  OTOH
gc_writebarrier_incremental is called before or in middle of
object initialization.  Can casue SEGV.

(lldb) run
Process 48188 launched: './miniruby' (x86_64)
Process 48188 stopped
* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
    frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
   2069 static inline const VALUE *
   2070 rb_array_const_ptr(VALUE a)
   2071 {
-> 2072     return FIX_CONST_VALUE_PTR((RBASIC(a)->flags & RARRAY_EMBED_FLAG) ?
   2073         RARRAY(a)->as.ary : RARRAY(a)->as.heap.ptr);
   2074 }
   2075
(lldb) bt
* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
  * frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
    frame #1: 0x00000001000bfaab miniruby`pathobj_path(pathobj=5251291222225483145) + 70 at vm_core.h:269
    frame #2: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x00000001025b71a8) + 32 at iseq.c:723
    frame #3: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, iseq=0x00000001025b71a8) + 69 at gc.c:9274
    frame #4: 0x000000010009e1d5 miniruby`rb_raw_obj_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, obj=4334514520) + 1546 at gc.c:9351
    frame #5: 0x000000010009e4d5 miniruby`obj_info(obj=4334514520) + 98 at gc.c:9429
    frame #6: 0x0000000100096658 miniruby`gc_writebarrier_incremental(a=4334514520, b=4334514600, objspace=0x00000001007d3280) + 61 at gc.c:5963
    frame #7: 0x00000001000968ca miniruby`rb_gc_writebarrier(a=4334514520, b=4334514600) + 127 at gc.c:6009
    frame #8: 0x00000001001eabe0 miniruby`rb_obj_written(a=4334514520, oldv=52, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 72 at ruby.h:1472
    frame #9: 0x00000001001eac2c miniruby`rb_obj_write(a=4334514520, slot=0x000000010259ff10, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 70 at ruby.h:1489
    frame #10: 0x0000000100208b6f miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x0000000102500338, block_type=block_type_ifunc, is_from_method='\0', is_lambda='\x01') + 137 at vm.c:821
    frame #11: 0x0000000100208e5c miniruby`rb_vm_make_proc_lambda(ec=0x00000001007d3548, captured=0x0000000102500338, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
    frame #12: 0x000000010011f08e miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
    frame #13: 0x000000010011f110 miniruby`rb_block_lambda + 27 at proc.c:808
    frame #14: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000000000000) + 41 at vm_insnhelper.c:1729
    frame #15: 0x00000001002033de miniruby`vm_call0_cfunc_with_frame(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 370 at vm_eval.c:85
    frame #16: 0x00000001002034d9 miniruby`vm_call0_cfunc(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 59 at vm_eval.c:100
    frame #17: 0x000000010020368f miniruby`vm_call0_body(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 436 at vm_eval.c:131
    frame #18: 0x000000010020326a miniruby`vm_call0(ec=0x00000001007d3548, recv=4310991600, id=2993, argc=0, argv=0x0000000000000000, me=0x0000000100f48110) + 142 at vm_eval.c:58
    frame #19: 0x0000000100203c60 miniruby`rb_call0(ec=0x00000001007d3548, recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL, self=4334514640) + 166 at vm_eval.c:296
    frame #20: 0x0000000100204827 miniruby`rb_call(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL) + 84 at vm_eval.c:589
    frame #21: 0x000000010020518b miniruby`rb_funcallv(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000) + 52 at vm_eval.c:815
    frame #22: 0x000000010012242e miniruby`mlambda(method=0) + 45 at proc.c:2661
    frame #23: 0x0000000100205bac miniruby`rb_iterate0(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, ifunc=0x00000001025b71a8, ec=0x00000001007d3548) + 380 at vm_eval.c:1134
    frame #24: 0x0000000100205d16 miniruby`rb_iterate(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, bl_proc=(miniruby`bmcall at proc.c:2666), data2=4334514640) + 88 at vm_eval.c:1166
    frame #25: 0x00000001001224c7 miniruby`method_to_proc(method=4334514640) + 43 at proc.c:2701
    frame #26: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`method_to_proc at proc.c:2688), recv=4334514640, argc=0, argv=0x0000000102400568) + 41 at vm_insnhelper.c:1729
    frame #27: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 386 at vm_insnhelper.c:1918
    frame #28: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 149 at vm_insnhelper.c:1934
    frame #29: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 239 at vm_insnhelper.c:2232
    frame #30: 0x00000001001f49a4 miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 117 at vm_insnhelper.c:2355
    frame #31: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 59 at vm_insnhelper.c:2398
    frame #32: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
    frame #33: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #34: 0x000000010020c3d1 miniruby`rb_iseq_eval(iseq=0x00000001007f8270) + 52 at vm.c:2008
    frame #35: 0x00000001000caa4a miniruby`rb_load_internal0(ec=0x00000001007d3548, fname=4310799960, wrap=0) + 631 at load.c:611
    frame #36: 0x00000001000cab36 miniruby`rb_load_internal(fname=4310799960, wrap=0) + 46 at load.c:642
    frame #37: 0x00000001000cae1d miniruby`rb_f_load(argc=1, argv=0x00000001024004b8) + 217 at load.c:710
    frame #38: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_load at load.c:695), recv=4311327440, argc=1, argv=0x00000001024004b8) + 47 at vm_insnhelper.c:1723
    frame #39: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 386 at vm_insnhelper.c:1918
    frame #40: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 149 at vm_insnhelper.c:1934
    frame #41: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 239 at vm_insnhelper.c:2232
    frame #42: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 253 at vm_insnhelper.c:2366
    frame #43: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 59 at vm_insnhelper.c:2398
    frame #44: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
    frame #45: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #46: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x0000000100f21240) + 52 at vm.c:2019
    frame #47: 0x000000010007c774 miniruby`ruby_exec_internal(n=0x0000000100f21240) + 297 at eval.c:246
    frame #48: 0x000000010007c89a miniruby`ruby_exec_node(n=0x0000000100f21240) + 36 at eval.c:310
    frame #49: 0x000000010007c86d miniruby`ruby_run_node(n=0x0000000100f21240) + 62 at eval.c:302
    frame #50: 0x0000000100001399 miniruby`main(argc=9, argv=0x00007fff5fbfdae0) + 113 at main.c:42
    frame #51: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61569 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from boot_defclass().
No assumption can be made about object internals.

(lldb) run
Process 2386 launched: './miniruby' (x86_64)
Process 2386 stopped
* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
    frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
   318  VALUE
   319  rb_class_path_cached(VALUE klass)
   320  {
-> 321      st_table *ivtbl = RCLASS_IV_TBL(klass);
   322      st_data_t n;
   323
   324      if (!ivtbl) return Qnil;
(lldb) bt
* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
  * frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
    frame #1: 0x000000010009cbd0 miniruby`rb_raw_obj_info(buff="0x0000000100fa5798 [2    ] T_CLASS", buff_size=256, obj=4311373720) + 1393 at gc.c:9341
    frame #2: 0x000000010009cf16 miniruby`obj_info(obj=4311373720) + 98 at gc.c:9423
    frame #3: 0x000000010008ca87 miniruby`newobj_init(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007cf280, obj=4311373720) + 338 at gc.c:1887
    frame #4: 0x000000010008cd51 miniruby`newobj_of(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1) + 171 at gc.c:1970
    frame #5: 0x000000010008ce1b miniruby`rb_wb_protected_newobj_of(klass=0, flags=66) + 54 at gc.c:1990
    frame #6: 0x0000000100027563 miniruby`class_alloc(flags=2, klass=0) + 46 at class.c:165
    frame #7: 0x000000010002761a miniruby`rb_class_boot(super=0) + 35 at class.c:203
    frame #8: 0x0000000100028612 miniruby`boot_defclass(name="BasicObject", super=0) + 28 at class.c:537
    frame #9: 0x000000010002868b miniruby`Init_class_hierarchy + 26 at class.c:548
    frame #10: 0x00000001000efe69 miniruby`InitVM_Object + 9 at object.c:3892
    frame #11: 0x00000001000f138e miniruby`Init_Object + 57 at object.c:4122
    frame #12: 0x00000001000a59bd miniruby`rb_call_inits + 29 at inits.c:23
    frame #13: 0x000000010007af30 miniruby`ruby_setup + 229 at eval.c:61
    frame #14: 0x000000010007af7e miniruby`ruby_init + 13 at eval.c:78
    frame #15: 0x0000000100000c58 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 88 at main.c:41
    frame #16: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61562 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from InitVM_Object().
No assumption can be made about object internals.

(lldb) run
Process 10675 launched: './miniruby' (x86_64)
Process 10675 stopped
* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
    frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
   9380                 const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
   9381                 snprintf(buff, buff_size, "%s (called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)", buff,
   9382                          rb_id2name(me->called_id),
-> 9383                          method_type_name(me->def->type),
   9384                          me->def->alias_count,
   9385                          obj_info(me->owner),
   9386                          obj_info(me->defined_class));
(lldb) p *me
(rb_method_entry_t) $0 = {
  flags = 24602
  defined_class = 4311488400
  def = 0x0000000000000000
  called_id = 3057
  owner = 4311488400
}
(lldb) bt
* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
  * frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
    frame #1: 0x00000001000b7cbf miniruby`obj_info(obj=4311487880) + 95 at gc.c:9423
    frame #2: 0x00000001000c16a8 miniruby`newobj_init(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1, objspace=0x00000001007ee280, obj=4311487880) + 424 at gc.c:1887
    frame #3: 0x00000001000b4529 miniruby`newobj_of(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1) + 217 at gc.c:1970
    frame #4: 0x00000001000b46ab miniruby`rb_imemo_new(type=imemo_ment, v1=0, v2=3057, v3=4311488400, v0=4311488400) + 75 at gc.c:2017
    frame #5: 0x00000001002773b4 miniruby`rb_method_entry_alloc(called_id=3057, owner=4311488400, defined_class=4311488400, def=0x0000000000000000) + 52 at vm_method.c:368
    frame #6: 0x0000000100277307 miniruby`rb_method_entry_create(called_id=3057, klass=4311488400, visi=METHOD_VISI_PRIVATE, def=0x0000000000000000) + 71 at vm_method.c:389
    frame #7: 0x00000001002784c7 miniruby`rb_method_entry_make(klass=4311488400, mid=3057, defined_class=4311488400, visi=METHOD_VISI_PRIVATE, type=VM_METHOD_TYPE_CFUNC, def=0x0000000000000000, original_id=3057, opts=0x00007fff5fbfd9e8) + 1207 at vm_method.c:594
    frame #8: 0x00000001002770f9 miniruby`rb_add_method(klass=4311488400, mid=3057, type=VM_METHOD_TYPE_CFUNC, opts=0x00007fff5fbfd9e8, visi=METHOD_VISI_PRIVATE) + 73 at vm_method.c:650
    frame #9: 0x000000010027708a miniruby`rb_add_method_cfunc(klass=4311488400, mid=3057, func=(miniruby`rb_obj_dummy at object.c:1125), argc=0, visi=METHOD_VISI_PRIVATE) + 138 at vm_method.c:137
    frame #10: 0x00000001000391e4 miniruby`rb_define_private_method(klass=4311488400, name="initialize", func=(miniruby`rb_obj_dummy at object.c:1125), argc=0) + 68 at class.c:1529
    frame #11: 0x000000010013f5bf miniruby`InitVM_Object + 47 at object.c:3905
    frame #12: 0x0000000100142ffd miniruby`Init_Object + 61 at object.c:4122
    frame #13: 0x00000001000d4edd miniruby`rb_call_inits + 29 at inits.c:23
    frame #14: 0x000000010009fe66 miniruby`ruby_setup + 198 at eval.c:61
    frame #15: 0x000000010009febd miniruby`ruby_init + 13 at eval.c:78
    frame #16: 0x0000000100000a4d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
    frame #17: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61563 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from Init_VM().
No assumption can be made about object internals.

(lldb) run
Process 15734 launched: './miniruby' (x86_64)
Process 15734 stopped
* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
    frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
   9270 static void
   9271 rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
   9272 {
-> 9273     if (iseq->body->location.label) {
   9274         VALUE path = rb_iseq_path(iseq);
   9275         snprintf(buff, buff_size, "%s %s@%s:%d", buff,
   9276                  RSTRING_PTR(iseq->body->location.label),
(lldb) p *iseq
(rb_iseq_t) $0 = {
  flags = 28698
  reserved1 = 0
  body = 0x0000000000000000
  aux = {
    compile_data = 0x0000000000000000
    loader = (obj = 0, index = 0)
    trace_events = 0
  }
}
(lldb) bt
* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
  * frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
    frame #1: 0x00000001000bde72 miniruby`rb_raw_obj_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, obj=4311097160) + 2786 at gc.c:9396
    frame #2: 0x00000001000b7c5f miniruby`obj_info(obj=4311097160) + 95 at gc.c:9428
    frame #3: 0x00000001000c16a8 miniruby`newobj_init(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007ee280, obj=4311097160) + 424 at gc.c:1887
    frame #4: 0x00000001000b44c9 miniruby`newobj_of(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1) + 217 at gc.c:1970
    frame #5: 0x00000001000b464b miniruby`rb_imemo_new(type=imemo_iseq, v1=0, v2=0, v3=0, v0=0) + 75 at gc.c:2017
    frame #6: 0x00000001000fd914 miniruby`iseq_imemo_alloc + 36 at iseq.h:156
    frame #7: 0x00000001000f6e1d miniruby`iseq_alloc + 13 at iseq.c:211
    frame #8: 0x00000001000f6bf8 miniruby`rb_iseq_new_with_opt(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, first_lineno=1, parent=0x0000000000000000, type=ISEQ_TYPE_TOP, option=0x0000000100335c30) + 56 at iseq.c:519
    frame #9: 0x00000001000f6bb6 miniruby`rb_iseq_new(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, parent=0x0000000000000000, type=ISEQ_TYPE_TOP) + 86 at iseq.c:480
    frame #10: 0x0000000100284bb0 miniruby`Init_VM + 1040 at vm.c:3022
    frame #11: 0x00000001000d4f7d miniruby`rb_call_inits + 189 at inits.c:55
    frame #12: 0x000000010009fe06 miniruby`ruby_setup + 198 at eval.c:61
    frame #13: 0x000000010009fe5d miniruby`ruby_init + 13 at eval.c:78
    frame #14: 0x00000001000009ed miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
    frame #15: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61564 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This function can be called from rb_data_typed_object_zalloc().
No assumption can be made about object internals.

(lldb) run
Process 22135 launched: './miniruby' (x86_64)
Process 22135 stopped
* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
    frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
   1361         break;
   1362     }
   1363 #endif
-> 1364     return block->type;
   1365 }
   1366
   1367 static inline void
(lldb) bt
* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
  * frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
    frame #1: 0x000000010008acdb miniruby`vm_block_iseq(block=0x0000000000000000) + 24 at vm_core.h:1399
    frame #2: 0x000000010008acc1 miniruby`vm_proc_iseq(procval=4310866360) + 32 at vm_core.h:1387
    frame #3: 0x000000010009cbed miniruby`rb_raw_obj_info(buff="0x0000000100f299b8 [0    ] proc (Proc)", buff_size=256, obj=4310866360) + 1513 at gc.c:9349
    frame #4: 0x000000010009cf01 miniruby`obj_info(obj=4310866360) + 98 at gc.c:9428
    frame #5: 0x000000010008ca1b miniruby`newobj_init(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32, objspace=0x00000001007cf280, obj=4310866360) + 338 at gc.c:1887
    frame #6: 0x000000010008cce5 miniruby`newobj_of(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32) + 171 at gc.c:1970
    frame #7: 0x000000010008d01d miniruby`rb_data_typed_object_wrap(klass=4311027960, datap=0x0000000000000000, type=0x0000000100311d60) + 133 at gc.c:2062
    frame #8: 0x000000010008d04e miniruby`rb_data_typed_object_zalloc(klass=4311027960, size=40, type=0x0000000100311d60) + 42 at gc.c:2073
    frame #9: 0x000000010011b459 miniruby`rb_proc_alloc(klass=4311027960) + 36 at proc.c:113
    frame #10: 0x0000000100204d8e miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x00000001025003f8, block_type=block_type_iseq, is_from_method='\0', is_lambda='\x01') + 44 at vm.c:814
    frame #11: 0x00000001002050d8 miniruby`rb_vm_make_proc_lambda(ec=0x00000001007cf548, captured=0x00000001025003f8, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
    frame #12: 0x000000010011c0d2 miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
    frame #13: 0x000000010011c154 miniruby`rb_block_lambda + 27 at proc.c:808
    frame #14: 0x00000001001ee7e3 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000102400480) + 41 at vm_insnhelper.c:1729
    frame #15: 0x00000001001ef2c3 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 386 at vm_insnhelper.c:1918
    frame #16: 0x00000001001ef412 miniruby`vm_call_cfunc(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 149 at vm_insnhelper.c:1934
    frame #17: 0x00000001001f0655 miniruby`vm_call_method_each_type(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 239 at vm_insnhelper.c:2232
    frame #18: 0x00000001001f0ce0 miniruby`vm_call_method(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 117 at vm_insnhelper.c:2355
    frame #19: 0x00000001001f0eb6 miniruby`vm_call_general(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 59 at vm_insnhelper.c:2398
    frame #20: 0x00000001001f6e61 miniruby`vm_exec_core(ec=0x00000001007cf548, initial=0) + 7480 at insns.def:850
    frame #21: 0x0000000100207995 miniruby`vm_exec(ec=0x00000001007cf548) + 230 at vm.c:1771
    frame #22: 0x0000000100208647 miniruby`rb_iseq_eval_main(iseq=0x0000000100f29fd0) + 52 at vm.c:2019
    frame #23: 0x000000010007b750 miniruby`ruby_exec_internal(n=0x0000000100f29fd0) + 297 at eval.c:246
    frame #24: 0x000000010007b876 miniruby`ruby_exec_node(n=0x0000000100f29fd0) + 36 at eval.c:310
    frame #25: 0x000000010007b849 miniruby`ruby_run_node(n=0x0000000100f29fd0) + 62 at eval.c:302
    frame #26: 0x0000000100000c05 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
    frame #27: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61565 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This imemo_name is used uninitialized because the switch
above does not cover all possible imemo types.

(lldb) run
Process 26068 launched: './miniruby' (x86_64)
Process 26068 stopped
* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
    frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
libsystem_c.dylib`strlen:
->  0x7fff8a402132 <+18>: pcmpeqb (%rdi), %xmm0
    0x7fff8a402136 <+22>: pmovmskb %xmm0, %esi
    0x7fff8a40213a <+26>: andq   $0xf, %rcx
    0x7fff8a40213e <+30>: orq    $-0x1, %rax
(lldb) bt
* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
  * frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
    frame #1: 0x00000001001f1531 miniruby`BSD_vfprintf(fp=0x00007fff5fbfc9e0, fmt0="%s %s", ap=0x00007fff5fbfcbf0) + 5873 at vsnprintf.c:1026
    frame #2: 0x00000001001ef213 miniruby`ruby_do_vsnprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s", ap=0x00007fff5fbfcbf0) + 131 at sprintf.c:1285
    frame #3: 0x00000001001ef3ea miniruby`ruby_snprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s") + 426 at sprintf.c:1300
    frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
    frame #5: 0x00000001000b7bff miniruby`obj_info(obj=4310983760) + 95 at gc.c:9428
    frame #6: 0x00000001000c1658 miniruby`newobj_init(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1, objspace=0x00000001007ee280, obj=4310983760) + 424 at gc.c:1887
    frame #7: 0x00000001000b4469 miniruby`newobj_of(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1) + 217 at gc.c:1970
    frame #8: 0x00000001000b45eb miniruby`rb_imemo_new(type=imemo_ast, v1=0, v2=4303040512, v3=4310983800, v0=0) + 75 at gc.c:2017
    frame #9: 0x000000010011daed miniruby`rb_ast_new + 61 at node.c:1146
    frame #10: 0x0000000100160e15 miniruby`rb_parser_compile_file_path(vparser=4310984400, fname=4310984960, file=4310984080, start=1) + 53 at parse.y:5776
    frame #11: 0x00000001001e18ea miniruby`load_file_internal(argp_v=140734799795024) + 1834 at ruby.c:1907
    frame #12: 0x00000001000a1bb5 miniruby`rb_ensure(b_proc=(miniruby`load_file_internal at ruby.c:1795), data1=140734799795024, e_proc=(miniruby`restore_load_file at ruby.c:2007), data2=140734799795024) + 245 at eval.c:1037
    frame #13: 0x00000001001df4a4 miniruby`load_file(parser=4310984400, fname=4310984960, f=4310984080, script=1, opt=0x00007fff5fbfda28) + 100 at ruby.c:2026
    frame #14: 0x00000001001e084e miniruby`process_options(argc=0, argv=0x00007fff5fbfdc00, opt=0x00007fff5fbfda28) + 3454 at ruby.c:1682
    frame #15: 0x00000001001dfaae miniruby`ruby_process_options(argc=2, argv=0x00007fff5fbfdbf0) + 238 at ruby.c:2257
    frame #16: 0x000000010009ff43 miniruby`ruby_options(argc=2, argv=0x00007fff5fbfdbf0) + 211 at eval.c:105
    frame #17: 0x0000000100000989 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 105 at main.c:42
    frame #18: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb) up 4
frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
   9373 #undef IMEMO_NAME
   9374               default: UNREACHABLE;
   9375             }
-> 9376             snprintf(buff, buff_size, "%s %s", buff, imemo_name);
   9377
   9378             switch (imemo_type(obj)) {
   9379               case imemo_ment: {
(lldb) p imemo_name
(const char *) $0 = 0xffffffffffffffff
(lldb) p imemo_type(obj)
(imemo_type) $1 = imemo_ast
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61566 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

obj_info() assumes the given object is alive.  Passing freed
objects to it results in SEGV.

(lldb) run
Process 29718 launched: './miniruby' (x86_64)
Process 29718 stopped
* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
    frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
   266      }
   267      else {
   268          VM_ASSERT(RB_TYPE_P(pathobj, T_ARRAY));
-> 269          return RARRAY_AREF(pathobj, PATHOBJ_PATH);
   270      }
   271  }
   272
(lldb) bt
* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
  * frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
    frame #1: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x000000010af34a20) + 32 at iseq.c:723
    frame #2: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, iseq=0x000000010af34a20) + 69 at gc.c:9274
    frame #3: 0x000000010009e45a miniruby`rb_raw_obj_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, obj=4478683680) + 2191 at gc.c:9397
    frame #4: 0x000000010009e4d5 miniruby`obj_info(obj=4478683680) + 98 at gc.c:9429
    frame #5: 0x0000000100091ae3 miniruby`gc_page_sweep(objspace=0x00000001007d3280, heap=0x00000001007d32a0, sweep_page=0x000000010ae07bc0) + 622 at gc.c:3529
    frame #6: 0x000000010009206a miniruby`gc_sweep_step(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 188 at gc.c:3705
    frame #7: 0x0000000100092254 miniruby`gc_sweep_continue(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 133 at gc.c:3772
    frame #8: 0x000000010008d7f9 miniruby`heap_prepare(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 48 at gc.c:1746
    frame #9: 0x000000010008d8a1 miniruby`heap_get_freeobj_from_next_freepage(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 37 at gc.c:1769
    frame #10: 0x000000010008d98d miniruby`heap_get_freeobj(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 83 at gc.c:1803
    frame #11: 0x000000010008dcb0 miniruby`newobj_slowpath(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280, wb_protected=1) + 220 at gc.c:1930
    frame #12: 0x000000010008dd6c miniruby`newobj_slowpath_wb_protected(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280) + 76 at gc.c:1942
    frame #13: 0x000000010008dea1 miniruby`newobj_of(klass=4334386280, flags=5, v1=0, v2=0, v3=0, wb_protected=1) + 221 at gc.c:1974
    frame #14: 0x000000010008df39 miniruby`rb_wb_protected_newobj_of(klass=4334386280, flags=5) + 54 at gc.c:1990
    frame #15: 0x0000000100195f7c miniruby`str_alloc(klass=4334386280) + 29 at string.c:692
    frame #16: 0x0000000100195fe9 miniruby`str_new0(klass=4334386280, ptr="gitm", len=4, termlen=1) + 73 at string.c:714
    frame #17: 0x000000010019633e miniruby`rb_enc_str_new(ptr="gitm", len=4, enc=0x00000001025d50a0) + 81 at string.c:766
    frame #18: 0x000000010010a80a miniruby`parser_str_new(p="gitm", n=4, enc=0x00000001025d50a0, func=66, enc0=0x00000001025d50a0) + 50 at parse.y:5817
    frame #19: 0x000000010010ce1a miniruby`parser_parse_string(parser=0x00000001042ac5c0, quote=0x000000010460c028) + 795 at parse.y:6675
    frame #20: 0x00000001001120bd miniruby`parser_yylex(parser=0x00000001042ac5c0) + 159 at parse.y:8281
    frame #21: 0x0000000100115068 miniruby`yylex(lval=0x00007fff5fbf9948, yylloc=0x00007fff5fbf9ab0, parser=0x00000001042ac5c0) + 55 at parse.y:8931
    frame #22: 0x00000001000fc79f miniruby`ruby_yyparse(parser=0x00000001042ac5c0) + 1198 at parse.c:5798
    frame #23: 0x0000000100109f5a miniruby`yycompile0(arg=4364879296) + 317 at parse.y:5595
    frame #24: 0x0000000100214ef0 miniruby`rb_suppress_tracing(func=(miniruby`yycompile0 at parse.y:5565), arg=4364879296) + 349 at vm_trace.c:397
    frame #25: 0x000000010010a1df miniruby`yycompile(parser=0x00000001042ac5c0, fname=4443743440, line=1) + 126 at parse.y:5637
    frame #26: 0x000000010010a4c1 miniruby`parser_compile_string(vparser=4443743480, fname=4443743440, s=4443743520, line=1) + 191 at parse.y:5706
    frame #27: 0x000000010010a5b7 miniruby`rb_parser_compile_string_path(vparser=4443743480, f=4443743440, s=4443743520, line=1) + 58 at parse.y:5730
    frame #28: 0x0000000100206025 miniruby`eval_make_iseq(src=4443743520, fname=4443743440, line=1, bind=0x0000000000000000, base_block=0x00007fff5fbfb370) + 266 at vm_eval.c:1274
    frame #29: 0x0000000100206153 miniruby`eval_string_with_cref(self=4334412520, src=4443743520, cref=0x0000000000000000, file=52, line=1) + 197 at vm_eval.c:1307
    frame #30: 0x0000000100206389 miniruby`rb_f_eval(argc=1, argv=0x0000000102400eb8, self=4334412520) + 219 at vm_eval.c:1382
    frame #31: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_eval at vm_eval.c:1364), recv=4334412520, argc=1, argv=0x0000000102400eb8) + 47 at vm_insnhelper.c:1723
    frame #32: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 386 at vm_insnhelper.c:1918
    frame #33: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 149 at vm_insnhelper.c:1934
    frame #34: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
    frame #35: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #36: 0x00000001002093f8 miniruby`invoke_block(ec=0x00000001007d3548, iseq=0x000000010252d7f0, self=4334412520, captured=0x0000000102500df8, cref=0x0000000000000000, type=572653569, opt_pc=0) + 224 at vm.c:988
    frame #37: 0x0000000100209766 miniruby`invoke_iseq_block_from_c(ec=0x00000001007d3548, captured=0x0000000102500df8, self=4334412520, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0) + 389 at vm.c:1040
    frame #38: 0x0000000100209824 miniruby`invoke_block_from_c_bh(ec=0x00000001007d3548, block_handler=4333768185, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0, force_blockarg=0) + 138 at vm.c:1058
    frame #39: 0x00000001002099d0 miniruby`vm_yield(ec=0x00000001007d3548, argc=0, argv=0x0000000000000000) + 69 at vm.c:1103
    frame #40: 0x0000000100205623 miniruby`rb_yield_0(argc=0, argv=0x0000000000000000) + 40 at vm_eval.c:970
    frame #41: 0x0000000100205964 miniruby`loop_i + 19 at vm_eval.c:1049
    frame #42: 0x000000010007db07 miniruby`rb_rescue2(b_proc=(miniruby`loop_i at vm_eval.c:1047), data1=0, r_proc=(miniruby`loop_stop at vm_eval.c:1056), data2=0) + 369 at eval.c:896
    frame #43: 0x0000000100205a2e miniruby`rb_f_loop(self=4334412520) + 121 at vm_eval.c:1100
    frame #44: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_f_loop at vm_eval.c:1098), recv=4334412520, argc=0, argv=0x0000000102400e80) + 41 at vm_insnhelper.c:1729
    frame #45: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 386 at vm_insnhelper.c:1918
    frame #46: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 149 at vm_insnhelper.c:1934
    frame #47: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 239 at vm_insnhelper.c:2232
    frame #48: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 253 at vm_insnhelper.c:2366
    frame #49: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 59 at vm_insnhelper.c:2398
    frame #50: 0x00000001001fab2f miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 7480 at insns.def:850
    frame #51: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #52: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x000000010252dd90) + 52 at vm.c:2019
    frame #53: 0x000000010007c768 miniruby`ruby_exec_internal(n=0x000000010252dd90) + 297 at eval.c:246
    frame #54: 0x000000010007c88e miniruby`ruby_exec_node(n=0x000000010252dd90) + 36 at eval.c:310
    frame #55: 0x000000010007c861 miniruby`ruby_run_node(n=0x000000010252dd90) + 62 at eval.c:302
    frame #56: 0x000000010000138d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
    frame #57: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb) p ((struct RVALUE*)pathobj)->as.basic
(RBasic) $0 = (flags = 0, klass = 4478683600)
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61568 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

obj_info() assumes the given object is alive.  OTOH
gc_writebarrier_incremental is called before or in middle of
object initialization.  Can casue SEGV.

(lldb) run
Process 48188 launched: './miniruby' (x86_64)
Process 48188 stopped
* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
    frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
   2069 static inline const VALUE *
   2070 rb_array_const_ptr(VALUE a)
   2071 {
-> 2072     return FIX_CONST_VALUE_PTR((RBASIC(a)->flags & RARRAY_EMBED_FLAG) ?
   2073         RARRAY(a)->as.ary : RARRAY(a)->as.heap.ptr);
   2074 }
   2075
(lldb) bt
* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
  * frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
    frame #1: 0x00000001000bfaab miniruby`pathobj_path(pathobj=5251291222225483145) + 70 at vm_core.h:269
    frame #2: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x00000001025b71a8) + 32 at iseq.c:723
    frame #3: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, iseq=0x00000001025b71a8) + 69 at gc.c:9274
    frame #4: 0x000000010009e1d5 miniruby`rb_raw_obj_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, obj=4334514520) + 1546 at gc.c:9351
    frame #5: 0x000000010009e4d5 miniruby`obj_info(obj=4334514520) + 98 at gc.c:9429
    frame #6: 0x0000000100096658 miniruby`gc_writebarrier_incremental(a=4334514520, b=4334514600, objspace=0x00000001007d3280) + 61 at gc.c:5963
    frame #7: 0x00000001000968ca miniruby`rb_gc_writebarrier(a=4334514520, b=4334514600) + 127 at gc.c:6009
    frame #8: 0x00000001001eabe0 miniruby`rb_obj_written(a=4334514520, oldv=52, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 72 at ruby.h:1472
    frame #9: 0x00000001001eac2c miniruby`rb_obj_write(a=4334514520, slot=0x000000010259ff10, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 70 at ruby.h:1489
    frame #10: 0x0000000100208b6f miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x0000000102500338, block_type=block_type_ifunc, is_from_method='\0', is_lambda='\x01') + 137 at vm.c:821
    frame #11: 0x0000000100208e5c miniruby`rb_vm_make_proc_lambda(ec=0x00000001007d3548, captured=0x0000000102500338, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
    frame #12: 0x000000010011f08e miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
    frame #13: 0x000000010011f110 miniruby`rb_block_lambda + 27 at proc.c:808
    frame #14: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000000000000) + 41 at vm_insnhelper.c:1729
    frame #15: 0x00000001002033de miniruby`vm_call0_cfunc_with_frame(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 370 at vm_eval.c:85
    frame #16: 0x00000001002034d9 miniruby`vm_call0_cfunc(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 59 at vm_eval.c:100
    frame #17: 0x000000010020368f miniruby`vm_call0_body(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 436 at vm_eval.c:131
    frame #18: 0x000000010020326a miniruby`vm_call0(ec=0x00000001007d3548, recv=4310991600, id=2993, argc=0, argv=0x0000000000000000, me=0x0000000100f48110) + 142 at vm_eval.c:58
    frame #19: 0x0000000100203c60 miniruby`rb_call0(ec=0x00000001007d3548, recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL, self=4334514640) + 166 at vm_eval.c:296
    frame #20: 0x0000000100204827 miniruby`rb_call(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL) + 84 at vm_eval.c:589
    frame #21: 0x000000010020518b miniruby`rb_funcallv(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000) + 52 at vm_eval.c:815
    frame #22: 0x000000010012242e miniruby`mlambda(method=0) + 45 at proc.c:2661
    frame #23: 0x0000000100205bac miniruby`rb_iterate0(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, ifunc=0x00000001025b71a8, ec=0x00000001007d3548) + 380 at vm_eval.c:1134
    frame #24: 0x0000000100205d16 miniruby`rb_iterate(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, bl_proc=(miniruby`bmcall at proc.c:2666), data2=4334514640) + 88 at vm_eval.c:1166
    frame #25: 0x00000001001224c7 miniruby`method_to_proc(method=4334514640) + 43 at proc.c:2701
    frame #26: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`method_to_proc at proc.c:2688), recv=4334514640, argc=0, argv=0x0000000102400568) + 41 at vm_insnhelper.c:1729
    frame #27: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 386 at vm_insnhelper.c:1918
    frame #28: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 149 at vm_insnhelper.c:1934
    frame #29: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 239 at vm_insnhelper.c:2232
    frame #30: 0x00000001001f49a4 miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 117 at vm_insnhelper.c:2355
    frame #31: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 59 at vm_insnhelper.c:2398
    frame #32: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
    frame #33: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #34: 0x000000010020c3d1 miniruby`rb_iseq_eval(iseq=0x00000001007f8270) + 52 at vm.c:2008
    frame #35: 0x00000001000caa4a miniruby`rb_load_internal0(ec=0x00000001007d3548, fname=4310799960, wrap=0) + 631 at load.c:611
    frame #36: 0x00000001000cab36 miniruby`rb_load_internal(fname=4310799960, wrap=0) + 46 at load.c:642
    frame #37: 0x00000001000cae1d miniruby`rb_f_load(argc=1, argv=0x00000001024004b8) + 217 at load.c:710
    frame #38: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_load at load.c:695), recv=4311327440, argc=1, argv=0x00000001024004b8) + 47 at vm_insnhelper.c:1723
    frame #39: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 386 at vm_insnhelper.c:1918
    frame #40: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 149 at vm_insnhelper.c:1934
    frame #41: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 239 at vm_insnhelper.c:2232
    frame #42: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 253 at vm_insnhelper.c:2366
    frame #43: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 59 at vm_insnhelper.c:2398
    frame #44: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
    frame #45: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
    frame #46: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x0000000100f21240) + 52 at vm.c:2019
    frame #47: 0x000000010007c774 miniruby`ruby_exec_internal(n=0x0000000100f21240) + 297 at eval.c:246
    frame #48: 0x000000010007c89a miniruby`ruby_exec_node(n=0x0000000100f21240) + 36 at eval.c:310
    frame #49: 0x000000010007c86d miniruby`ruby_run_node(n=0x0000000100f21240) + 62 at eval.c:302
    frame #50: 0x0000000100001399 miniruby`main(argc=9, argv=0x00007fff5fbfdae0) + 113 at main.c:42
    frame #51: 0x00007fff88eda5ad libdyld.dylib`start + 1
(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61569 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	fix SEGV touching uninitialized memory

	This function can be called from boot_defclass().
	No assumption can be made about object internals.

	(lldb) run
	Process 2386 launched: './miniruby' (x86_64)
	Process 2386 stopped
	* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
	    frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
	   318  VALUE
	   319  rb_class_path_cached(VALUE klass)
	   320  {
	-> 321      st_table *ivtbl = RCLASS_IV_TBL(klass);
	   322      st_data_t n;
	   323
	   324      if (!ivtbl) return Qnil;
	(lldb) bt
	* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
	  * frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
	    frame #1: 0x000000010009cbd0 miniruby`rb_raw_obj_info(buff="0x0000000100fa5798 [2    ] T_CLASS", buff_size=256, obj=4311373720) + 1393 at gc.c:9341
	    frame #2: 0x000000010009cf16 miniruby`obj_info(obj=4311373720) + 98 at gc.c:9423
	    frame #3: 0x000000010008ca87 miniruby`newobj_init(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007cf280, obj=4311373720) + 338 at gc.c:1887
	    frame #4: 0x000000010008cd51 miniruby`newobj_of(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1) + 171 at gc.c:1970
	    frame #5: 0x000000010008ce1b miniruby`rb_wb_protected_newobj_of(klass=0, flags=66) + 54 at gc.c:1990
	    frame #6: 0x0000000100027563 miniruby`class_alloc(flags=2, klass=0) + 46 at class.c:165
	    frame #7: 0x000000010002761a miniruby`rb_class_boot(super=0) + 35 at class.c:203
	    frame #8: 0x0000000100028612 miniruby`boot_defclass(name="BasicObject", super=0) + 28 at class.c:537
	    frame #9: 0x000000010002868b miniruby`Init_class_hierarchy + 26 at class.c:548
	    frame #10: 0x00000001000efe69 miniruby`InitVM_Object + 9 at object.c:3892
	    frame #11: 0x00000001000f138e miniruby`Init_Object + 57 at object.c:4122
	    frame #12: 0x00000001000a59bd miniruby`rb_call_inits + 29 at inits.c:23
	    frame #13: 0x000000010007af30 miniruby`ruby_setup + 229 at eval.c:61
	    frame #14: 0x000000010007af7e miniruby`ruby_init + 13 at eval.c:78
	    frame #15: 0x0000000100000c58 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 88 at main.c:41
	    frame #16: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized memory

	This function can be called from InitVM_Object().
	No assumption can be made about object internals.

	(lldb) run
	Process 10675 launched: './miniruby' (x86_64)
	Process 10675 stopped
	* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	    frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
	   9380                 const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
	   9381                 snprintf(buff, buff_size, "%s (called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)", buff,
	   9382                          rb_id2name(me->called_id),
	-> 9383                          method_type_name(me->def->type),
	   9384                          me->def->alias_count,
	   9385                          obj_info(me->owner),
	   9386                          obj_info(me->defined_class));
	(lldb) p *me
	(rb_method_entry_t) $0 = {
	  flags = 24602
	  defined_class = 4311488400
	  def = 0x0000000000000000
	  called_id = 3057
	  owner = 4311488400
	}
	(lldb) bt
	* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	  * frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
	    frame #1: 0x00000001000b7cbf miniruby`obj_info(obj=4311487880) + 95 at gc.c:9423
	    frame #2: 0x00000001000c16a8 miniruby`newobj_init(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1, objspace=0x00000001007ee280, obj=4311487880) + 424 at gc.c:1887
	    frame #3: 0x00000001000b4529 miniruby`newobj_of(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1) + 217 at gc.c:1970
	    frame #4: 0x00000001000b46ab miniruby`rb_imemo_new(type=imemo_ment, v1=0, v2=3057, v3=4311488400, v0=4311488400) + 75 at gc.c:2017
	    frame #5: 0x00000001002773b4 miniruby`rb_method_entry_alloc(called_id=3057, owner=4311488400, defined_class=4311488400, def=0x0000000000000000) + 52 at vm_method.c:368
	    frame #6: 0x0000000100277307 miniruby`rb_method_entry_create(called_id=3057, klass=4311488400, visi=METHOD_VISI_PRIVATE, def=0x0000000000000000) + 71 at vm_method.c:389
	    frame #7: 0x00000001002784c7 miniruby`rb_method_entry_make(klass=4311488400, mid=3057, defined_class=4311488400, visi=METHOD_VISI_PRIVATE, type=VM_METHOD_TYPE_CFUNC, def=0x0000000000000000, original_id=3057, opts=0x00007fff5fbfd9e8) + 1207 at vm_method.c:594
	    frame #8: 0x00000001002770f9 miniruby`rb_add_method(klass=4311488400, mid=3057, type=VM_METHOD_TYPE_CFUNC, opts=0x00007fff5fbfd9e8, visi=METHOD_VISI_PRIVATE) + 73 at vm_method.c:650
	    frame #9: 0x000000010027708a miniruby`rb_add_method_cfunc(klass=4311488400, mid=3057, func=(miniruby`rb_obj_dummy at object.c:1125), argc=0, visi=METHOD_VISI_PRIVATE) + 138 at vm_method.c:137
	    frame #10: 0x00000001000391e4 miniruby`rb_define_private_method(klass=4311488400, name="initialize", func=(miniruby`rb_obj_dummy at object.c:1125), argc=0) + 68 at class.c:1529
	    frame #11: 0x000000010013f5bf miniruby`InitVM_Object + 47 at object.c:3905
	    frame #12: 0x0000000100142ffd miniruby`Init_Object + 61 at object.c:4122
	    frame #13: 0x00000001000d4edd miniruby`rb_call_inits + 29 at inits.c:23
	    frame #14: 0x000000010009fe66 miniruby`ruby_setup + 198 at eval.c:61
	    frame #15: 0x000000010009febd miniruby`ruby_init + 13 at eval.c:78
	    frame #16: 0x0000000100000a4d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
	    frame #17: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized local variable

	This imemo_name is used uninitialized because the switch
	above does not cover all possible imemo types.

	(lldb) run
	Process 26068 launched: './miniruby' (x86_64)
	Process 26068 stopped
	* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
	    frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
	libsystem_c.dylib`strlen:
	->  0x7fff8a402132 <+18>: pcmpeqb (%rdi), %xmm0
	    0x7fff8a402136 <+22>: pmovmskb %xmm0, %esi
	    0x7fff8a40213a <+26>: andq   $0xf, %rcx
	    0x7fff8a40213e <+30>: orq    $-0x1, %rax
	(lldb) bt
	* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
	  * frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
	    frame #1: 0x00000001001f1531 miniruby`BSD_vfprintf(fp=0x00007fff5fbfc9e0, fmt0="%s %s", ap=0x00007fff5fbfcbf0) + 5873 at vsnprintf.c:1026
	    frame #2: 0x00000001001ef213 miniruby`ruby_do_vsnprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s", ap=0x00007fff5fbfcbf0) + 131 at sprintf.c:1285
	    frame #3: 0x00000001001ef3ea miniruby`ruby_snprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s") + 426 at sprintf.c:1300
	    frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
	    frame #5: 0x00000001000b7bff miniruby`obj_info(obj=4310983760) + 95 at gc.c:9428
	    frame #6: 0x00000001000c1658 miniruby`newobj_init(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1, objspace=0x00000001007ee280, obj=4310983760) + 424 at gc.c:1887
	    frame #7: 0x00000001000b4469 miniruby`newobj_of(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1) + 217 at gc.c:1970
	    frame #8: 0x00000001000b45eb miniruby`rb_imemo_new(type=imemo_ast, v1=0, v2=4303040512, v3=4310983800, v0=0) + 75 at gc.c:2017
	    frame #9: 0x000000010011daed miniruby`rb_ast_new + 61 at node.c:1146
	    frame #10: 0x0000000100160e15 miniruby`rb_parser_compile_file_path(vparser=4310984400, fname=4310984960, file=4310984080, start=1) + 53 at parse.y:5776
	    frame #11: 0x00000001001e18ea miniruby`load_file_internal(argp_v=140734799795024) + 1834 at ruby.c:1907
	    frame #12: 0x00000001000a1bb5 miniruby`rb_ensure(b_proc=(miniruby`load_file_internal at ruby.c:1795), data1=140734799795024, e_proc=(miniruby`restore_load_file at ruby.c:2007), data2=140734799795024) + 245 at eval.c:1037
	    frame #13: 0x00000001001df4a4 miniruby`load_file(parser=4310984400, fname=4310984960, f=4310984080, script=1, opt=0x00007fff5fbfda28) + 100 at ruby.c:2026
	    frame #14: 0x00000001001e084e miniruby`process_options(argc=0, argv=0x00007fff5fbfdc00, opt=0x00007fff5fbfda28) + 3454 at ruby.c:1682
	    frame #15: 0x00000001001dfaae miniruby`ruby_process_options(argc=2, argv=0x00007fff5fbfdbf0) + 238 at ruby.c:2257
	    frame #16: 0x000000010009ff43 miniruby`ruby_options(argc=2, argv=0x00007fff5fbfdbf0) + 211 at eval.c:105
	    frame #17: 0x0000000100000989 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 105 at main.c:42
	    frame #18: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb) up 4
	frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
	   9373 #undef IMEMO_NAME
	   9374               default: UNREACHABLE;
	   9375             }
	-> 9376             snprintf(buff, buff_size, "%s %s", buff, imemo_name);
	   9377
	   9378             switch (imemo_type(obj)) {
	   9379               case imemo_ment: {
	(lldb) p imemo_name
	(const char *) $0 = 0xffffffffffffffff
	(lldb) p imemo_type(obj)
	(imemo_type) $1 = imemo_ast
	(lldb)

	fix SEGV inspecting already freed objects

	obj_info() assumes the given object is alive.  Passing freed
	objects to it results in SEGV.

	(lldb) run
	Process 29718 launched: './miniruby' (x86_64)
	Process 29718 stopped
	* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	    frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
	   266      }
	   267      else {
	   268          VM_ASSERT(RB_TYPE_P(pathobj, T_ARRAY));
	-> 269          return RARRAY_AREF(pathobj, PATHOBJ_PATH);
	   270      }
	   271  }
	   272
	(lldb) bt
	* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	  * frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
	    frame #1: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x000000010af34a20) + 32 at iseq.c:723
	    frame #2: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, iseq=0x000000010af34a20) + 69 at gc.c:9274
	    frame #3: 0x000000010009e45a miniruby`rb_raw_obj_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, obj=4478683680) + 2191 at gc.c:9397
	    frame #4: 0x000000010009e4d5 miniruby`obj_info(obj=4478683680) + 98 at gc.c:9429
	    frame #5: 0x0000000100091ae3 miniruby`gc_page_sweep(objspace=0x00000001007d3280, heap=0x00000001007d32a0, sweep_page=0x000000010ae07bc0) + 622 at gc.c:3529
	    frame #6: 0x000000010009206a miniruby`gc_sweep_step(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 188 at gc.c:3705
	    frame #7: 0x0000000100092254 miniruby`gc_sweep_continue(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 133 at gc.c:3772
	    frame #8: 0x000000010008d7f9 miniruby`heap_prepare(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 48 at gc.c:1746
	    frame #9: 0x000000010008d8a1 miniruby`heap_get_freeobj_from_next_freepage(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 37 at gc.c:1769
	    frame #10: 0x000000010008d98d miniruby`heap_get_freeobj(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 83 at gc.c:1803
	    frame #11: 0x000000010008dcb0 miniruby`newobj_slowpath(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280, wb_protected=1) + 220 at gc.c:1930
	    frame #12: 0x000000010008dd6c miniruby`newobj_slowpath_wb_protected(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280) + 76 at gc.c:1942
	    frame #13: 0x000000010008dea1 miniruby`newobj_of(klass=4334386280, flags=5, v1=0, v2=0, v3=0, wb_protected=1) + 221 at gc.c:1974
	    frame #14: 0x000000010008df39 miniruby`rb_wb_protected_newobj_of(klass=4334386280, flags=5) + 54 at gc.c:1990
	    frame #15: 0x0000000100195f7c miniruby`str_alloc(klass=4334386280) + 29 at string.c:692
	    frame #16: 0x0000000100195fe9 miniruby`str_new0(klass=4334386280, ptr="gitm", len=4, termlen=1) + 73 at string.c:714
	    frame #17: 0x000000010019633e miniruby`rb_enc_str_new(ptr="gitm", len=4, enc=0x00000001025d50a0) + 81 at string.c:766
	    frame #18: 0x000000010010a80a miniruby`parser_str_new(p="gitm", n=4, enc=0x00000001025d50a0, func=66, enc0=0x00000001025d50a0) + 50 at parse.y:5817
	    frame #19: 0x000000010010ce1a miniruby`parser_parse_string(parser=0x00000001042ac5c0, quote=0x000000010460c028) + 795 at parse.y:6675
	    frame #20: 0x00000001001120bd miniruby`parser_yylex(parser=0x00000001042ac5c0) + 159 at parse.y:8281
	    frame #21: 0x0000000100115068 miniruby`yylex(lval=0x00007fff5fbf9948, yylloc=0x00007fff5fbf9ab0, parser=0x00000001042ac5c0) + 55 at parse.y:8931
	    frame #22: 0x00000001000fc79f miniruby`ruby_yyparse(parser=0x00000001042ac5c0) + 1198 at parse.c:5798
	    frame #23: 0x0000000100109f5a miniruby`yycompile0(arg=4364879296) + 317 at parse.y:5595
	    frame #24: 0x0000000100214ef0 miniruby`rb_suppress_tracing(func=(miniruby`yycompile0 at parse.y:5565), arg=4364879296) + 349 at vm_trace.c:397
	    frame #25: 0x000000010010a1df miniruby`yycompile(parser=0x00000001042ac5c0, fname=4443743440, line=1) + 126 at parse.y:5637
	    frame #26: 0x000000010010a4c1 miniruby`parser_compile_string(vparser=4443743480, fname=4443743440, s=4443743520, line=1) + 191 at parse.y:5706
	    frame #27: 0x000000010010a5b7 miniruby`rb_parser_compile_string_path(vparser=4443743480, f=4443743440, s=4443743520, line=1) + 58 at parse.y:5730
	    frame #28: 0x0000000100206025 miniruby`eval_make_iseq(src=4443743520, fname=4443743440, line=1, bind=0x0000000000000000, base_block=0x00007fff5fbfb370) + 266 at vm_eval.c:1274
	    frame #29: 0x0000000100206153 miniruby`eval_string_with_cref(self=4334412520, src=4443743520, cref=0x0000000000000000, file=52, line=1) + 197 at vm_eval.c:1307
	    frame #30: 0x0000000100206389 miniruby`rb_f_eval(argc=1, argv=0x0000000102400eb8, self=4334412520) + 219 at vm_eval.c:1382
	    frame #31: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_eval at vm_eval.c:1364), recv=4334412520, argc=1, argv=0x0000000102400eb8) + 47 at vm_insnhelper.c:1723
	    frame #32: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 386 at vm_insnhelper.c:1918
	    frame #33: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 149 at vm_insnhelper.c:1934
	    frame #34: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #35: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #36: 0x00000001002093f8 miniruby`invoke_block(ec=0x00000001007d3548, iseq=0x000000010252d7f0, self=4334412520, captured=0x0000000102500df8, cref=0x0000000000000000, type=572653569, opt_pc=0) + 224 at vm.c:988
	    frame #37: 0x0000000100209766 miniruby`invoke_iseq_block_from_c(ec=0x00000001007d3548, captured=0x0000000102500df8, self=4334412520, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0) + 389 at vm.c:1040
	    frame #38: 0x0000000100209824 miniruby`invoke_block_from_c_bh(ec=0x00000001007d3548, block_handler=4333768185, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0, force_blockarg=0) + 138 at vm.c:1058
	    frame #39: 0x00000001002099d0 miniruby`vm_yield(ec=0x00000001007d3548, argc=0, argv=0x0000000000000000) + 69 at vm.c:1103
	    frame #40: 0x0000000100205623 miniruby`rb_yield_0(argc=0, argv=0x0000000000000000) + 40 at vm_eval.c:970
	    frame #41: 0x0000000100205964 miniruby`loop_i + 19 at vm_eval.c:1049
	    frame #42: 0x000000010007db07 miniruby`rb_rescue2(b_proc=(miniruby`loop_i at vm_eval.c:1047), data1=0, r_proc=(miniruby`loop_stop at vm_eval.c:1056), data2=0) + 369 at eval.c:896
	    frame #43: 0x0000000100205a2e miniruby`rb_f_loop(self=4334412520) + 121 at vm_eval.c:1100
	    frame #44: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_f_loop at vm_eval.c:1098), recv=4334412520, argc=0, argv=0x0000000102400e80) + 41 at vm_insnhelper.c:1729
	    frame #45: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 386 at vm_insnhelper.c:1918
	    frame #46: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 149 at vm_insnhelper.c:1934
	    frame #47: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 239 at vm_insnhelper.c:2232
	    frame #48: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 253 at vm_insnhelper.c:2366
	    frame #49: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 59 at vm_insnhelper.c:2398
	    frame #50: 0x00000001001fab2f miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 7480 at insns.def:850
	    frame #51: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #52: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x000000010252dd90) + 52 at vm.c:2019
	    frame #53: 0x000000010007c768 miniruby`ruby_exec_internal(n=0x000000010252dd90) + 297 at eval.c:246
	    frame #54: 0x000000010007c88e miniruby`ruby_exec_node(n=0x000000010252dd90) + 36 at eval.c:310
	    frame #55: 0x000000010007c861 miniruby`ruby_run_node(n=0x000000010252dd90) + 62 at eval.c:302
	    frame #56: 0x000000010000138d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
	    frame #57: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb) p ((struct RVALUE*)pathobj)->as.basic
	(RBasic) $0 = (flags = 0, klass = 4478683600)
	(lldb)

	fix SEGV inspecting uninitialized objects

	obj_info() assumes the given object is alive.  OTOH
	gc_writebarrier_incremental is called before or in middle of
	object initialization.  Can casue SEGV.

	(lldb) run
	Process 48188 launched: './miniruby' (x86_64)
	Process 48188 stopped
	* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
	    frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
	   2069 static inline const VALUE *
	   2070 rb_array_const_ptr(VALUE a)
	   2071 {
	-> 2072     return FIX_CONST_VALUE_PTR((RBASIC(a)->flags & RARRAY_EMBED_FLAG) ?
	   2073         RARRAY(a)->as.ary : RARRAY(a)->as.heap.ptr);
	   2074 }
	   2075
	(lldb) bt
	* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
	  * frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
	    frame #1: 0x00000001000bfaab miniruby`pathobj_path(pathobj=5251291222225483145) + 70 at vm_core.h:269
	    frame #2: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x00000001025b71a8) + 32 at iseq.c:723
	    frame #3: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, iseq=0x00000001025b71a8) + 69 at gc.c:9274
	    frame #4: 0x000000010009e1d5 miniruby`rb_raw_obj_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, obj=4334514520) + 1546 at gc.c:9351
	    frame #5: 0x000000010009e4d5 miniruby`obj_info(obj=4334514520) + 98 at gc.c:9429
	    frame #6: 0x0000000100096658 miniruby`gc_writebarrier_incremental(a=4334514520, b=4334514600, objspace=0x00000001007d3280) + 61 at gc.c:5963
	    frame #7: 0x00000001000968ca miniruby`rb_gc_writebarrier(a=4334514520, b=4334514600) + 127 at gc.c:6009
	    frame #8: 0x00000001001eabe0 miniruby`rb_obj_written(a=4334514520, oldv=52, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 72 at ruby.h:1472
	    frame #9: 0x00000001001eac2c miniruby`rb_obj_write(a=4334514520, slot=0x000000010259ff10, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 70 at ruby.h:1489
	    frame #10: 0x0000000100208b6f miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x0000000102500338, block_type=block_type_ifunc, is_from_method='\0', is_lambda='\x01') + 137 at vm.c:821
	    frame #11: 0x0000000100208e5c miniruby`rb_vm_make_proc_lambda(ec=0x00000001007d3548, captured=0x0000000102500338, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
	    frame #12: 0x000000010011f08e miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
	    frame #13: 0x000000010011f110 miniruby`rb_block_lambda + 27 at proc.c:808
	    frame #14: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000000000000) + 41 at vm_insnhelper.c:1729
	    frame #15: 0x00000001002033de miniruby`vm_call0_cfunc_with_frame(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 370 at vm_eval.c:85
	    frame #16: 0x00000001002034d9 miniruby`vm_call0_cfunc(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 59 at vm_eval.c:100
	    frame #17: 0x000000010020368f miniruby`vm_call0_body(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 436 at vm_eval.c:131
	    frame #18: 0x000000010020326a miniruby`vm_call0(ec=0x00000001007d3548, recv=4310991600, id=2993, argc=0, argv=0x0000000000000000, me=0x0000000100f48110) + 142 at vm_eval.c:58
	    frame #19: 0x0000000100203c60 miniruby`rb_call0(ec=0x00000001007d3548, recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL, self=4334514640) + 166 at vm_eval.c:296
	    frame #20: 0x0000000100204827 miniruby`rb_call(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL) + 84 at vm_eval.c:589
	    frame #21: 0x000000010020518b miniruby`rb_funcallv(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000) + 52 at vm_eval.c:815
	    frame #22: 0x000000010012242e miniruby`mlambda(method=0) + 45 at proc.c:2661
	    frame #23: 0x0000000100205bac miniruby`rb_iterate0(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, ifunc=0x00000001025b71a8, ec=0x00000001007d3548) + 380 at vm_eval.c:1134
	    frame #24: 0x0000000100205d16 miniruby`rb_iterate(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, bl_proc=(miniruby`bmcall at proc.c:2666), data2=4334514640) + 88 at vm_eval.c:1166
	    frame #25: 0x00000001001224c7 miniruby`method_to_proc(method=4334514640) + 43 at proc.c:2701
	    frame #26: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`method_to_proc at proc.c:2688), recv=4334514640, argc=0, argv=0x0000000102400568) + 41 at vm_insnhelper.c:1729
	    frame #27: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 386 at vm_insnhelper.c:1918
	    frame #28: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 149 at vm_insnhelper.c:1934
	    frame #29: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 239 at vm_insnhelper.c:2232
	    frame #30: 0x00000001001f49a4 miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 117 at vm_insnhelper.c:2355
	    frame #31: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 59 at vm_insnhelper.c:2398
	    frame #32: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #33: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #34: 0x000000010020c3d1 miniruby`rb_iseq_eval(iseq=0x00000001007f8270) + 52 at vm.c:2008
	    frame #35: 0x00000001000caa4a miniruby`rb_load_internal0(ec=0x00000001007d3548, fname=4310799960, wrap=0) + 631 at load.c:611
	    frame #36: 0x00000001000cab36 miniruby`rb_load_internal(fname=4310799960, wrap=0) + 46 at load.c:642
	    frame #37: 0x00000001000cae1d miniruby`rb_f_load(argc=1, argv=0x00000001024004b8) + 217 at load.c:710
	    frame #38: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_load at load.c:695), recv=4311327440, argc=1, argv=0x00000001024004b8) + 47 at vm_insnhelper.c:1723
	    frame #39: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 386 at vm_insnhelper.c:1918
	    frame #40: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 149 at vm_insnhelper.c:1934
	    frame #41: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 239 at vm_insnhelper.c:2232
	    frame #42: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 253 at vm_insnhelper.c:2366
	    frame #43: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 59 at vm_insnhelper.c:2398
	    frame #44: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #45: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #46: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x0000000100f21240) + 52 at vm.c:2019
	    frame #47: 0x000000010007c774 miniruby`ruby_exec_internal(n=0x0000000100f21240) + 297 at eval.c:246
	    frame #48: 0x000000010007c89a miniruby`ruby_exec_node(n=0x0000000100f21240) + 36 at eval.c:310
	    frame #49: 0x000000010007c86d miniruby`ruby_run_node(n=0x0000000100f21240) + 62 at eval.c:302
	    frame #50: 0x0000000100001399 miniruby`main(argc=9, argv=0x00007fff5fbfdae0) + 113 at main.c:42
	    frame #51: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@62023 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	fix SEGV touching uninitialized memory

	This function can be called from Init_VM().
	No assumption can be made about object internals.

	(lldb) run
	Process 15734 launched: './miniruby' (x86_64)
	Process 15734 stopped
	* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
	    frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
	   9270 static void
	   9271 rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
	   9272 {
	-> 9273     if (iseq->body->location.label) {
	   9274         VALUE path = rb_iseq_path(iseq);
	   9275         snprintf(buff, buff_size, "%s %s@%s:%d", buff,
	   9276                  RSTRING_PTR(iseq->body->location.label),
	(lldb) p *iseq
	(rb_iseq_t) $0 = {
	  flags = 28698
	  reserved1 = 0
	  body = 0x0000000000000000
	  aux = {
	    compile_data = 0x0000000000000000
	    loader = (obj = 0, index = 0)
	    trace_events = 0
	  }
	}
	(lldb) bt
	* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
	  * frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
	    frame #1: 0x00000001000bde72 miniruby`rb_raw_obj_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, obj=4311097160) + 2786 at gc.c:9396
	    frame #2: 0x00000001000b7c5f miniruby`obj_info(obj=4311097160) + 95 at gc.c:9428
	    frame #3: 0x00000001000c16a8 miniruby`newobj_init(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007ee280, obj=4311097160) + 424 at gc.c:1887
	    frame #4: 0x00000001000b44c9 miniruby`newobj_of(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1) + 217 at gc.c:1970
	    frame #5: 0x00000001000b464b miniruby`rb_imemo_new(type=imemo_iseq, v1=0, v2=0, v3=0, v0=0) + 75 at gc.c:2017
	    frame #6: 0x00000001000fd914 miniruby`iseq_imemo_alloc + 36 at iseq.h:156
	    frame #7: 0x00000001000f6e1d miniruby`iseq_alloc + 13 at iseq.c:211
	    frame #8: 0x00000001000f6bf8 miniruby`rb_iseq_new_with_opt(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, first_lineno=1, parent=0x0000000000000000, type=ISEQ_TYPE_TOP, option=0x0000000100335c30) + 56 at iseq.c:519
	    frame #9: 0x00000001000f6bb6 miniruby`rb_iseq_new(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, parent=0x0000000000000000, type=ISEQ_TYPE_TOP) + 86 at iseq.c:480
	    frame #10: 0x0000000100284bb0 miniruby`Init_VM + 1040 at vm.c:3022
	    frame #11: 0x00000001000d4f7d miniruby`rb_call_inits + 189 at inits.c:55
	    frame #12: 0x000000010009fe06 miniruby`ruby_setup + 198 at eval.c:61
	    frame #13: 0x000000010009fe5d miniruby`ruby_init + 13 at eval.c:78
	    frame #14: 0x00000001000009ed miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
	    frame #15: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized memory

	This function can be called from rb_data_typed_object_zalloc().
	No assumption can be made about object internals.

	(lldb) run
	Process 22135 launched: './miniruby' (x86_64)
	Process 22135 stopped
	* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
	    frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
	   1361         break;
	   1362     }
	   1363 #endif
	-> 1364     return block->type;
	   1365 }
	   1366
	   1367 static inline void
	(lldb) bt
	* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
	  * frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
	    frame #1: 0x000000010008acdb miniruby`vm_block_iseq(block=0x0000000000000000) + 24 at vm_core.h:1399
	    frame #2: 0x000000010008acc1 miniruby`vm_proc_iseq(procval=4310866360) + 32 at vm_core.h:1387
	    frame #3: 0x000000010009cbed miniruby`rb_raw_obj_info(buff="0x0000000100f299b8 [0    ] proc (Proc)", buff_size=256, obj=4310866360) + 1513 at gc.c:9349
	    frame #4: 0x000000010009cf01 miniruby`obj_info(obj=4310866360) + 98 at gc.c:9428
	    frame #5: 0x000000010008ca1b miniruby`newobj_init(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32, objspace=0x00000001007cf280, obj=4310866360) + 338 at gc.c:1887
	    frame #6: 0x000000010008cce5 miniruby`newobj_of(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32) + 171 at gc.c:1970
	    frame #7: 0x000000010008d01d miniruby`rb_data_typed_object_wrap(klass=4311027960, datap=0x0000000000000000, type=0x0000000100311d60) + 133 at gc.c:2062
	    frame #8: 0x000000010008d04e miniruby`rb_data_typed_object_zalloc(klass=4311027960, size=40, type=0x0000000100311d60) + 42 at gc.c:2073
	    frame #9: 0x000000010011b459 miniruby`rb_proc_alloc(klass=4311027960) + 36 at proc.c:113
	    frame #10: 0x0000000100204d8e miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x00000001025003f8, block_type=block_type_iseq, is_from_method='\0', is_lambda='\x01') + 44 at vm.c:814
	    frame #11: 0x00000001002050d8 miniruby`rb_vm_make_proc_lambda(ec=0x00000001007cf548, captured=0x00000001025003f8, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
	    frame #12: 0x000000010011c0d2 miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
	    frame #13: 0x000000010011c154 miniruby`rb_block_lambda + 27 at proc.c:808
	    frame #14: 0x00000001001ee7e3 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000102400480) + 41 at vm_insnhelper.c:1729
	    frame #15: 0x00000001001ef2c3 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 386 at vm_insnhelper.c:1918
	    frame #16: 0x00000001001ef412 miniruby`vm_call_cfunc(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 149 at vm_insnhelper.c:1934
	    frame #17: 0x00000001001f0655 miniruby`vm_call_method_each_type(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 239 at vm_insnhelper.c:2232
	    frame #18: 0x00000001001f0ce0 miniruby`vm_call_method(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 117 at vm_insnhelper.c:2355
	    frame #19: 0x00000001001f0eb6 miniruby`vm_call_general(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 59 at vm_insnhelper.c:2398
	    frame #20: 0x00000001001f6e61 miniruby`vm_exec_core(ec=0x00000001007cf548, initial=0) + 7480 at insns.def:850
	    frame #21: 0x0000000100207995 miniruby`vm_exec(ec=0x00000001007cf548) + 230 at vm.c:1771
	    frame #22: 0x0000000100208647 miniruby`rb_iseq_eval_main(iseq=0x0000000100f29fd0) + 52 at vm.c:2019
	    frame #23: 0x000000010007b750 miniruby`ruby_exec_internal(n=0x0000000100f29fd0) + 297 at eval.c:246
	    frame #24: 0x000000010007b876 miniruby`ruby_exec_node(n=0x0000000100f29fd0) + 36 at eval.c:310
	    frame #25: 0x000000010007b849 miniruby`ruby_run_node(n=0x0000000100f29fd0) + 62 at eval.c:302
	    frame #26: 0x0000000100000c05 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
	    frame #27: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	check an existence of block.

	* gc.c (rb_raw_obj_info): check block before using it.

	* vm_core.h (vm_block_iseq): r61565 introduced NULL check but this
	  check is only needed by `rb_raw_obj_info()` and it is called at GC
	  debug mode. Above fix for `rb_raw_obj_info()` solves this problem and
	  NULL check should not be needed any more.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@62095 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This is reported by @hasimo. Fixing a case like this:

 #0  __lll_lock_wait () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
 #1  0x00007fc7bd824dbd in __GI___pthread_mutex_lock (mutex=mutex@entry=0x55946d294440 <mjit_engine_mutex>) at ../nptl/pthread_mutex_lock.c:80               4
 #2  0x000055946cec54d9 in rb_native_mutex_lock (lock=lock@entry=0x55946d294440 <mjit_engine_mutex>) at thread_pthread.c:211
 #3  0x000055946cde10ca in CRITICAL_SECTION_START (msg=0x55946cfb5423 "mjit_gc_start_hook", level=4) at mjit.c:392
 #4  mjit_gc_start_hook () at mjit.c:412
 #5  0x000055946cda0dfe in gc_enter (event=0x55946cfaf91e "gc_rest", objspace=0x55946da51760) at gc.c:6623
 #6  gc_rest (objspace=objspace@entry=0x55946da51760) at gc.c:6515
 #7  0x000055946cd9f1cf in gc_rest (objspace=0x55946da51760) at gc.c:7841
 #8  objspace_malloc_increase (objspace=objspace@entry=0x55946da51760, new_size=<optimized out>, old_size=old_size@entry=0, type=type@entry=MEMOP_TYPE_MALLOC, mem=0x7fc7a4439010) at gc.c:7842
 #9  0x000055946cda1706 in objspace_malloc_fixup (size=<optimized out>, mem=0x7fc7a4439010, objspace=0x55946da51760) at gc.c:7910
 #10 objspace_xmalloc0 (objspace=0x55946da51760, size=<optimized out>, size@entry=3145728) at gc.c:7939
 #11 0x000055946cda3620 in ruby_xmalloc0 (size=3145728) at gc.c:8006
 #12 ruby_xmalloc (size=size@entry=3145728) at gc.c:8015
 #13 0x000055946ce93f4c in st_init_table_with_size (type=0x55946d28da30 <objhash>, size=<optimized out>) at st.c:602
 #14 0x000055946ce94287 in rebuild_table (tab=tab@entry=0x55946db669f0) at st.c:777
 #15 0x000055946ce963f7 in rebuild_table_if_necessary (tab=0x55946db669f0) at st.c:1139
 #16 st_add_direct_with_hash (hash=8577035585096733536, value=20, key=808451, tab=0x55946db669f0) at st.c:1207
 #17 st_update (tab=0x55946db669f0, key=key@entry=808451, func=<optimized out>, arg=140726472841392) at st.c:1512
 #18 0x000055946cda9e27 in tbl_update (optional_arg=<optimized out>, func=<optimized out>, key=<optimized out>, hash=<optimized out>) at hash.c:561
 #19 rb_hash_aset (hash=94095983218480, key=key@entry=808451, val=val@entry=20) at hash.c:1654
 #20 0x000055946cde243a in mjit_add_class_serial (class_serial=class_serial@entry=404225) at mjit.c:1414                    3
 #21 0x000055946cefcfab in rb_next_class_serial () at vm.c:321
 #22 0x000055946cf48324 in class_alloc (klass=<optimized out>, flags=28) at class.c:178
 #23 rb_include_class_new (module=module@entry=94096115733840, super=0) at class.c:820
 #24 0x000055946cf487ac in include_modules_at (klass=klass@entry=94096135960920, c=<optimized out>, module=<optimized out>, module@entry=94096115734160, search_super=search_super@entry=1) at class.c:913
 #25 0x000055946cf48ac8 in rb_include_module (klass=94096135960920, module=module@entry=94096115734160) at class.c:870
 #26 0x000055946cd84993 in rb_mod_append_features (module=94096115734160, include=<optimized out>) at eval.c:1178
 #27 0x000055946cf06829 in vm_call0_cfunc_with_frame (ci=0x7ffd6f6c9a20, cc=0x7ffd6f6c9ba0, argv=0x7ffd6f6c9ba0, calling=0x7ffd6f6c9a30, ec=0x55946da519c8) at vm_eval.c:87
 #28 vm_call0_cfunc (argv=0x7ffd6f6c9ba0, cc=0x7ffd6f6c9ba0, ci=0x7ffd6f6c9a20, calling=0x7ffd6f6c9a30, ec=0x55946da519c8) at vm_eval.c:102
 #29 vm_call0_body (ec=ec@entry=0x55946da519c8, calling=calling@entry=0x7ffd6f6c9ae0, ci=ci@entry=0x7ffd6f6c9ad0, cc=cc@entry=0x7ffd6f6c9b00, argv=argv@entry=0x7ffd6f6c9ba0) at vm_eval.c:133
 #30 0x000055946cf074b2 in vm_call0 (me=<optimized out>, argv=0x7ffd6f6c9ba0, argc=1, id=4849, recv=94096115734160, ec=0x55946da519c8) at vm_eval.c:60
 #31 rb_call0 (ec=0x55946da519c8, recv=94096115734160, mid=4849, mid@entry=94096135960920, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6c9ba0, scope=scope@entry=CALL_FCALL, self=94096135960920) at vm_eval.c:302
 #32 0x000055946cf07b9b in rb_call (scope=CALL_FCALL, argv=0x7ffd6f6c9ba0, argc=1, mid=94096135960920, recv=<optimized out>) at vm_eval.c:595
 #33 rb_funcallv (recv=<optimized out>, mid=mid@entry=4849, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6c9ba0) at vm_eval.c:825
 #34 0x000055946cd848a7 in rb_mod_include (argc=0, argv=0x7fc7bdb4fce8, module=94096135960920) at eval.c:1203
 #35 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x5594710c06b0, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4df00, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #36 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4df00, calling=<optimized out>, ci=0x5594710c06b0, cc=<optimized out>) at vm_insnhelper.c:1944
 #37 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #38 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #39 0x000055946cf035fc in invoke_block (captured=0x7ffd6f6ca0a0, opt_pc=<optimized out>, type=<optimized out>, cref=0x559476c23930, self=94096135960920, iseq=0x559471335ee0, ec=0x55946da519c8) at vm.c:1005
 #40 invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x7ffd6f6ca0a0, self=94096135960920, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x559476c23930, is_lambda=0) at vm.c:1057
 #41 0x000055946cf04520 in invoke_block_from_c_bh (ec=ec@entry=0x55946da519c8, block_handler=<optimized out>, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6ca108, cref=<optimized out>, is_lambda=<optimized out>, is_lambda@entry=0, force_blockarg=0, passed_block_handler=0) at vm.c:1075
 #42 0x000055946cf04958 in vm_yield_with_cref (is_lambda=0, cref=<optimized out>, argv=0x7ffd6f6ca108, argc=1, ec=0x55946da519c8) at vm.c:1112
 #43 yield_under (under=94096135960920, self=<optimized out>, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6ca108) at vm_eval.c:1572
 #44 0x000055946cf04b12 in rb_mod_module_exec (argc=argc@entry=1, argv=argv@entry=0x7ffd6f6ca108, mod=<optimized out>) at vm_eval.c:1770
 #45 0x000055946ce00fc6 in rb_mod_initialize (module=94096135960920) at object.c:1978
 #46 0x000055946cf06829 in vm_call0_cfunc_with_frame (ci=0x7ffd6f6ca130, cc=0x7fc7bdb4fc98, argv=0x7fc7bdb4fc98, calling=0x7ffd6f6ca140, ec=0x55946da519c8) at vm_eval.c:87
 #47 vm_call0_cfunc (argv=0x7fc7bdb4fc98, cc=0x7fc7bdb4fc98, ci=0x7ffd6f6ca130, calling=0x7ffd6f6ca140, ec=0x55946da519c8) at vm_eval.c:102
 #48 vm_call0_body (ec=ec@entry=0x55946da519c8, calling=calling@entry=0x7ffd6f6ca1f0, ci=ci@entry=0x7ffd6f6ca1e0, cc=cc@entry=0x7ffd6f6ca210, argv=argv@entry=0x7fc7bdb4fc98) at vm_eval.c:133
 #49 0x000055946cf074b2 in vm_call0 (me=<optimized out>, argv=0x7fc7bdb4fc98, argc=0, id=3057, recv=94096135960920, ec=0x55946da519c8) at vm_eval.c:60
 #50 rb_call0 (ec=0x55946da519c8, recv=recv@entry=94096135960920, mid=mid@entry=3057, argc=argc@entry=3057, argv=argv@entry=0x0, scope=scope@entry=CALL_FCALL, self=94095983466120) at vm_eval.c:302
 #51 0x000055946cf07b9b in rb_call (scope=CALL_FCALL, argv=0x0, argc=3057, mid=3057, recv=94096135960920) at vm_eval.c:595
 #52 rb_funcallv (recv=recv@entry=94096135960920, mid=mid@entry=3057, argc=argc@entry=0, argv=argv@entry=0x7fc7bdb4fc98) at vm_eval.c:825
 #53 0x000055946cd89673 in rb_obj_call_init (obj=obj@entry=94096135960920, argc=argc@entry=0, argv=argv@entry=0x7fc7bdb4fc98) at eval.c:1590
 #54 0x000055946ce048a1 in rb_class_s_new (argc=0, argv=0x7fc7bdb4fc98, klass=<optimized out>) at object.c:2153
 #55 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x559471339c80, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4dfa8, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #56 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4dfa8, calling=<optimized out>, ci=0x559471339c80, cc=<optimized out>) at vm_insnhelper.c:1944
 #57 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #58 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #59 0x000055946cf03274 in invoke_bmethod (ec=ec@entry=0x55946da519c8, iseq=iseq@entry=0x55946f15cbc0, self=self@entry=94096115734640, me=me@entry=0x559475664e28, type=type@entry=572653825, opt_pc=0, captured=0x55947158e8a0) at vm.c:1026
 #60 0x000055946cf03534 in invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x55947158e8a0, self=94096115734640, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x0, is_lambda=1) at vm.c:1060
 #61 0x000055946cf036ce in invoke_block_from_c_proc (ec=<optimized out>, proc=<optimized out>, self=<optimized out>, argc=1, argv=<optimized out>, passed_block_handler=<optimized out>, is_lambda=<optimized out>) at vm.c:1150
 #62 0x000055946cf03811 in vm_invoke_bmethod (block_handler=<optimized out>, argv=<optimized out>, argc=1, self=<optimized out>, proc=<optimized out>, ec=0x55946da519c8) at vm.c:1175
 #63 vm_call_bmethod_body (ci=<optimized out>, cc=0x55946f625960, argv=<optimized out>, calling=0x7ffd6f6ca9b0, ec=0x55946da519c8) at vm_insnhelper.c:1971
 #64 vm_call_bmethod (ec=0x55946da519c8, cfp=0x7fc7bdc4e0c0, calling=0x7ffd6f6ca9b0, ci=<optimized out>, cc=0x55946f625960) at vm_insnhelper.c:1988
 #65 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4e0c0, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #66 0x000055946cf0e63e in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:797
 #67 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #68 0x000055946cf06767 in vm_call0_body (ec=ec@entry=0x55946da519c8, calling=calling@entry=0x7ffd6f6cad00, ci=ci@entry=0x7ffd6f6cacf0, cc=cc@entry=0x7ffd6f6cad20, argv=argv@entry=0x7ffd6f6cadb0) at vm_eval.c:129
 #69 0x000055946cf074b2 in vm_call0 (me=<optimized out>, argv=0x7ffd6f6cadb0, argc=1, id=3681, recv=94096115734640, ec=0x55946da519c8) at vm_eval.c:60
 #70 rb_call0 (ec=0x55946da519c8, recv=recv@entry=94096115734640, mid=3681, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6cad90, scope=scope@entry=CALL_FCALL, self=94095983452880) at vm_eval.c:302
 #71 0x000055946cf07b9b in rb_call (scope=CALL_FCALL, argv=0x7ffd6f6cad90, argc=1, mid=<optimized out>, recv=94096115734640) at vm_eval.c:595
 #72 rb_funcallv (recv=recv@entry=94096115734640, mid=<optimized out>, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6cadb0) at vm_eval.c:825
 #73 0x000055946cf477d2 in rb_class_inherited (super=super@entry=94096115734640, klass=klass@entry=94096135961440) at class.c:625
 #74 0x000055946cf0f796 in vm_declare_class (super=<optimized out>, cbase=94096094868200, flags=<optimized out>, id=847387) at vm_insnhelper.c:3134
 #75 vm_define_class (super=<optimized out>, cbase=<optimized out>, flags=<optimized out>, id=847387) at vm_insnhelper.c:3167
 #76 vm_find_or_create_class_by_id (super=<optimized out>, cbase=<optimized out>, flags=<optimized out>, id=847387) at vm_insnhelper.c:3196
 #77 vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:685
 #78 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #79 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x559471f1b548) at vm.c:2046
 #80 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94096135872160, wrap=wrap@entry=0) at load.c:611
 #81 0x000055946cdd41f1 in rb_require_internal (fname=94096135872400, fname@entry=94096135872440, safe=0) at load.c:992
 #82 0x000055946cdd4493 in rb_require_safe (safe=<optimized out>, fname=94096135872440) at load.c:1038
 #83 rb_f_require (obj=<optimized out>, fname=94096135872440) at load.c:820
 #84 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x5594708700a0, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e168, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #85 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e168, calling=<optimized out>, ci=0x5594708700a0, cc=<optimized out>) at vm_insnhelper.c:1944
 #86 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4e168, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #87 0x000055946cf0e63e in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:797
 #88 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #89 0x000055946cf035fc in invoke_block (captured=0x7fc7bdc4e490, opt_pc=<optimized out>, type=<optimized out>, cref=0x0, self=94096096426480, iseq=0x55946e49f0b8, ec=0x55946da519c8) at vm.c:1005
 #90 invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x7fc7bdc4e490, self=94096096426480, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x0, is_lambda=0) at vm.c:1057
 #91 0x000055946cf04699 in invoke_block_from_c_bh (argc=<optimized out>, passed_block_handler=<optimized out>, cref=<optimized out>, is_lambda=<optimized out>, force_blockarg=<optimized out>, argv=<optimized out>, block_handler=<optimized out>, ec=<optimized out>) at vm.c:1075
 #92 vm_yield (argc=1, argv=0x7ffd6f6cb938, ec=<optimized out>) at vm.c:1120
 #93 rb_yield_0 (argv=0x7ffd6f6cb938, argc=1) at vm_eval.c:980
 #94 rb_yield_1 (val=94096130169040) at vm_eval.c:986
 #95 rb_yield (val=<optimized out>) at vm_eval.c:996
 #96 0x000055946cf2113d in rb_ary_each (ary=94096076222560) at array.c:1820
 #97 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946ed0d090, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e478, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #98 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e478, calling=<optimized out>, ci=0x55946ed0d090, cc=<optimized out>) at vm_insnhelper.c:1944
 #99 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #100 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #101 0x000055946cf035fc in invoke_block (captured=0x7fc7bdc4e500, opt_pc=<optimized out>, type=<optimized out>, cref=0x0, self=94096096426480, iseq=0x55946e49f298, ec=0x55946da519c8) at vm.c:1005
 #102 invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x7fc7bdc4e500, self=94096096426480, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x0, is_lambda=0) at vm.c:1057
 #103 0x000055946cf04699 in invoke_block_from_c_bh (argc=<optimized out>, passed_block_handler=<optimized out>, cref=<optimized out>, is_lambda=<optimized out>, force_blockarg=<optimized out>, argv=<optimized out>, block_handler=<optimized out>, ec=<optimized out>) at vm.c:1075
 #104 vm_yield (argc=1, argv=0x7ffd6f6cbdf8, ec=<optimized out>) at vm.c:1120
 #105 rb_yield_0 (argv=0x7ffd6f6cbdf8, argc=1) at vm_eval.c:980
 #106 rb_yield_1 (val=94096095502480) at vm_eval.c:986
 #107 rb_yield (val=<optimized out>) at vm_eval.c:996
 #108 0x000055946cf2113d in rb_ary_each (ary=94096095328480) at array.c:1820
 #109 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e8552a0, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e4e8, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #110 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e4e8, calling=<optimized out>, ci=0x55946e8552a0, cc=<optimized out>) at vm_insnhelper.c:1944
 #111 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #112 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #113 0x000055946cf06767 in vm_call0_body (ec=ec@entry=0x55946da519c8, calling=calling@entry=0x7ffd6f6cc2d0, ci=ci@entry=0x7ffd6f6cc2c0, cc=cc@entry=0x7ffd6f6cc2f0, argv=argv@entry=0x7ffd6f6cc390) at vm_eval.c:129
 #114 0x000055946cf074b2 in vm_call0 (me=<optimized out>, argv=0x7ffd6f6cc390, argc=0, id=135807, recv=94096096186440, ec=0x55946da519c8) at vm_eval.c:60
 #115 rb_call0 (ec=0x55946da519c8, recv=94096096186440, mid=135807, argc=<optimized out>, argv=argv@entry=0x8, scope=scope@entry=CALL_PUBLIC, self=94095993048320) at vm_eval.c:302
 #116 0x000055946cf0a31a in rb_call (scope=CALL_PUBLIC, argv=0x8, argc=<optimized out>, mid=<optimized out>, recv=<optimized out>) at vm_eval.c:595
 #117 rb_funcall_with_block (recv=<optimized out>, mid=<optimized out>, argc=argc@entry=0, argv=argv@entry=0x7ffd6f6cc390, passed_procval=passed_procval@entry=8) at vm_eval.c:857
 #118 0x000055946ceb319c in rb_sym_proc_call (mid=<optimized out>, argc=argc@entry=1, argv=argv@entry=0x7ffd6f6cc388, passed_proc=passed_proc@entry=8) at string.c:10480
 #119 0x000055946cf0477c in vm_yield_with_symbol (block_handler=0, argv=0x7ffd6f6cc388, argc=1, symbol=<optimized out>, ec=<optimized out>) at vm_insnhelper.c:2573
 #120 invoke_block_from_c_bh (argc=<optimized out>, passed_block_handler=<optimized out>, cref=<optimized out>, is_lambda=<optimized out>, force_blockarg=<optimized out>, argv=<optimized out>, block_handler=<optimized out>, ec=<optimized out>) at vm.c:1084
 #121 vm_yield (argc=1, argv=0x7ffd6f6cc388, ec=<optimized out>) at vm.c:1120
 #122 rb_yield_0 (argv=0x7ffd6f6cc388, argc=1) at vm_eval.c:980
 #123 rb_yield_1 (val=94096096186440) at vm_eval.c:986
 #124 rb_yield (val=<optimized out>) at vm_eval.c:996
 #125 0x000055946cf2113d in rb_ary_each (ary=94095993048320) at array.c:1820
 #126 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x5594744d8280, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e590, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #127 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e590, calling=<optimized out>, ci=0x5594744d8280, cc=<optimized out>) at vm_insnhelper.c:1944
 #128 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4e590, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #129 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #130 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #131 0x000055946cf035fc in invoke_block (captured=0x7ffd6f6cc8e0, opt_pc=<optimized out>, type=<optimized out>, cref=0x559474604128, self=94096096426480, iseq=0x5594745027e8, ec=0x55946da519c8) at vm.c:1005
 #132 invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x7ffd6f6cc8e0, self=94096096426480, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x559474604128, is_lambda=0) at vm.c:1057
 #133 0x000055946cf04520 in invoke_block_from_c_bh (ec=ec@entry=0x55946da519c8, block_handler=<optimized out>, argc=argc@entry=1, argv=argv@entry=0x7fc7bdb4f7f8, cref=<optimized out>, is_lambda=<optimized out>, is_lambda@entry=0, force_blockarg=0, passed_block_handler=0) at vm.c:1075
 #134 0x000055946cf04958 in vm_yield_with_cref (is_lambda=0, cref=<optimized out>, argv=0x7fc7bdb4f7f8, argc=1, ec=0x55946da519c8) at vm.c:1112
 #135 yield_under (under=94096093646040, self=<optimized out>, argc=1, argv=0x7fc7bdb4f7f8) at vm_eval.c:1572
 #136 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e5cd230, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e600, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #137 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e600, calling=<optimized out>, ci=0x55946e5cd230, cc=<optimized out>) at vm_insnhelper.c:1944
 #138 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #139 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #140 0x000055946cf035fc in invoke_block (captured=0x5594744c4fb0, opt_pc=<optimized out>, type=<optimized out>, cref=0x0, self=94095990659320, iseq=0x55946e192aa0, ec=0x55946da519c8) at vm.c:1005
 #141 invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x5594744c4fb0, self=94095990659320, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x0, is_lambda=0) at vm.c:1057
 #142 0x000055946cf04699 in invoke_block_from_c_bh (argc=<optimized out>, passed_block_handler=<optimized out>, cref=<optimized out>, is_lambda=<optimized out>, force_blockarg=<optimized out>, argv=<optimized out>, block_handler=<optimized out>, ec=<optimized out>) at vm.c:1075
 #143 vm_yield (argc=1, argv=0x7ffd6f6ccdc8, ec=<optimized out>) at vm.c:1120
 #144 rb_yield_0 (argv=0x7ffd6f6ccdc8, argc=1) at vm_eval.c:980
 #145 rb_yield_1 (val=94096094867920) at vm_eval.c:986
 #146 rb_yield (val=<optimized out>) at vm_eval.c:996
 #147 0x000055946cf2113d in rb_ary_each (ary=94096094867160) at array.c:1820
 #148 0x000055946cf06829 in vm_call0_cfunc_with_frame (ci=0x7ffd6f6cce00, cc=0x7ffd6f6cce70, argv=0x7fc7bdb4f6b8, calling=0x7ffd6f6cce50, ec=0x55946da519c8) at vm_eval.c:87
 #149 vm_call0_cfunc (argv=0x7fc7bdb4f6b8, cc=0x7ffd6f6cce70, ci=0x7ffd6f6cce00, calling=0x7ffd6f6cce50, ec=0x55946da519c8) at vm_eval.c:102
 #150 vm_call0_body (ec=0x55946da519c8, calling=calling@entry=0x7ffd6f6ccec0, ci=ci@entry=0x7ffd6f6cceb0, cc=cc@entry=0x7ffd6f6ccee0, argv=0x7fc7bdb4f6b8) at vm_eval.c:133
 #151 0x000055946cf06c50 in vm_call0 (me=<optimized out>, argv=<optimized out>, argc=<optimized out>, id=<optimized out>, recv=<optimized out>, ec=<optimized out>) at vm_eval.c:60
 #152 rb_vm_call (ec=<optimized out>, recv=<optimized out>, id=<optimized out>, argc=<optimized out>, argv=<optimized out>, me=<optimized out>) at vm_eval.c:209
 #153 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946dba2780, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e7c0, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #154 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e7c0, calling=<optimized out>, ci=0x55946dba2780, cc=<optimized out>) at vm_insnhelper.c:1944
 #155 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4e7c0, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #156 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #157 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #158 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x55946dfed3a8) at vm.c:2046
 #159 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94095988939080, wrap=wrap@entry=0) at load.c:611
 #160 0x000055946cdd41f1 in rb_require_internal (fname=94095988939160, fname@entry=94095988939200, safe=0) at load.c:992
 #161 0x000055946cdd4493 in rb_require_safe (safe=<optimized out>, fname=94095988939200) at load.c:1038
 #162 rb_f_require (obj=<optimized out>, fname=94095988939200) at load.c:820
 #163 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946dffa920, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e948, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #164 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e948, calling=<optimized out>, ci=0x55946dffa920, cc=<optimized out>) at vm_insnhelper.c:1944
 #165 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4e948, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #166 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #167 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #168 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x55946dfee438) at vm.c:2046
 #169 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94095993039280, wrap=wrap@entry=0) at load.c:611
 #170 0x000055946cdd41f1 in rb_require_internal (fname=fname@entry=94095993043840, safe=0) at load.c:992
 #171 0x000055946cdd4493 in rb_require_safe (safe=<optimized out>, fname=94095993043840) at load.c:1038
 #172 rb_f_require (obj=<optimized out>, fname=94095993043840) at load.c:820
 #173 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946ea12160, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4e9b8, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #174 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4e9b8, calling=<optimized out>, ci=0x55946ea12160, cc=<optimized out>) at vm_insnhelper.c:1944
 #175 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4e9b8, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #176 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #177 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #178 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x55946e3d7c48) at vm.c:2046
 #179 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94095988920840, wrap=<optimized out>) at load.c:611
 #180 0x000055946cdd2850 in rb_load_internal (wrap=0, fname=94095988920840) at load.c:642
 #181 rb_f_load (argc=<optimized out>, argv=<optimized out>) at load.c:710
 #182 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e7c96e0, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4ea28, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #183 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4ea28, calling=<optimized out>, ci=0x55946e7c96e0, cc=<optimized out>) at vm_insnhelper.c:1944
 #184 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4ea28, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #185 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #186 0x000055946cf02f4c in vm_exec (ec=ec@entry=0x55946da519c8) at vm.c:1804
 #187 0x000055946cf035fc in invoke_block (captured=0x7fc7bdc4eae8, opt_pc=<optimized out>, type=<optimized out>, cref=0x0, self=94095998891400, iseq=0x55946e4dae10, ec=0x55946da519c8) at vm.c:1005
 #188 invoke_iseq_block_from_c (ec=0x55946da519c8, captured=0x7fc7bdc4eae8, self=94095998891400, argc=<optimized out>, argv=<optimized out>, passed_block_handler=0, cref=0x0, is_lambda=0) at vm.c:1057
 #189 0x000055946cf04699 in invoke_block_from_c_bh (argc=<optimized out>, passed_block_handler=<optimized out>, cref=<optimized out>, is_lambda=<optimized out>, force_blockarg=<optimized out>, argv=<optimized out>, block_handler=<optimized out>, ec=<optimized out>) at vm.c:1075
 #190 vm_yield (argc=1, argv=0x7ffd6f6ce8e8, ec=<optimized out>) at vm.c:1120
 #191 rb_yield_0 (argv=0x7ffd6f6ce8e8, argc=1) at vm_eval.c:980
 #192 rb_yield_1 (val=94095988924840) at vm_eval.c:986
 #193 rb_yield (val=<optimized out>) at vm_eval.c:996
 #194 0x000055946cf2113d in rb_ary_each (ary=94095988920960) at array.c:1820
 #195 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e421000, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4ead0, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #196 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4ead0, calling=<optimized out>, ci=0x55946e421000, cc=<optimized out>) at vm_insnhelper.c:1944
 #197 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4ead0, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #198 0x000055946cf0cb05 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:716
 #199 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #200 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x55946e35f2c0) at vm.c:2046
 #201 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94095992643280, wrap=<optimized out>) at load.c:611
 #202 0x000055946cdd2850 in rb_load_internal (wrap=0, fname=94095992643280) at load.c:642
 #203 rb_f_load (argc=<optimized out>, argv=<optimized out>) at load.c:710
 #204 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e24bb20, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4ec58, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #205 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4ec58, calling=<optimized out>, ci=0x55946e24bb20, cc=<optimized out>) at vm_insnhelper.c:1944
 #206 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4ec58, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #207 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #208 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #209 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x55946e3a7390) at vm.c:2046
 #210 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94095993616120, wrap=<optimized out>) at load.c:611
 #211 0x000055946cdd2850 in rb_load_internal (wrap=0, fname=94095993616120) at load.c:642
 #212 rb_f_load (argc=<optimized out>, argv=<optimized out>) at load.c:710
 #213 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e6a00d0, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4ecc8, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #214 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4ecc8, calling=<optimized out>, ci=0x55946e6a00d0, cc=<optimized out>) at vm_insnhelper.c:1944
 #215 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4ecc8, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #216 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #217 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #218 0x000055946cf118d1 in rb_iseq_eval (iseq=iseq@entry=0x55946e470100) at vm.c:2046
 #219 0x000055946cdd2164 in rb_load_internal0 (ec=ec@entry=0x55946da519c8, fname=fname@entry=94095993672200, wrap=<optimized out>) at load.c:611
 #220 0x000055946cdd2850 in rb_load_internal (wrap=0, fname=94095993672200) at load.c:642
 #221 rb_f_load (argc=<optimized out>, argv=<optimized out>) at load.c:710
 #222 0x000055946cefb61f in vm_call_cfunc_with_frame (ci=0x55946e3306a0, cc=<optimized out>, calling=<optimized out>, reg_cfp=0x7fc7bdc4efa0, ec=0x55946da519c8) at vm_insnhelper.c:1928
 #223 vm_call_cfunc (ec=0x55946da519c8, reg_cfp=0x7fc7bdc4efa0, calling=<optimized out>, ci=0x55946e3306a0, cc=<optimized out>) at vm_insnhelper.c:1944
 #224 0x000055946cf03ea3 in vm_call_method (ec=0x55946da519c8, cfp=0x7fc7bdc4efa0, calling=<optimized out>, ci=<optimized out>, cc=<optimized out>) at vm_insnhelper.c:2417
 #225 0x000055946cf0b5c2 in vm_exec_core (ec=ec@entry=0x55946da519c8, initial=initial@entry=0) at /tmp/ruby-build.20180216151216.13740/ruby-trunk/insns.def:779
 #226 0x000055946cf02f4c in vm_exec (ec=0x55946da519c8) at vm.c:1804
 #227 0x000055946cf119d5 in rb_iseq_eval_main (iseq=iseq@entry=0x55946e4bbba0) at vm.c:2057
 #228 0x000055946cd83d54 in ruby_exec_internal (n=0x55946e4bbba0) at eval.c:247
 #229 0x000055946cd87fdf in ruby_exec_node (n=0x55946e4bbba0) at eval.c:311
 #230 ruby_run_node (n=<optimized out>) at eval.c:303
 #231 0x000055946cd831bf in main (argc=22, argv=0x7ffd6f6d0148) at ./main.c:42

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62433 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	fix SEGV touching uninitialized memory

	This function can be called from boot_defclass().
	No assumption can be made about object internals.

	(lldb) run
	Process 2386 launched: './miniruby' (x86_64)
	Process 2386 stopped
	* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
	    frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
	   318  VALUE
	   319  rb_class_path_cached(VALUE klass)
	   320  {
	-> 321      st_table *ivtbl = RCLASS_IV_TBL(klass);
	   322      st_data_t n;
	   323
	   324      if (!ivtbl) return Qnil;
	(lldb) bt
	* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
	  * frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
	    frame #1: 0x000000010009cbd0 miniruby`rb_raw_obj_info(buff="0x0000000100fa5798 [2    ] T_CLASS", buff_size=256, obj=4311373720) + 1393 at gc.c:9341
	    frame #2: 0x000000010009cf16 miniruby`obj_info(obj=4311373720) + 98 at gc.c:9423
	    frame #3: 0x000000010008ca87 miniruby`newobj_init(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007cf280, obj=4311373720) + 338 at gc.c:1887
	    frame #4: 0x000000010008cd51 miniruby`newobj_of(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1) + 171 at gc.c:1970
	    frame #5: 0x000000010008ce1b miniruby`rb_wb_protected_newobj_of(klass=0, flags=66) + 54 at gc.c:1990
	    frame #6: 0x0000000100027563 miniruby`class_alloc(flags=2, klass=0) + 46 at class.c:165
	    frame #7: 0x000000010002761a miniruby`rb_class_boot(super=0) + 35 at class.c:203
	    frame #8: 0x0000000100028612 miniruby`boot_defclass(name="BasicObject", super=0) + 28 at class.c:537
	    frame #9: 0x000000010002868b miniruby`Init_class_hierarchy + 26 at class.c:548
	    frame #10: 0x00000001000efe69 miniruby`InitVM_Object + 9 at object.c:3892
	    frame #11: 0x00000001000f138e miniruby`Init_Object + 57 at object.c:4122
	    frame #12: 0x00000001000a59bd miniruby`rb_call_inits + 29 at inits.c:23
	    frame #13: 0x000000010007af30 miniruby`ruby_setup + 229 at eval.c:61
	    frame #14: 0x000000010007af7e miniruby`ruby_init + 13 at eval.c:78
	    frame #15: 0x0000000100000c58 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 88 at main.c:41
	    frame #16: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized memory

	This function can be called from InitVM_Object().
	No assumption can be made about object internals.

	(lldb) run
	Process 10675 launched: './miniruby' (x86_64)
	Process 10675 stopped
	* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	    frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
	   9380                 const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
	   9381                 snprintf(buff, buff_size, "%s (called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)", buff,
	   9382                          rb_id2name(me->called_id),
	-> 9383                          method_type_name(me->def->type),
	   9384                          me->def->alias_count,
	   9385                          obj_info(me->owner),
	   9386                          obj_info(me->defined_class));
	(lldb) p *me
	(rb_method_entry_t) $0 = {
	  flags = 24602
	  defined_class = 4311488400
	  def = 0x0000000000000000
	  called_id = 3057
	  owner = 4311488400
	}
	(lldb) bt
	* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	  * frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
	    frame #1: 0x00000001000b7cbf miniruby`obj_info(obj=4311487880) + 95 at gc.c:9423
	    frame #2: 0x00000001000c16a8 miniruby`newobj_init(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1, objspace=0x00000001007ee280, obj=4311487880) + 424 at gc.c:1887
	    frame #3: 0x00000001000b4529 miniruby`newobj_of(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1) + 217 at gc.c:1970
	    frame #4: 0x00000001000b46ab miniruby`rb_imemo_new(type=imemo_ment, v1=0, v2=3057, v3=4311488400, v0=4311488400) + 75 at gc.c:2017
	    frame #5: 0x00000001002773b4 miniruby`rb_method_entry_alloc(called_id=3057, owner=4311488400, defined_class=4311488400, def=0x0000000000000000) + 52 at vm_method.c:368
	    frame #6: 0x0000000100277307 miniruby`rb_method_entry_create(called_id=3057, klass=4311488400, visi=METHOD_VISI_PRIVATE, def=0x0000000000000000) + 71 at vm_method.c:389
	    frame #7: 0x00000001002784c7 miniruby`rb_method_entry_make(klass=4311488400, mid=3057, defined_class=4311488400, visi=METHOD_VISI_PRIVATE, type=VM_METHOD_TYPE_CFUNC, def=0x0000000000000000, original_id=3057, opts=0x00007fff5fbfd9e8) + 1207 at vm_method.c:594
	    frame #8: 0x00000001002770f9 miniruby`rb_add_method(klass=4311488400, mid=3057, type=VM_METHOD_TYPE_CFUNC, opts=0x00007fff5fbfd9e8, visi=METHOD_VISI_PRIVATE) + 73 at vm_method.c:650
	    frame #9: 0x000000010027708a miniruby`rb_add_method_cfunc(klass=4311488400, mid=3057, func=(miniruby`rb_obj_dummy at object.c:1125), argc=0, visi=METHOD_VISI_PRIVATE) + 138 at vm_method.c:137
	    frame #10: 0x00000001000391e4 miniruby`rb_define_private_method(klass=4311488400, name="initialize", func=(miniruby`rb_obj_dummy at object.c:1125), argc=0) + 68 at class.c:1529
	    frame #11: 0x000000010013f5bf miniruby`InitVM_Object + 47 at object.c:3905
	    frame #12: 0x0000000100142ffd miniruby`Init_Object + 61 at object.c:4122
	    frame #13: 0x00000001000d4edd miniruby`rb_call_inits + 29 at inits.c:23
	    frame #14: 0x000000010009fe66 miniruby`ruby_setup + 198 at eval.c:61
	    frame #15: 0x000000010009febd miniruby`ruby_init + 13 at eval.c:78
	    frame #16: 0x0000000100000a4d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
	    frame #17: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized local variable

	This imemo_name is used uninitialized because the switch
	above does not cover all possible imemo types.

	(lldb) run
	Process 26068 launched: './miniruby' (x86_64)
	Process 26068 stopped
	* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
	    frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
	libsystem_c.dylib`strlen:
	->  0x7fff8a402132 <+18>: pcmpeqb (%rdi), %xmm0
	    0x7fff8a402136 <+22>: pmovmskb %xmm0, %esi
	    0x7fff8a40213a <+26>: andq   $0xf, %rcx
	    0x7fff8a40213e <+30>: orq    $-0x1, %rax
	(lldb) bt
	* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
	  * frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
	    frame #1: 0x00000001001f1531 miniruby`BSD_vfprintf(fp=0x00007fff5fbfc9e0, fmt0="%s %s", ap=0x00007fff5fbfcbf0) + 5873 at vsnprintf.c:1026
	    frame #2: 0x00000001001ef213 miniruby`ruby_do_vsnprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s", ap=0x00007fff5fbfcbf0) + 131 at sprintf.c:1285
	    frame #3: 0x00000001001ef3ea miniruby`ruby_snprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s") + 426 at sprintf.c:1300
	    frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
	    frame #5: 0x00000001000b7bff miniruby`obj_info(obj=4310983760) + 95 at gc.c:9428
	    frame #6: 0x00000001000c1658 miniruby`newobj_init(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1, objspace=0x00000001007ee280, obj=4310983760) + 424 at gc.c:1887
	    frame #7: 0x00000001000b4469 miniruby`newobj_of(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1) + 217 at gc.c:1970
	    frame #8: 0x00000001000b45eb miniruby`rb_imemo_new(type=imemo_ast, v1=0, v2=4303040512, v3=4310983800, v0=0) + 75 at gc.c:2017
	    frame #9: 0x000000010011daed miniruby`rb_ast_new + 61 at node.c:1146
	    frame #10: 0x0000000100160e15 miniruby`rb_parser_compile_file_path(vparser=4310984400, fname=4310984960, file=4310984080, start=1) + 53 at parse.y:5776
	    frame #11: 0x00000001001e18ea miniruby`load_file_internal(argp_v=140734799795024) + 1834 at ruby.c:1907
	    frame #12: 0x00000001000a1bb5 miniruby`rb_ensure(b_proc=(miniruby`load_file_internal at ruby.c:1795), data1=140734799795024, e_proc=(miniruby`restore_load_file at ruby.c:2007), data2=140734799795024) + 245 at eval.c:1037
	    frame #13: 0x00000001001df4a4 miniruby`load_file(parser=4310984400, fname=4310984960, f=4310984080, script=1, opt=0x00007fff5fbfda28) + 100 at ruby.c:2026
	    frame #14: 0x00000001001e084e miniruby`process_options(argc=0, argv=0x00007fff5fbfdc00, opt=0x00007fff5fbfda28) + 3454 at ruby.c:1682
	    frame #15: 0x00000001001dfaae miniruby`ruby_process_options(argc=2, argv=0x00007fff5fbfdbf0) + 238 at ruby.c:2257
	    frame #16: 0x000000010009ff43 miniruby`ruby_options(argc=2, argv=0x00007fff5fbfdbf0) + 211 at eval.c:105
	    frame #17: 0x0000000100000989 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 105 at main.c:42
	    frame #18: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb) up 4
	frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
	   9373 #undef IMEMO_NAME
	   9374               default: UNREACHABLE;
	   9375             }
	-> 9376             snprintf(buff, buff_size, "%s %s", buff, imemo_name);
	   9377
	   9378             switch (imemo_type(obj)) {
	   9379               case imemo_ment: {
	(lldb) p imemo_name
	(const char *) $0 = 0xffffffffffffffff
	(lldb) p imemo_type(obj)
	(imemo_type) $1 = imemo_ast
	(lldb)

	fix SEGV inspecting already freed objects

	obj_info() assumes the given object is alive.  Passing freed
	objects to it results in SEGV.

	(lldb) run
	Process 29718 launched: './miniruby' (x86_64)
	Process 29718 stopped
	* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	    frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
	   266      }
	   267      else {
	   268          VM_ASSERT(RB_TYPE_P(pathobj, T_ARRAY));
	-> 269          return RARRAY_AREF(pathobj, PATHOBJ_PATH);
	   270      }
	   271  }
	   272
	(lldb) bt
	* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	  * frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
	    frame #1: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x000000010af34a20) + 32 at iseq.c:723
	    frame #2: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, iseq=0x000000010af34a20) + 69 at gc.c:9274
	    frame #3: 0x000000010009e45a miniruby`rb_raw_obj_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, obj=4478683680) + 2191 at gc.c:9397
	    frame #4: 0x000000010009e4d5 miniruby`obj_info(obj=4478683680) + 98 at gc.c:9429
	    frame #5: 0x0000000100091ae3 miniruby`gc_page_sweep(objspace=0x00000001007d3280, heap=0x00000001007d32a0, sweep_page=0x000000010ae07bc0) + 622 at gc.c:3529
	    frame #6: 0x000000010009206a miniruby`gc_sweep_step(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 188 at gc.c:3705
	    frame #7: 0x0000000100092254 miniruby`gc_sweep_continue(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 133 at gc.c:3772
	    frame #8: 0x000000010008d7f9 miniruby`heap_prepare(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 48 at gc.c:1746
	    frame #9: 0x000000010008d8a1 miniruby`heap_get_freeobj_from_next_freepage(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 37 at gc.c:1769
	    frame #10: 0x000000010008d98d miniruby`heap_get_freeobj(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 83 at gc.c:1803
	    frame #11: 0x000000010008dcb0 miniruby`newobj_slowpath(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280, wb_protected=1) + 220 at gc.c:1930
	    frame #12: 0x000000010008dd6c miniruby`newobj_slowpath_wb_protected(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280) + 76 at gc.c:1942
	    frame #13: 0x000000010008dea1 miniruby`newobj_of(klass=4334386280, flags=5, v1=0, v2=0, v3=0, wb_protected=1) + 221 at gc.c:1974
	    frame #14: 0x000000010008df39 miniruby`rb_wb_protected_newobj_of(klass=4334386280, flags=5) + 54 at gc.c:1990
	    frame #15: 0x0000000100195f7c miniruby`str_alloc(klass=4334386280) + 29 at string.c:692
	    frame #16: 0x0000000100195fe9 miniruby`str_new0(klass=4334386280, ptr="gitm", len=4, termlen=1) + 73 at string.c:714
	    frame #17: 0x000000010019633e miniruby`rb_enc_str_new(ptr="gitm", len=4, enc=0x00000001025d50a0) + 81 at string.c:766
	    frame #18: 0x000000010010a80a miniruby`parser_str_new(p="gitm", n=4, enc=0x00000001025d50a0, func=66, enc0=0x00000001025d50a0) + 50 at parse.y:5817
	    frame #19: 0x000000010010ce1a miniruby`parser_parse_string(parser=0x00000001042ac5c0, quote=0x000000010460c028) + 795 at parse.y:6675
	    frame #20: 0x00000001001120bd miniruby`parser_yylex(parser=0x00000001042ac5c0) + 159 at parse.y:8281
	    frame #21: 0x0000000100115068 miniruby`yylex(lval=0x00007fff5fbf9948, yylloc=0x00007fff5fbf9ab0, parser=0x00000001042ac5c0) + 55 at parse.y:8931
	    frame #22: 0x00000001000fc79f miniruby`ruby_yyparse(parser=0x00000001042ac5c0) + 1198 at parse.c:5798
	    frame #23: 0x0000000100109f5a miniruby`yycompile0(arg=4364879296) + 317 at parse.y:5595
	    frame #24: 0x0000000100214ef0 miniruby`rb_suppress_tracing(func=(miniruby`yycompile0 at parse.y:5565), arg=4364879296) + 349 at vm_trace.c:397
	    frame #25: 0x000000010010a1df miniruby`yycompile(parser=0x00000001042ac5c0, fname=4443743440, line=1) + 126 at parse.y:5637
	    frame #26: 0x000000010010a4c1 miniruby`parser_compile_string(vparser=4443743480, fname=4443743440, s=4443743520, line=1) + 191 at parse.y:5706
	    frame #27: 0x000000010010a5b7 miniruby`rb_parser_compile_string_path(vparser=4443743480, f=4443743440, s=4443743520, line=1) + 58 at parse.y:5730
	    frame #28: 0x0000000100206025 miniruby`eval_make_iseq(src=4443743520, fname=4443743440, line=1, bind=0x0000000000000000, base_block=0x00007fff5fbfb370) + 266 at vm_eval.c:1274
	    frame #29: 0x0000000100206153 miniruby`eval_string_with_cref(self=4334412520, src=4443743520, cref=0x0000000000000000, file=52, line=1) + 197 at vm_eval.c:1307
	    frame #30: 0x0000000100206389 miniruby`rb_f_eval(argc=1, argv=0x0000000102400eb8, self=4334412520) + 219 at vm_eval.c:1382
	    frame #31: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_eval at vm_eval.c:1364), recv=4334412520, argc=1, argv=0x0000000102400eb8) + 47 at vm_insnhelper.c:1723
	    frame #32: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 386 at vm_insnhelper.c:1918
	    frame #33: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 149 at vm_insnhelper.c:1934
	    frame #34: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #35: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #36: 0x00000001002093f8 miniruby`invoke_block(ec=0x00000001007d3548, iseq=0x000000010252d7f0, self=4334412520, captured=0x0000000102500df8, cref=0x0000000000000000, type=572653569, opt_pc=0) + 224 at vm.c:988
	    frame #37: 0x0000000100209766 miniruby`invoke_iseq_block_from_c(ec=0x00000001007d3548, captured=0x0000000102500df8, self=4334412520, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0) + 389 at vm.c:1040
	    frame #38: 0x0000000100209824 miniruby`invoke_block_from_c_bh(ec=0x00000001007d3548, block_handler=4333768185, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0, force_blockarg=0) + 138 at vm.c:1058
	    frame #39: 0x00000001002099d0 miniruby`vm_yield(ec=0x00000001007d3548, argc=0, argv=0x0000000000000000) + 69 at vm.c:1103
	    frame #40: 0x0000000100205623 miniruby`rb_yield_0(argc=0, argv=0x0000000000000000) + 40 at vm_eval.c:970
	    frame #41: 0x0000000100205964 miniruby`loop_i + 19 at vm_eval.c:1049
	    frame #42: 0x000000010007db07 miniruby`rb_rescue2(b_proc=(miniruby`loop_i at vm_eval.c:1047), data1=0, r_proc=(miniruby`loop_stop at vm_eval.c:1056), data2=0) + 369 at eval.c:896
	    frame #43: 0x0000000100205a2e miniruby`rb_f_loop(self=4334412520) + 121 at vm_eval.c:1100
	    frame #44: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_f_loop at vm_eval.c:1098), recv=4334412520, argc=0, argv=0x0000000102400e80) + 41 at vm_insnhelper.c:1729
	    frame #45: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 386 at vm_insnhelper.c:1918
	    frame #46: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 149 at vm_insnhelper.c:1934
	    frame #47: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 239 at vm_insnhelper.c:2232
	    frame #48: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 253 at vm_insnhelper.c:2366
	    frame #49: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 59 at vm_insnhelper.c:2398
	    frame #50: 0x00000001001fab2f miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 7480 at insns.def:850
	    frame #51: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #52: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x000000010252dd90) + 52 at vm.c:2019
	    frame #53: 0x000000010007c768 miniruby`ruby_exec_internal(n=0x000000010252dd90) + 297 at eval.c:246
	    frame #54: 0x000000010007c88e miniruby`ruby_exec_node(n=0x000000010252dd90) + 36 at eval.c:310
	    frame #55: 0x000000010007c861 miniruby`ruby_run_node(n=0x000000010252dd90) + 62 at eval.c:302
	    frame #56: 0x000000010000138d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
	    frame #57: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb) p ((struct RVALUE*)pathobj)->as.basic
	(RBasic) $0 = (flags = 0, klass = 4478683600)
	(lldb)

	fix SEGV inspecting uninitialized objects

	obj_info() assumes the given object is alive.  OTOH
	gc_writebarrier_incremental is called before or in middle of
	object initialization.  Can casue SEGV.

	(lldb) run
	Process 48188 launched: './miniruby' (x86_64)
	Process 48188 stopped
	* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
	    frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
	   2069 static inline const VALUE *
	   2070 rb_array_const_ptr(VALUE a)
	   2071 {
	-> 2072     return FIX_CONST_VALUE_PTR((RBASIC(a)->flags & RARRAY_EMBED_FLAG) ?
	   2073         RARRAY(a)->as.ary : RARRAY(a)->as.heap.ptr);
	   2074 }
	   2075
	(lldb) bt
	* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
	  * frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
	    frame #1: 0x00000001000bfaab miniruby`pathobj_path(pathobj=5251291222225483145) + 70 at vm_core.h:269
	    frame #2: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x00000001025b71a8) + 32 at iseq.c:723
	    frame #3: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, iseq=0x00000001025b71a8) + 69 at gc.c:9274
	    frame #4: 0x000000010009e1d5 miniruby`rb_raw_obj_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, obj=4334514520) + 1546 at gc.c:9351
	    frame #5: 0x000000010009e4d5 miniruby`obj_info(obj=4334514520) + 98 at gc.c:9429
	    frame #6: 0x0000000100096658 miniruby`gc_writebarrier_incremental(a=4334514520, b=4334514600, objspace=0x00000001007d3280) + 61 at gc.c:5963
	    frame #7: 0x00000001000968ca miniruby`rb_gc_writebarrier(a=4334514520, b=4334514600) + 127 at gc.c:6009
	    frame #8: 0x00000001001eabe0 miniruby`rb_obj_written(a=4334514520, oldv=52, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 72 at ruby.h:1472
	    frame #9: 0x00000001001eac2c miniruby`rb_obj_write(a=4334514520, slot=0x000000010259ff10, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 70 at ruby.h:1489
	    frame #10: 0x0000000100208b6f miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x0000000102500338, block_type=block_type_ifunc, is_from_method='\0', is_lambda='\x01') + 137 at vm.c:821
	    frame #11: 0x0000000100208e5c miniruby`rb_vm_make_proc_lambda(ec=0x00000001007d3548, captured=0x0000000102500338, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
	    frame #12: 0x000000010011f08e miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
	    frame #13: 0x000000010011f110 miniruby`rb_block_lambda + 27 at proc.c:808
	    frame #14: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000000000000) + 41 at vm_insnhelper.c:1729
	    frame #15: 0x00000001002033de miniruby`vm_call0_cfunc_with_frame(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 370 at vm_eval.c:85
	    frame #16: 0x00000001002034d9 miniruby`vm_call0_cfunc(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 59 at vm_eval.c:100
	    frame #17: 0x000000010020368f miniruby`vm_call0_body(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 436 at vm_eval.c:131
	    frame #18: 0x000000010020326a miniruby`vm_call0(ec=0x00000001007d3548, recv=4310991600, id=2993, argc=0, argv=0x0000000000000000, me=0x0000000100f48110) + 142 at vm_eval.c:58
	    frame #19: 0x0000000100203c60 miniruby`rb_call0(ec=0x00000001007d3548, recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL, self=4334514640) + 166 at vm_eval.c:296
	    frame #20: 0x0000000100204827 miniruby`rb_call(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL) + 84 at vm_eval.c:589
	    frame #21: 0x000000010020518b miniruby`rb_funcallv(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000) + 52 at vm_eval.c:815
	    frame #22: 0x000000010012242e miniruby`mlambda(method=0) + 45 at proc.c:2661
	    frame #23: 0x0000000100205bac miniruby`rb_iterate0(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, ifunc=0x00000001025b71a8, ec=0x00000001007d3548) + 380 at vm_eval.c:1134
	    frame #24: 0x0000000100205d16 miniruby`rb_iterate(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, bl_proc=(miniruby`bmcall at proc.c:2666), data2=4334514640) + 88 at vm_eval.c:1166
	    frame #25: 0x00000001001224c7 miniruby`method_to_proc(method=4334514640) + 43 at proc.c:2701
	    frame #26: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`method_to_proc at proc.c:2688), recv=4334514640, argc=0, argv=0x0000000102400568) + 41 at vm_insnhelper.c:1729
	    frame #27: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 386 at vm_insnhelper.c:1918
	    frame #28: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 149 at vm_insnhelper.c:1934
	    frame #29: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 239 at vm_insnhelper.c:2232
	    frame #30: 0x00000001001f49a4 miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 117 at vm_insnhelper.c:2355
	    frame #31: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 59 at vm_insnhelper.c:2398
	    frame #32: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #33: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #34: 0x000000010020c3d1 miniruby`rb_iseq_eval(iseq=0x00000001007f8270) + 52 at vm.c:2008
	    frame #35: 0x00000001000caa4a miniruby`rb_load_internal0(ec=0x00000001007d3548, fname=4310799960, wrap=0) + 631 at load.c:611
	    frame #36: 0x00000001000cab36 miniruby`rb_load_internal(fname=4310799960, wrap=0) + 46 at load.c:642
	    frame #37: 0x00000001000cae1d miniruby`rb_f_load(argc=1, argv=0x00000001024004b8) + 217 at load.c:710
	    frame #38: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_load at load.c:695), recv=4311327440, argc=1, argv=0x00000001024004b8) + 47 at vm_insnhelper.c:1723
	    frame #39: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 386 at vm_insnhelper.c:1918
	    frame #40: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 149 at vm_insnhelper.c:1934
	    frame #41: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 239 at vm_insnhelper.c:2232
	    frame #42: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 253 at vm_insnhelper.c:2366
	    frame #43: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 59 at vm_insnhelper.c:2398
	    frame #44: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #45: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #46: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x0000000100f21240) + 52 at vm.c:2019
	    frame #47: 0x000000010007c774 miniruby`ruby_exec_internal(n=0x0000000100f21240) + 297 at eval.c:246
	    frame #48: 0x000000010007c89a miniruby`ruby_exec_node(n=0x0000000100f21240) + 36 at eval.c:310
	    frame #49: 0x000000010007c86d miniruby`ruby_run_node(n=0x0000000100f21240) + 62 at eval.c:302
	    frame #50: 0x0000000100001399 miniruby`main(argc=9, argv=0x00007fff5fbfdae0) + 113 at main.c:42
	    frame #51: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@62850 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	fix SEGV touching uninitialized memory

	This function can be called from Init_VM().
	No assumption can be made about object internals.

	(lldb) run
	Process 15734 launched: './miniruby' (x86_64)
	Process 15734 stopped
	* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
	    frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
	   9270 static void
	   9271 rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
	   9272 {
	-> 9273     if (iseq->body->location.label) {
	   9274         VALUE path = rb_iseq_path(iseq);
	   9275         snprintf(buff, buff_size, "%s %s@%s:%d", buff,
	   9276                  RSTRING_PTR(iseq->body->location.label),
	(lldb) p *iseq
	(rb_iseq_t) $0 = {
	  flags = 28698
	  reserved1 = 0
	  body = 0x0000000000000000
	  aux = {
	    compile_data = 0x0000000000000000
	    loader = (obj = 0, index = 0)
	    trace_events = 0
	  }
	}
	(lldb) bt
	* thread #1: tid = 0x1441d4, 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x50)
	  * frame #0: 0x00000001000bdfcb miniruby`rb_raw_iseq_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, iseq=0x0000000100f61f48) + 27 at gc.c:9273
	    frame #1: 0x00000001000bde72 miniruby`rb_raw_obj_info(buff="0x0000000100f61f48 [0    ] T_IMEMO iseq", buff_size=256, obj=4311097160) + 2786 at gc.c:9396
	    frame #2: 0x00000001000b7c5f miniruby`obj_info(obj=4311097160) + 95 at gc.c:9428
	    frame #3: 0x00000001000c16a8 miniruby`newobj_init(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007ee280, obj=4311097160) + 424 at gc.c:1887
	    frame #4: 0x00000001000b44c9 miniruby`newobj_of(klass=0, flags=28698, v1=0, v2=0, v3=0, wb_protected=1) + 217 at gc.c:1970
	    frame #5: 0x00000001000b464b miniruby`rb_imemo_new(type=imemo_iseq, v1=0, v2=0, v3=0, v0=0) + 75 at gc.c:2017
	    frame #6: 0x00000001000fd914 miniruby`iseq_imemo_alloc + 36 at iseq.h:156
	    frame #7: 0x00000001000f6e1d miniruby`iseq_alloc + 13 at iseq.c:211
	    frame #8: 0x00000001000f6bf8 miniruby`rb_iseq_new_with_opt(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, first_lineno=1, parent=0x0000000000000000, type=ISEQ_TYPE_TOP, option=0x0000000100335c30) + 56 at iseq.c:519
	    frame #9: 0x00000001000f6bb6 miniruby`rb_iseq_new(node=0x0000000000000000, name=4311097200, path=4311097200, realpath=8, parent=0x0000000000000000, type=ISEQ_TYPE_TOP) + 86 at iseq.c:480
	    frame #10: 0x0000000100284bb0 miniruby`Init_VM + 1040 at vm.c:3022
	    frame #11: 0x00000001000d4f7d miniruby`rb_call_inits + 189 at inits.c:55
	    frame #12: 0x000000010009fe06 miniruby`ruby_setup + 198 at eval.c:61
	    frame #13: 0x000000010009fe5d miniruby`ruby_init + 13 at eval.c:78
	    frame #14: 0x00000001000009ed miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
	    frame #15: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized memory

	This function can be called from rb_data_typed_object_zalloc().
	No assumption can be made about object internals.

	(lldb) run
	Process 22135 launched: './miniruby' (x86_64)
	Process 22135 stopped
	* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
	    frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
	   1361         break;
	   1362     }
	   1363 #endif
	-> 1364     return block->type;
	   1365 }
	   1366
	   1367 static inline void
	(lldb) bt
	* thread #1: tid = 0x14a3af, 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x18)
	  * frame #0: 0x000000010008ac8a miniruby`vm_block_type(block=0x0000000000000000) + 12 at vm_core.h:1364
	    frame #1: 0x000000010008acdb miniruby`vm_block_iseq(block=0x0000000000000000) + 24 at vm_core.h:1399
	    frame #2: 0x000000010008acc1 miniruby`vm_proc_iseq(procval=4310866360) + 32 at vm_core.h:1387
	    frame #3: 0x000000010009cbed miniruby`rb_raw_obj_info(buff="0x0000000100f299b8 [0    ] proc (Proc)", buff_size=256, obj=4310866360) + 1513 at gc.c:9349
	    frame #4: 0x000000010009cf01 miniruby`obj_info(obj=4310866360) + 98 at gc.c:9428
	    frame #5: 0x000000010008ca1b miniruby`newobj_init(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32, objspace=0x00000001007cf280, obj=4310866360) + 338 at gc.c:1887
	    frame #6: 0x000000010008cce5 miniruby`newobj_of(klass=4311027960, flags=12, v1=4298186080, v2=1, v3=0, wb_protected=32) + 171 at gc.c:1970
	    frame #7: 0x000000010008d01d miniruby`rb_data_typed_object_wrap(klass=4311027960, datap=0x0000000000000000, type=0x0000000100311d60) + 133 at gc.c:2062
	    frame #8: 0x000000010008d04e miniruby`rb_data_typed_object_zalloc(klass=4311027960, size=40, type=0x0000000100311d60) + 42 at gc.c:2073
	    frame #9: 0x000000010011b459 miniruby`rb_proc_alloc(klass=4311027960) + 36 at proc.c:113
	    frame #10: 0x0000000100204d8e miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x00000001025003f8, block_type=block_type_iseq, is_from_method='\0', is_lambda='\x01') + 44 at vm.c:814
	    frame #11: 0x00000001002050d8 miniruby`rb_vm_make_proc_lambda(ec=0x00000001007cf548, captured=0x00000001025003f8, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
	    frame #12: 0x000000010011c0d2 miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
	    frame #13: 0x000000010011c154 miniruby`rb_block_lambda + 27 at proc.c:808
	    frame #14: 0x00000001001ee7e3 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000102400480) + 41 at vm_insnhelper.c:1729
	    frame #15: 0x00000001001ef2c3 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 386 at vm_insnhelper.c:1918
	    frame #16: 0x00000001001ef412 miniruby`vm_call_cfunc(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 149 at vm_insnhelper.c:1934
	    frame #17: 0x00000001001f0655 miniruby`vm_call_method_each_type(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 239 at vm_insnhelper.c:2232
	    frame #18: 0x00000001001f0ce0 miniruby`vm_call_method(ec=0x00000001007cf548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 117 at vm_insnhelper.c:2355
	    frame #19: 0x00000001001f0eb6 miniruby`vm_call_general(ec=0x00000001007cf548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd4d0, ci=0x0000000102537be0, cc=0x000000010253e0f0) + 59 at vm_insnhelper.c:2398
	    frame #20: 0x00000001001f6e61 miniruby`vm_exec_core(ec=0x00000001007cf548, initial=0) + 7480 at insns.def:850
	    frame #21: 0x0000000100207995 miniruby`vm_exec(ec=0x00000001007cf548) + 230 at vm.c:1771
	    frame #22: 0x0000000100208647 miniruby`rb_iseq_eval_main(iseq=0x0000000100f29fd0) + 52 at vm.c:2019
	    frame #23: 0x000000010007b750 miniruby`ruby_exec_internal(n=0x0000000100f29fd0) + 297 at eval.c:246
	    frame #24: 0x000000010007b876 miniruby`ruby_exec_node(n=0x0000000100f29fd0) + 36 at eval.c:310
	    frame #25: 0x000000010007b849 miniruby`ruby_run_node(n=0x0000000100f29fd0) + 62 at eval.c:302
	    frame #26: 0x0000000100000c05 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
	    frame #27: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	check an existence of block.

	* gc.c (rb_raw_obj_info): check block before using it.

	* vm_core.h (vm_block_iseq): r61565 introduced NULL check but this
	  check is only needed by `rb_raw_obj_info()` and it is called at GC
	  debug mode. Above fix for `rb_raw_obj_info()` solves this problem and
	  NULL check should not be needed any more.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@62864 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	fix SEGV touching uninitialized memory

	This function can be called from boot_defclass().
	No assumption can be made about object internals.

	(lldb) run
	Process 2386 launched: './miniruby' (x86_64)
	Process 2386 stopped
	* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
	    frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
	   318  VALUE
	   319  rb_class_path_cached(VALUE klass)
	   320  {
	-> 321      st_table *ivtbl = RCLASS_IV_TBL(klass);
	   322      st_data_t n;
	   323
	   324      if (!ivtbl) return Qnil;
	(lldb) bt
	* thread #1: tid = 0x13f3b6, 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x8)
	  * frame #0: 0x00000001001e0b26 miniruby`rb_class_path_cached(klass=4311373720) + 20 at variable.c:321
	    frame #1: 0x000000010009cbd0 miniruby`rb_raw_obj_info(buff="0x0000000100fa5798 [2    ] T_CLASS", buff_size=256, obj=4311373720) + 1393 at gc.c:9341
	    frame #2: 0x000000010009cf16 miniruby`obj_info(obj=4311373720) + 98 at gc.c:9423
	    frame #3: 0x000000010008ca87 miniruby`newobj_init(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x00000001007cf280, obj=4311373720) + 338 at gc.c:1887
	    frame #4: 0x000000010008cd51 miniruby`newobj_of(klass=0, flags=66, v1=0, v2=0, v3=0, wb_protected=1) + 171 at gc.c:1970
	    frame #5: 0x000000010008ce1b miniruby`rb_wb_protected_newobj_of(klass=0, flags=66) + 54 at gc.c:1990
	    frame #6: 0x0000000100027563 miniruby`class_alloc(flags=2, klass=0) + 46 at class.c:165
	    frame #7: 0x000000010002761a miniruby`rb_class_boot(super=0) + 35 at class.c:203
	    frame #8: 0x0000000100028612 miniruby`boot_defclass(name="BasicObject", super=0) + 28 at class.c:537
	    frame #9: 0x000000010002868b miniruby`Init_class_hierarchy + 26 at class.c:548
	    frame #10: 0x00000001000efe69 miniruby`InitVM_Object + 9 at object.c:3892
	    frame #11: 0x00000001000f138e miniruby`Init_Object + 57 at object.c:4122
	    frame #12: 0x00000001000a59bd miniruby`rb_call_inits + 29 at inits.c:23
	    frame #13: 0x000000010007af30 miniruby`ruby_setup + 229 at eval.c:61
	    frame #14: 0x000000010007af7e miniruby`ruby_init + 13 at eval.c:78
	    frame #15: 0x0000000100000c58 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 88 at main.c:41
	    frame #16: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized memory

	This function can be called from InitVM_Object().
	No assumption can be made about object internals.

	(lldb) run
	Process 10675 launched: './miniruby' (x86_64)
	Process 10675 stopped
	* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	    frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
	   9380                 const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
	   9381                 snprintf(buff, buff_size, "%s (called_id: %s, type: %s, alias: %d, owner: %s, defined_class: %s)", buff,
	   9382                          rb_id2name(me->called_id),
	-> 9383                          method_type_name(me->def->type),
	   9384                          me->def->alias_count,
	   9385                          obj_info(me->owner),
	   9386                          obj_info(me->defined_class));
	(lldb) p *me
	(rb_method_entry_t) $0 = {
	  flags = 24602
	  defined_class = 4311488400
	  def = 0x0000000000000000
	  called_id = 3057
	  owner = 4311488400
	}
	(lldb) bt
	* thread #1: tid = 0x14252c, 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	  * frame #0: 0x00000001000bdda9 miniruby`rb_raw_obj_info(buff="0x0000000100fc1588 [0    ] T_IMEMO ment", buff_size=256, obj=4311487880) + 2489 at gc.c:9383
	    frame #1: 0x00000001000b7cbf miniruby`obj_info(obj=4311487880) + 95 at gc.c:9423
	    frame #2: 0x00000001000c16a8 miniruby`newobj_init(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1, objspace=0x00000001007ee280, obj=4311487880) + 424 at gc.c:1887
	    frame #3: 0x00000001000b4529 miniruby`newobj_of(klass=4311488400, flags=24602, v1=0, v2=3057, v3=4311488400, wb_protected=1) + 217 at gc.c:1970
	    frame #4: 0x00000001000b46ab miniruby`rb_imemo_new(type=imemo_ment, v1=0, v2=3057, v3=4311488400, v0=4311488400) + 75 at gc.c:2017
	    frame #5: 0x00000001002773b4 miniruby`rb_method_entry_alloc(called_id=3057, owner=4311488400, defined_class=4311488400, def=0x0000000000000000) + 52 at vm_method.c:368
	    frame #6: 0x0000000100277307 miniruby`rb_method_entry_create(called_id=3057, klass=4311488400, visi=METHOD_VISI_PRIVATE, def=0x0000000000000000) + 71 at vm_method.c:389
	    frame #7: 0x00000001002784c7 miniruby`rb_method_entry_make(klass=4311488400, mid=3057, defined_class=4311488400, visi=METHOD_VISI_PRIVATE, type=VM_METHOD_TYPE_CFUNC, def=0x0000000000000000, original_id=3057, opts=0x00007fff5fbfd9e8) + 1207 at vm_method.c:594
	    frame #8: 0x00000001002770f9 miniruby`rb_add_method(klass=4311488400, mid=3057, type=VM_METHOD_TYPE_CFUNC, opts=0x00007fff5fbfd9e8, visi=METHOD_VISI_PRIVATE) + 73 at vm_method.c:650
	    frame #9: 0x000000010027708a miniruby`rb_add_method_cfunc(klass=4311488400, mid=3057, func=(miniruby`rb_obj_dummy at object.c:1125), argc=0, visi=METHOD_VISI_PRIVATE) + 138 at vm_method.c:137
	    frame #10: 0x00000001000391e4 miniruby`rb_define_private_method(klass=4311488400, name="initialize", func=(miniruby`rb_obj_dummy at object.c:1125), argc=0) + 68 at class.c:1529
	    frame #11: 0x000000010013f5bf miniruby`InitVM_Object + 47 at object.c:3905
	    frame #12: 0x0000000100142ffd miniruby`Init_Object + 61 at object.c:4122
	    frame #13: 0x00000001000d4edd miniruby`rb_call_inits + 29 at inits.c:23
	    frame #14: 0x000000010009fe66 miniruby`ruby_setup + 198 at eval.c:61
	    frame #15: 0x000000010009febd miniruby`ruby_init + 13 at eval.c:78
	    frame #16: 0x0000000100000a4d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 93 at main.c:41
	    frame #17: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

	fix SEGV touching uninitialized local variable

	This imemo_name is used uninitialized because the switch
	above does not cover all possible imemo types.

	(lldb) run
	Process 26068 launched: './miniruby' (x86_64)
	Process 26068 stopped
	* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
	    frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
	libsystem_c.dylib`strlen:
	->  0x7fff8a402132 <+18>: pcmpeqb (%rdi), %xmm0
	    0x7fff8a402136 <+22>: pmovmskb %xmm0, %esi
	    0x7fff8a40213a <+26>: andq   $0xf, %rcx
	    0x7fff8a40213e <+30>: orq    $-0x1, %rax
	(lldb) bt
	* thread #1: tid = 0x14ba96, 0x00007fff8a402132 libsystem_c.dylib`strlen + 18, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff0)
	  * frame #0: 0x00007fff8a402132 libsystem_c.dylib`strlen + 18
	    frame #1: 0x00000001001f1531 miniruby`BSD_vfprintf(fp=0x00007fff5fbfc9e0, fmt0="%s %s", ap=0x00007fff5fbfcbf0) + 5873 at vsnprintf.c:1026
	    frame #2: 0x00000001001ef213 miniruby`ruby_do_vsnprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s", ap=0x00007fff5fbfcbf0) + 131 at sprintf.c:1285
	    frame #3: 0x00000001001ef3ea miniruby`ruby_snprintf(str="0x0000000100f46450 [0    ] T_IMEMO", n=256, fmt="%s %s") + 426 at sprintf.c:1300
	    frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
	    frame #5: 0x00000001000b7bff miniruby`obj_info(obj=4310983760) + 95 at gc.c:9428
	    frame #6: 0x00000001000c1658 miniruby`newobj_init(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1, objspace=0x00000001007ee280, obj=4310983760) + 424 at gc.c:1887
	    frame #7: 0x00000001000b4469 miniruby`newobj_of(klass=0, flags=36890, v1=0, v2=4303040512, v3=4310983800, wb_protected=1) + 217 at gc.c:1970
	    frame #8: 0x00000001000b45eb miniruby`rb_imemo_new(type=imemo_ast, v1=0, v2=4303040512, v3=4310983800, v0=0) + 75 at gc.c:2017
	    frame #9: 0x000000010011daed miniruby`rb_ast_new + 61 at node.c:1146
	    frame #10: 0x0000000100160e15 miniruby`rb_parser_compile_file_path(vparser=4310984400, fname=4310984960, file=4310984080, start=1) + 53 at parse.y:5776
	    frame #11: 0x00000001001e18ea miniruby`load_file_internal(argp_v=140734799795024) + 1834 at ruby.c:1907
	    frame #12: 0x00000001000a1bb5 miniruby`rb_ensure(b_proc=(miniruby`load_file_internal at ruby.c:1795), data1=140734799795024, e_proc=(miniruby`restore_load_file at ruby.c:2007), data2=140734799795024) + 245 at eval.c:1037
	    frame #13: 0x00000001001df4a4 miniruby`load_file(parser=4310984400, fname=4310984960, f=4310984080, script=1, opt=0x00007fff5fbfda28) + 100 at ruby.c:2026
	    frame #14: 0x00000001001e084e miniruby`process_options(argc=0, argv=0x00007fff5fbfdc00, opt=0x00007fff5fbfda28) + 3454 at ruby.c:1682
	    frame #15: 0x00000001001dfaae miniruby`ruby_process_options(argc=2, argv=0x00007fff5fbfdbf0) + 238 at ruby.c:2257
	    frame #16: 0x000000010009ff43 miniruby`ruby_options(argc=2, argv=0x00007fff5fbfdbf0) + 211 at eval.c:105
	    frame #17: 0x0000000100000989 miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 105 at main.c:42
	    frame #18: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb) up 4
	frame #4: 0x00000001000bdc61 miniruby`rb_raw_obj_info(buff="0x0000000100f46450 [0    ] T_IMEMO", buff_size=256, obj=4310983760) + 2353 at gc.c:9376
	   9373 #undef IMEMO_NAME
	   9374               default: UNREACHABLE;
	   9375             }
	-> 9376             snprintf(buff, buff_size, "%s %s", buff, imemo_name);
	   9377
	   9378             switch (imemo_type(obj)) {
	   9379               case imemo_ment: {
	(lldb) p imemo_name
	(const char *) $0 = 0xffffffffffffffff
	(lldb) p imemo_type(obj)
	(imemo_type) $1 = imemo_ast
	(lldb)

	fix SEGV inspecting already freed objects

	obj_info() assumes the given object is alive.  Passing freed
	objects to it results in SEGV.

	(lldb) run
	Process 29718 launched: './miniruby' (x86_64)
	Process 29718 stopped
	* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	    frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
	   266      }
	   267      else {
	   268          VM_ASSERT(RB_TYPE_P(pathobj, T_ARRAY));
	-> 269          return RARRAY_AREF(pathobj, PATHOBJ_PATH);
	   270      }
	   271  }
	   272
	(lldb) bt
	* thread #1: tid = 0x3082c5, 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
	  * frame #0: 0x00000001000bfaab miniruby`pathobj_path(pathobj=4478683640) + 70 at vm_core.h:269
	    frame #1: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x000000010af34a20) + 32 at iseq.c:723
	    frame #2: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, iseq=0x000000010af34a20) + 69 at gc.c:9274
	    frame #3: 0x000000010009e45a miniruby`rb_raw_obj_info(buff="0x000000010af34a20 [1    ] T_IMEMO iseq", buff_size=256, obj=4478683680) + 2191 at gc.c:9397
	    frame #4: 0x000000010009e4d5 miniruby`obj_info(obj=4478683680) + 98 at gc.c:9429
	    frame #5: 0x0000000100091ae3 miniruby`gc_page_sweep(objspace=0x00000001007d3280, heap=0x00000001007d32a0, sweep_page=0x000000010ae07bc0) + 622 at gc.c:3529
	    frame #6: 0x000000010009206a miniruby`gc_sweep_step(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 188 at gc.c:3705
	    frame #7: 0x0000000100092254 miniruby`gc_sweep_continue(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 133 at gc.c:3772
	    frame #8: 0x000000010008d7f9 miniruby`heap_prepare(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 48 at gc.c:1746
	    frame #9: 0x000000010008d8a1 miniruby`heap_get_freeobj_from_next_freepage(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 37 at gc.c:1769
	    frame #10: 0x000000010008d98d miniruby`heap_get_freeobj(objspace=0x00000001007d3280, heap=0x00000001007d32a0) + 83 at gc.c:1803
	    frame #11: 0x000000010008dcb0 miniruby`newobj_slowpath(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280, wb_protected=1) + 220 at gc.c:1930
	    frame #12: 0x000000010008dd6c miniruby`newobj_slowpath_wb_protected(klass=4334386280, flags=5, v1=0, v2=0, v3=0, objspace=0x00000001007d3280) + 76 at gc.c:1942
	    frame #13: 0x000000010008dea1 miniruby`newobj_of(klass=4334386280, flags=5, v1=0, v2=0, v3=0, wb_protected=1) + 221 at gc.c:1974
	    frame #14: 0x000000010008df39 miniruby`rb_wb_protected_newobj_of(klass=4334386280, flags=5) + 54 at gc.c:1990
	    frame #15: 0x0000000100195f7c miniruby`str_alloc(klass=4334386280) + 29 at string.c:692
	    frame #16: 0x0000000100195fe9 miniruby`str_new0(klass=4334386280, ptr="gitm", len=4, termlen=1) + 73 at string.c:714
	    frame #17: 0x000000010019633e miniruby`rb_enc_str_new(ptr="gitm", len=4, enc=0x00000001025d50a0) + 81 at string.c:766
	    frame #18: 0x000000010010a80a miniruby`parser_str_new(p="gitm", n=4, enc=0x00000001025d50a0, func=66, enc0=0x00000001025d50a0) + 50 at parse.y:5817
	    frame #19: 0x000000010010ce1a miniruby`parser_parse_string(parser=0x00000001042ac5c0, quote=0x000000010460c028) + 795 at parse.y:6675
	    frame #20: 0x00000001001120bd miniruby`parser_yylex(parser=0x00000001042ac5c0) + 159 at parse.y:8281
	    frame #21: 0x0000000100115068 miniruby`yylex(lval=0x00007fff5fbf9948, yylloc=0x00007fff5fbf9ab0, parser=0x00000001042ac5c0) + 55 at parse.y:8931
	    frame #22: 0x00000001000fc79f miniruby`ruby_yyparse(parser=0x00000001042ac5c0) + 1198 at parse.c:5798
	    frame #23: 0x0000000100109f5a miniruby`yycompile0(arg=4364879296) + 317 at parse.y:5595
	    frame #24: 0x0000000100214ef0 miniruby`rb_suppress_tracing(func=(miniruby`yycompile0 at parse.y:5565), arg=4364879296) + 349 at vm_trace.c:397
	    frame #25: 0x000000010010a1df miniruby`yycompile(parser=0x00000001042ac5c0, fname=4443743440, line=1) + 126 at parse.y:5637
	    frame #26: 0x000000010010a4c1 miniruby`parser_compile_string(vparser=4443743480, fname=4443743440, s=4443743520, line=1) + 191 at parse.y:5706
	    frame #27: 0x000000010010a5b7 miniruby`rb_parser_compile_string_path(vparser=4443743480, f=4443743440, s=4443743520, line=1) + 58 at parse.y:5730
	    frame #28: 0x0000000100206025 miniruby`eval_make_iseq(src=4443743520, fname=4443743440, line=1, bind=0x0000000000000000, base_block=0x00007fff5fbfb370) + 266 at vm_eval.c:1274
	    frame #29: 0x0000000100206153 miniruby`eval_string_with_cref(self=4334412520, src=4443743520, cref=0x0000000000000000, file=52, line=1) + 197 at vm_eval.c:1307
	    frame #30: 0x0000000100206389 miniruby`rb_f_eval(argc=1, argv=0x0000000102400eb8, self=4334412520) + 219 at vm_eval.c:1382
	    frame #31: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_eval at vm_eval.c:1364), recv=4334412520, argc=1, argv=0x0000000102400eb8) + 47 at vm_insnhelper.c:1723
	    frame #32: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 386 at vm_insnhelper.c:1918
	    frame #33: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500d80, calling=0x00007fff5fbfbf50, ci=0x000000010263f240, cc=0x0000000100749b50) + 149 at vm_insnhelper.c:1934
	    frame #34: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #35: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #36: 0x00000001002093f8 miniruby`invoke_block(ec=0x00000001007d3548, iseq=0x000000010252d7f0, self=4334412520, captured=0x0000000102500df8, cref=0x0000000000000000, type=572653569, opt_pc=0) + 224 at vm.c:988
	    frame #37: 0x0000000100209766 miniruby`invoke_iseq_block_from_c(ec=0x00000001007d3548, captured=0x0000000102500df8, self=4334412520, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0) + 389 at vm.c:1040
	    frame #38: 0x0000000100209824 miniruby`invoke_block_from_c_bh(ec=0x00000001007d3548, block_handler=4333768185, argc=0, argv=0x0000000000000000, passed_block_handler=0, cref=0x0000000000000000, is_lambda=0, force_blockarg=0) + 138 at vm.c:1058
	    frame #39: 0x00000001002099d0 miniruby`vm_yield(ec=0x00000001007d3548, argc=0, argv=0x0000000000000000) + 69 at vm.c:1103
	    frame #40: 0x0000000100205623 miniruby`rb_yield_0(argc=0, argv=0x0000000000000000) + 40 at vm_eval.c:970
	    frame #41: 0x0000000100205964 miniruby`loop_i + 19 at vm_eval.c:1049
	    frame #42: 0x000000010007db07 miniruby`rb_rescue2(b_proc=(miniruby`loop_i at vm_eval.c:1047), data1=0, r_proc=(miniruby`loop_stop at vm_eval.c:1056), data2=0) + 369 at eval.c:896
	    frame #43: 0x0000000100205a2e miniruby`rb_f_loop(self=4334412520) + 121 at vm_eval.c:1100
	    frame #44: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_f_loop at vm_eval.c:1098), recv=4334412520, argc=0, argv=0x0000000102400e80) + 41 at vm_insnhelper.c:1729
	    frame #45: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 386 at vm_insnhelper.c:1918
	    frame #46: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 149 at vm_insnhelper.c:1934
	    frame #47: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 239 at vm_insnhelper.c:2232
	    frame #48: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 253 at vm_insnhelper.c:2366
	    frame #49: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500de0, calling=0x00007fff5fbfd4d0, ci=0x000000010263bbf0, cc=0x0000000102642118) + 59 at vm_insnhelper.c:2398
	    frame #50: 0x00000001001fab2f miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 7480 at insns.def:850
	    frame #51: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #52: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x000000010252dd90) + 52 at vm.c:2019
	    frame #53: 0x000000010007c768 miniruby`ruby_exec_internal(n=0x000000010252dd90) + 297 at eval.c:246
	    frame #54: 0x000000010007c88e miniruby`ruby_exec_node(n=0x000000010252dd90) + 36 at eval.c:310
	    frame #55: 0x000000010007c861 miniruby`ruby_run_node(n=0x000000010252dd90) + 62 at eval.c:302
	    frame #56: 0x000000010000138d miniruby`main(argc=2, argv=0x00007fff5fbfdbf0) + 113 at main.c:42
	    frame #57: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb) p ((struct RVALUE*)pathobj)->as.basic
	(RBasic) $0 = (flags = 0, klass = 4478683600)
	(lldb)

	fix SEGV inspecting uninitialized objects

	obj_info() assumes the given object is alive.  OTOH
	gc_writebarrier_incremental is called before or in middle of
	object initialization.  Can casue SEGV.

	(lldb) run
	Process 48188 launched: './miniruby' (x86_64)
	Process 48188 stopped
	* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
	    frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
	   2069 static inline const VALUE *
	   2070 rb_array_const_ptr(VALUE a)
	   2071 {
	-> 2072     return FIX_CONST_VALUE_PTR((RBASIC(a)->flags & RARRAY_EMBED_FLAG) ?
	   2073         RARRAY(a)->as.ary : RARRAY(a)->as.heap.ptr);
	   2074 }
	   2075
	(lldb) bt
	* thread #1: tid = 0x30fd53, 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
	  * frame #0: 0x00000001000bf7a9 miniruby`rb_array_const_ptr(a=5251291222225483145) + 12 at ruby.h:2072
	    frame #1: 0x00000001000bfaab miniruby`pathobj_path(pathobj=5251291222225483145) + 70 at vm_core.h:269
	    frame #2: 0x00000001000c25ff miniruby`rb_iseq_path(iseq=0x00000001025b71a8) + 32 at iseq.c:723
	    frame #3: 0x000000010009db09 miniruby`rb_raw_iseq_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, iseq=0x00000001025b71a8) + 69 at gc.c:9274
	    frame #4: 0x000000010009e1d5 miniruby`rb_raw_obj_info(buff="0x00000001025b7158 [0    ] proc (Proc)", buff_size=256, obj=4334514520) + 1546 at gc.c:9351
	    frame #5: 0x000000010009e4d5 miniruby`obj_info(obj=4334514520) + 98 at gc.c:9429
	    frame #6: 0x0000000100096658 miniruby`gc_writebarrier_incremental(a=4334514520, b=4334514600, objspace=0x00000001007d3280) + 61 at gc.c:5963
	    frame #7: 0x00000001000968ca miniruby`rb_gc_writebarrier(a=4334514520, b=4334514600) + 127 at gc.c:6009
	    frame #8: 0x00000001001eabe0 miniruby`rb_obj_written(a=4334514520, oldv=52, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 72 at ruby.h:1472
	    frame #9: 0x00000001001eac2c miniruby`rb_obj_write(a=4334514520, slot=0x000000010259ff10, b=4334514600, filename="/Users/urabe.shyouhei/data/src/pedantic/vm.c", line=821) + 70 at ruby.h:1489
	    frame #10: 0x0000000100208b6f miniruby`vm_proc_create_from_captured(klass=4311027960, captured=0x0000000102500338, block_type=block_type_ifunc, is_from_method='\0', is_lambda='\x01') + 137 at vm.c:821
	    frame #11: 0x0000000100208e5c miniruby`rb_vm_make_proc_lambda(ec=0x00000001007d3548, captured=0x0000000102500338, klass=4311027960, is_lambda='\x01') + 134 at vm.c:892
	    frame #12: 0x000000010011f08e miniruby`proc_new(klass=4311027960, is_lambda='\x01') + 445 at proc.c:752
	    frame #13: 0x000000010011f110 miniruby`rb_block_lambda + 27 at proc.c:808
	    frame #14: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`rb_block_lambda at proc.c:807), recv=4310991600, argc=0, argv=0x0000000000000000) + 41 at vm_insnhelper.c:1729
	    frame #15: 0x00000001002033de miniruby`vm_call0_cfunc_with_frame(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 370 at vm_eval.c:85
	    frame #16: 0x00000001002034d9 miniruby`vm_call0_cfunc(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 59 at vm_eval.c:100
	    frame #17: 0x000000010020368f miniruby`vm_call0_body(ec=0x00000001007d3548, calling=0x00007fff5fbfb080, ci=0x00007fff5fbfb070, cc=0x00007fff5fbfb0a0, argv=0x0000000000000000) + 436 at vm_eval.c:131
	    frame #18: 0x000000010020326a miniruby`vm_call0(ec=0x00000001007d3548, recv=4310991600, id=2993, argc=0, argv=0x0000000000000000, me=0x0000000100f48110) + 142 at vm_eval.c:58
	    frame #19: 0x0000000100203c60 miniruby`rb_call0(ec=0x00000001007d3548, recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL, self=4334514640) + 166 at vm_eval.c:296
	    frame #20: 0x0000000100204827 miniruby`rb_call(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000, scope=CALL_FCALL) + 84 at vm_eval.c:589
	    frame #21: 0x000000010020518b miniruby`rb_funcallv(recv=4310991600, mid=2993, argc=0, argv=0x0000000000000000) + 52 at vm_eval.c:815
	    frame #22: 0x000000010012242e miniruby`mlambda(method=0) + 45 at proc.c:2661
	    frame #23: 0x0000000100205bac miniruby`rb_iterate0(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, ifunc=0x00000001025b71a8, ec=0x00000001007d3548) + 380 at vm_eval.c:1134
	    frame #24: 0x0000000100205d16 miniruby`rb_iterate(it_proc=(miniruby`mlambda at proc.c:2660), data1=0, bl_proc=(miniruby`bmcall at proc.c:2666), data2=4334514640) + 88 at vm_eval.c:1166
	    frame #25: 0x00000001001224c7 miniruby`method_to_proc(method=4334514640) + 43 at proc.c:2701
	    frame #26: 0x00000001001f24a7 miniruby`call_cfunc_0(func=(miniruby`method_to_proc at proc.c:2688), recv=4334514640, argc=0, argv=0x0000000102400568) + 41 at vm_insnhelper.c:1729
	    frame #27: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 386 at vm_insnhelper.c:1918
	    frame #28: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 149 at vm_insnhelper.c:1934
	    frame #29: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 239 at vm_insnhelper.c:2232
	    frame #30: 0x00000001001f49a4 miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 117 at vm_insnhelper.c:2355
	    frame #31: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x0000000102500350, calling=0x00007fff5fbfc030, ci=0x0000000100f2ec70, cc=0x0000000102735718) + 59 at vm_insnhelper.c:2398
	    frame #32: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #33: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #34: 0x000000010020c3d1 miniruby`rb_iseq_eval(iseq=0x00000001007f8270) + 52 at vm.c:2008
	    frame #35: 0x00000001000caa4a miniruby`rb_load_internal0(ec=0x00000001007d3548, fname=4310799960, wrap=0) + 631 at load.c:611
	    frame #36: 0x00000001000cab36 miniruby`rb_load_internal(fname=4310799960, wrap=0) + 46 at load.c:642
	    frame #37: 0x00000001000cae1d miniruby`rb_f_load(argc=1, argv=0x00000001024004b8) + 217 at load.c:710
	    frame #38: 0x00000001001f247c miniruby`call_cfunc_m1(func=(miniruby`rb_f_load at load.c:695), recv=4311327440, argc=1, argv=0x00000001024004b8) + 47 at vm_insnhelper.c:1723
	    frame #39: 0x00000001001f2f87 miniruby`vm_call_cfunc_with_frame(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 386 at vm_insnhelper.c:1918
	    frame #40: 0x00000001001f30d6 miniruby`vm_call_cfunc(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 149 at vm_insnhelper.c:1934
	    frame #41: 0x00000001001f4319 miniruby`vm_call_method_each_type(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 239 at vm_insnhelper.c:2232
	    frame #42: 0x00000001001f4a2c miniruby`vm_call_method(ec=0x00000001007d3548, cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 253 at vm_insnhelper.c:2366
	    frame #43: 0x00000001001f4b7a miniruby`vm_call_general(ec=0x00000001007d3548, reg_cfp=0x00000001025003e0, calling=0x00007fff5fbfd3e0, ci=0x0000000102541070, cc=0x0000000100f9e918) + 59 at vm_insnhelper.c:2398
	    frame #44: 0x00000001001faf0e miniruby`vm_exec_core(ec=0x00000001007d3548, initial=0) + 8471 at insns.def:915
	    frame #45: 0x000000010020b75d miniruby`vm_exec(ec=0x00000001007d3548) + 230 at vm.c:1771
	    frame #46: 0x000000010020c40f miniruby`rb_iseq_eval_main(iseq=0x0000000100f21240) + 52 at vm.c:2019
	    frame #47: 0x000000010007c774 miniruby`ruby_exec_internal(n=0x0000000100f21240) + 297 at eval.c:246
	    frame #48: 0x000000010007c89a miniruby`ruby_exec_node(n=0x0000000100f21240) + 36 at eval.c:310
	    frame #49: 0x000000010007c86d miniruby`ruby_run_node(n=0x0000000100f21240) + 62 at eval.c:302
	    frame #50: 0x0000000100001399 miniruby`main(argc=9, argv=0x00007fff5fbfdae0) + 113 at main.c:42
	    frame #51: 0x00007fff88eda5ad libdyld.dylib`start + 1
	(lldb)

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@62941 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This funcion can be called from inside of rb_ast_new().
Should add appropriate case branches.

(lldb) run
Process 9135 launched: './miniruby' (x86_64)
Process 9135 stopped
* thread #1: tid = 0xdf36b, 0x00000001000ca4f9 miniruby`rb_raw_obj_info(buff="0x000000010205d158 [0    ] T_IMEMO", buff_size=256, obj=4328903000) + 2361 at gc.c:9617, queue = 'com.apple.main-thread', stop reason = EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
    frame #0: 0x00000001000ca4f9 miniruby`rb_raw_obj_info(buff="0x000000010205d158 [0    ] T_IMEMO", buff_size=256, obj=4328903000) + 2361 at gc.c:9617
   9614                 IMEMO_NAME(iseq);
   9615                 IMEMO_NAME(tmpbuf);
   9616 #undef IMEMO_NAME
-> 9617               default: UNREACHABLE;
   9618             }
   9619             snprintf(buff, buff_size, "%s %s", buff, imemo_name);
   9620
(lldb) bt
* thread #1: tid = 0xdf36b, 0x00000001000ca4f9 miniruby`rb_raw_obj_info(buff="0x000000010205d158 [0    ] T_IMEMO", buff_size=256, obj=4328903000) + 2361 at gc.c:9617, queue = 'com.apple.main-thread', stop reason = EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
  * frame #0: 0x00000001000ca4f9 miniruby`rb_raw_obj_info(buff="0x000000010205d158 [0    ] T_IMEMO", buff_size=256, obj=4328903000) + 2361 at gc.c:9617
    frame #1: 0x00000001000c433f miniruby`obj_info(obj=4328903000) + 95 at gc.c:9671
    frame #2: 0x00000001000ce2ac miniruby`newobj_init(klass=4302478608, flags=36890, v1=0, v2=0, v3=0, wb_protected=1, objspace=0x0000000101800410, obj=4328903000) + 444 at gc.c:1882
    frame #3: 0x00000001000c0a49 miniruby`newobj_of(klass=4302478608, flags=36890, v1=0, v2=0, v3=0, wb_protected=1) + 217 at gc.c:1968
    frame #4: 0x00000001000c0bcb miniruby`rb_imemo_new(type=imemo_ast, v1=0, v2=0, v3=0, v0=4302478608) + 75 at gc.c:2017
    frame #5: 0x0000000100148f2a miniruby`rb_ast_new + 58 at node.c:1118
    frame #6: 0x000000010018d9e2 miniruby`yycompile(vparser=4328903720, p=0x0000000100729670, fname=4328903160, line=1) + 98 at parse.y:4925
    frame #7: 0x000000010018d66f miniruby`parser_compile_string(vparser=4328903720, fname=4328903160, s=4328904440, line=1) + 143 at parse.y:4995
    frame #8: 0x000000010018d768 miniruby`rb_parser_compile_string_path(vparser=4328903720, f=4328903160, s=4328904440, line=1) + 56 at parse.y:5015
    frame #9: 0x000000010018d71e miniruby`rb_parser_compile_string(vparser=4328903720, f="-e", s=4328904440, line=1) + 62 at parse.y:5008
    frame #10: 0x00000001002130d5 miniruby`process_options(argc=0, argv=0x00007fff5fbfdc08, opt=0x00007fff5fbfd9e8) + 3477 at ruby.c:1754
    frame #11: 0x00000001002122dd miniruby`ruby_process_options(argc=2, argv=0x00007fff5fbfdbf8) + 285 at ruby.c:2332
    frame #12: 0x00000001000aa966 miniruby`ruby_options(argc=2, argv=0x00007fff5fbfdbf8) + 262 at eval.c:118
    frame #13: 0x0000000100000ed4 miniruby`main(argc=2, argv=0x00007fff5fbfdbf8) + 116 at main.c:42
    frame #14: 0x00007fff933845ad libdyld.dylib`start + 1
    frame #15: 0x00007fff933845ad libdyld.dylib`start + 1
(lldb)


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65148 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

This is rather nitpicking but at the moment the process terminates,
heap_pages_final_slots overflows.

(lldb) bt
* thread #1: tid = 0xc0903, 0x00000001002b3bf7 miniruby`finalize_list(objspace=0x0000000101c09240, zombie=4329149840) + 999 at gc.c:2946, queue = 'com.apple.main-thread', stop reason = EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
  * frame #0: 0x00000001002b3bf7 miniruby`finalize_list(objspace=0x0000000101c09240, zombie=4329149840) + 999 at gc.c:2946
    frame #1: 0x000000010026a69e miniruby`rb_objspace_call_finalizer(objspace=0x0000000101c09240) + 7118 at gc.c:3092
    frame #2: 0x0000000100268ac5 miniruby`rb_gc_call_finalizer_at_exit + 149 at gc.c:3015
    frame #3: 0x00000001002272bc miniruby`ruby_finalize_1 + 156 at eval.c:146
    frame #4: 0x00000001002282b6 miniruby`ruby_cleanup(ex=0) + 4070 at eval.c:238
    frame #5: 0x0000000100228785 miniruby`ruby_run_node(n=0x0000000102060ad8) + 85 at eval.c:317
    frame #6: 0x0000000100000b9c miniruby`main(argc=2, argv=0x00007fff5fbfdc38) + 124 at main.c:42
    frame #7: 0x00007fff9966a5ad libdyld.dylib`start + 1
    frame #8: 0x00007fff9966a5ad libdyld.dylib`start + 1
(lldb) p objspace->heap_pages
(rb_objspace::(anonymous struct)) $0 = {
  sorted = 0x0000000101c070b0
  allocated_pages = 24
  allocatable_pages = 0
  sorted_length = 24
  range = {
    [0] = 0x0000000102020028
    [1] = 0x00000001020dbfd0
  }
  freeable_pages = 0
  final_slots = 0
  deferred_final = 4329149840
}
(lldb)




git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65633 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

memo.float_value might change inside of hash_sum.  In case it
flipped from false to true there, and the calculated sum is Inf,
memo.c might not be initialized at all.  This is bad.

Found using memory sanitizer:

==55293==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x55dfb8d6c529 in rb_float_new_inline internal.h:1814:53
    #1 0x55dfb8d1b30c in enum_sum enum.c:4017:18
    #2 0x55dfb86d75ad in call_cfunc_m1 vm_insnhelper.c:2041:12
    #3 0x55dfb864b141 in vm_call_cfunc_with_frame vm_insnhelper.c:2207:11
    #4 0x55dfb85e843d in vm_call_cfunc vm_insnhelper.c:2225:12
    #5 0x55dfb85e08f3 in vm_call_method_each_type vm_insnhelper.c:2560:9
    #6 0x55dfb85de9c7 in vm_call_method vm_insnhelper.c:2686:13
    #7 0x55dfb849eac6 in vm_call_general vm_insnhelper.c:2730:12
    #8 0x55dfb8686103 in vm_sendish vm_insnhelper.c:3623:11
    #9 0x55dfb84dc29e in vm_exec_core insns.def:789:11

	Fix use-after-free in constant cache

	[Bug #20921]

	When we create a cache entry for a constant, the following sequence of
	events could happen:

	- vm_track_constant_cache is called to insert a constant cache.
	- In vm_track_constant_cache, we first look up the ST table for the ID
	  of the constant. Assume the ST table exists because another iseq also
	  holds a cache entry for this ID.
	- We then insert into this ST table with the iseq_inline_constant_cache.
	- However, while inserting into this ST table, it allocates memory, which
	  could trigger a GC. Assume that it does trigger a GC.
	- The GC frees the one and only other iseq that holds a cache entry for
	  this ID.
	- In remove_from_constant_cache, it will appear that the ST table is now
	  empty because there are no more iseq with cache entries for this ID, so
	  we free the ST table.
	- We complete GC and continue our st_insert. However, this ST table has
	  been freed so we now have a use-after-free.

	This issue is very hard to reproduce, because it requires that the GC runs
	at a very specific time. However, we can make it show up by applying this
	patch which runs GC right before the st_insert to mimic the st_insert
	triggering a GC:

	    diff --git a/vm_insnhelper.c b/vm_insnhelper.c
	    index 3cb23f0..a93998136a 100644
	    --- a/vm_insnhelper.c
	    +++ b/vm_insnhelper.c
	    @@ -6338,6 +6338,10 @@ vm_track_constant_cache(ID id, void *ic)
	            rb_id_table_insert(const_cache, id, (VALUE)ics);
	        }

	    +    if (id == rb_intern("MyConstant")) rb_gc();
	    +
	        st_insert(ics, (st_data_t) ic, (st_data_t) Qtrue);
	    }

	And if we run this script:

	    Object.const_set("MyConstant", "Hello!")

	    my_proc = eval("-> { MyConstant }")
	    my_proc.call

	    my_proc = eval("-> { MyConstant }")
	    my_proc.call

	We can see that ASAN outputs a use-after-free error:

	    ==36540==ERROR: AddressSanitizer: heap-use-after-free on address 0x606000049528 at pc 0x000102f3ceac bp 0x00016d607a70 sp 0x00016d607a68
	    READ of size 8 at 0x606000049528 thread T0
	        #0 0x102f3cea8 in do_hash st.c:321
	        #1 0x102f3ddd0 in rb_st_insert st.c:1132
	        #2 0x103140700 in vm_track_constant_cache vm_insnhelper.c:6345
	        #3 0x1030b91d8 in vm_ic_track_const_chain vm_insnhelper.c:6356
	        #4 0x1030b8cf8 in rb_vm_opt_getconstant_path vm_insnhelper.c:6424
	        #5 0x1030bc1e0 in vm_exec_core insns.def:263
	        #6 0x1030b55fc in rb_vm_exec vm.c:2585
	        #7 0x1030fe0ac in rb_iseq_eval_main vm.c:2851
	        #8 0x102a82588 in rb_ec_exec_node eval.c:281
	        #9 0x102a81fe0 in ruby_run_node eval.c:319
	        #10 0x1027f3db4 in rb_main main.c:43
	        #11 0x1027f3bd4 in main main.c:68
	        #12 0x183900270  (<unknown module>)

	    0x606000049528 is located 8 bytes inside of 56-byte region [0x606000049520,0x606000049558)
	    freed by thread T0 here:
	        #0 0x104174d40 in free+0x98 (libclang_rt.asan_osx_dynamic.dylib:arm64e+0x54d40)
	        #1 0x102ada89c in rb_gc_impl_free default.c:8183
	        #2 0x102ada7dc in ruby_sized_xfree gc.c:4507
	        #3 0x102ac4d34 in ruby_xfree gc.c:4518
	        #4 0x102f3cb34 in rb_st_free_table st.c:663
	        #5 0x102bd52d8 in remove_from_constant_cache iseq.c:119
	        #6 0x102bbe2cc in iseq_clear_ic_references iseq.c:153
	        #7 0x102bbd2a0 in rb_iseq_free iseq.c:166
	        #8 0x102b32ed0 in rb_imemo_free imemo.c:564
	        #9 0x102ac4b44 in rb_gc_obj_free gc.c:1407
	        #10 0x102af4290 in gc_sweep_plane default.c:3546
	        #11 0x102af3bdc in gc_sweep_page default.c:3634
	        #12 0x102aeb140 in gc_sweep_step default.c:3906
	        #13 0x102aeadf0 in gc_sweep_rest default.c:3978
	        #14 0x102ae4714 in gc_sweep default.c:4155
	        #15 0x102af8474 in gc_start default.c:6484
	        #16 0x102afbe30 in garbage_collect default.c:6363
	        #17 0x102ad37f0 in rb_gc_impl_start default.c:6816
	        #18 0x102ad3634 in rb_gc gc.c:3624
	        #19 0x1031406ec in vm_track_constant_cache vm_insnhelper.c:6342
	        #20 0x1030b91d8 in vm_ic_track_const_chain vm_insnhelper.c:6356
	        #21 0x1030b8cf8 in rb_vm_opt_getconstant_path vm_insnhelper.c:6424
	        #22 0x1030bc1e0 in vm_exec_core insns.def:263
	        #23 0x1030b55fc in rb_vm_exec vm.c:2585
	        #24 0x1030fe0ac in rb_iseq_eval_main vm.c:2851
	        #25 0x102a82588 in rb_ec_exec_node eval.c:281
	        #26 0x102a81fe0 in ruby_run_node eval.c:319
	        #27 0x1027f3db4 in rb_main main.c:43
	        #28 0x1027f3bd4 in main main.c:68
	        #29 0x183900270  (<unknown module>)

	    previously allocated by thread T0 here:
	        #0 0x104174c04 in malloc+0x94 (libclang_rt.asan_osx_dynamic.dylib:arm64e+0x54c04)
	        #1 0x102ada0ec in rb_gc_impl_malloc default.c:8198
	        #2 0x102acee44 in ruby_xmalloc gc.c:4438
	        #3 0x102f3c85c in rb_st_init_table_with_size st.c:571
	        #4 0x102f3c900 in rb_st_init_table st.c:600
	        #5 0x102f3c920 in rb_st_init_numtable st.c:608
	        #6 0x103140698 in vm_track_constant_cache vm_insnhelper.c:6337
	        #7 0x1030b91d8 in vm_ic_track_const_chain vm_insnhelper.c:6356
	        #8 0x1030b8cf8 in rb_vm_opt_getconstant_path vm_insnhelper.c:6424
	        #9 0x1030bc1e0 in vm_exec_core insns.def:263
	        #10 0x1030b55fc in rb_vm_exec vm.c:2585
	        #11 0x1030fe0ac in rb_iseq_eval_main vm.c:2851
	        #12 0x102a82588 in rb_ec_exec_node eval.c:281
	        #13 0x102a81fe0 in ruby_run_node eval.c:319
	        #14 0x1027f3db4 in rb_main main.c:43
	        #15 0x1027f3bd4 in main main.c:68
	        #16 0x183900270  (<unknown module>)

	This commit fixes this bug by adding a inserting_constant_cache_id field
	to the VM, which stores the ID that is currently being inserted and, in
	remove_from_constant_cache, we don't free the ST table for ID equal to
	this one.

	Co-Authored-By: Alan Wu <[email protected]>

Update README [ci skip] [DOC].

[Bug #18119]

When we create classes, it pushes the class to the subclass list of the
superclass. This access needs to be synchronized because multiple Ractors
may be creating classes with the same superclass, which would cause race
conditions and cause the linked list to be corrupted.

For example, we can reproduce with this script crashing:

    workers = (0...8).map do
      Ractor.new do
        loop do
          100.times.map { Class.new }
          Ractor.yield nil
        end
      end
    end

    100.times { Ractor.select(*workers) }

With ASAN enabled, we can see that there are use-after-free errors:

    ==176013==ERROR: AddressSanitizer: heap-use-after-free on address 0x5030000974f0 at pc 0x62f9e56f892d bp 0x7a503f1ffd90 sp 0x7a503f1ffd88
    WRITE of size 8 at 0x5030000974f0 thread T4
        #0 0x62f9e56f892c in rb_class_remove_from_super_subclasses class.c:149:24
        #1 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#2 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#3 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#4 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#5 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
        ruby#6 0x62f9e58fac93 in gc_start gc/default/default.c:6402:13
        ruby#7 0x62f9e58e8b69 in heap_prepare gc/default/default.c:2032:13
        ruby#8 0x62f9e58e8b69 in heap_next_free_page gc/default/default.c:2255:9
        ruby#9 0x62f9e58e8b69 in newobj_cache_miss gc/default/default.c:2362:38
    ...
    0x5030000974f0 is located 16 bytes inside of 24-byte region [0x5030000974e0,0x5030000974f8)
    freed by thread T4 here:
        #0 0x62f9e562f28a in free (miniruby+0x1fd28a) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58ca2ab in rb_gc_impl_free gc/default/default.c:8102:9
        ruby#2 0x62f9e58ca2ab in ruby_sized_xfree gc.c:5029:13
        ruby#3 0x62f9e58ca2ab in ruby_xfree gc.c:5040:5
        ruby#4 0x62f9e56f88e6 in rb_class_remove_from_super_subclasses class.c:152:9
        ruby#5 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#6 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#7 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#8 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#9 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
    ...
    previously allocated by thread T5 here:
        #0 0x62f9e562f70d in calloc (miniruby+0x1fd70d) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58c8e1a in calloc1 gc/default/default.c:1472:12
        ruby#2 0x62f9e58c8e1a in rb_gc_impl_calloc gc/default/default.c:8138:5
        ruby#3 0x62f9e58c8e1a in ruby_xcalloc_body gc.c:4964:12
        ruby#4 0x62f9e58c8e1a in ruby_xcalloc gc.c:4958:34
        ruby#5 0x62f9e56f906e in push_subclass_entry_to_list class.c:88:13
        ruby#6 0x62f9e56f906e in rb_class_subclass_add class.c:111:38
        ruby#7 0x62f9e56f906e in RCLASS_SET_SUPER internal/class.h:257:9
        ruby#8 0x62f9e56fca7a in make_metaclass class.c:786:5
        ruby#9 0x62f9e59db982 in rb_class_initialize object.c:2101:5

[Bug #18119]

When we create classes, it pushes the class to the subclass list of the
superclass. This access needs to be synchronized because multiple Ractors
may be creating classes with the same superclass, which would cause race
conditions and cause the linked list to be corrupted.

For example, we can reproduce with this script crashing:

    workers = (0...8).map do
      Ractor.new do
        loop do
          100.times.map { Class.new }
          Ractor.yield nil
        end
      end
    end

    100.times { Ractor.select(*workers) }

With ASAN enabled, we can see that there are use-after-free errors:

    ==176013==ERROR: AddressSanitizer: heap-use-after-free on address 0x5030000974f0 at pc 0x62f9e56f892d bp 0x7a503f1ffd90 sp 0x7a503f1ffd88
    WRITE of size 8 at 0x5030000974f0 thread T4
        #0 0x62f9e56f892c in rb_class_remove_from_super_subclasses class.c:149:24
        #1 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#2 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#3 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#4 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#5 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
        ruby#6 0x62f9e58fac93 in gc_start gc/default/default.c:6402:13
        ruby#7 0x62f9e58e8b69 in heap_prepare gc/default/default.c:2032:13
        ruby#8 0x62f9e58e8b69 in heap_next_free_page gc/default/default.c:2255:9
        ruby#9 0x62f9e58e8b69 in newobj_cache_miss gc/default/default.c:2362:38
    ...
    0x5030000974f0 is located 16 bytes inside of 24-byte region [0x5030000974e0,0x5030000974f8)
    freed by thread T4 here:
        #0 0x62f9e562f28a in free (miniruby+0x1fd28a) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58ca2ab in rb_gc_impl_free gc/default/default.c:8102:9
        ruby#2 0x62f9e58ca2ab in ruby_sized_xfree gc.c:5029:13
        ruby#3 0x62f9e58ca2ab in ruby_xfree gc.c:5040:5
        ruby#4 0x62f9e56f88e6 in rb_class_remove_from_super_subclasses class.c:152:9
        ruby#5 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#6 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#7 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#8 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#9 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
    ...
    previously allocated by thread T5 here:
        #0 0x62f9e562f70d in calloc (miniruby+0x1fd70d) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58c8e1a in calloc1 gc/default/default.c:1472:12
        ruby#2 0x62f9e58c8e1a in rb_gc_impl_calloc gc/default/default.c:8138:5
        ruby#3 0x62f9e58c8e1a in ruby_xcalloc_body gc.c:4964:12
        ruby#4 0x62f9e58c8e1a in ruby_xcalloc gc.c:4958:34
        ruby#5 0x62f9e56f906e in push_subclass_entry_to_list class.c:88:13
        ruby#6 0x62f9e56f906e in rb_class_subclass_add class.c:111:38
        ruby#7 0x62f9e56f906e in RCLASS_SET_SUPER internal/class.h:257:9
        ruby#8 0x62f9e56fca7a in make_metaclass class.c:786:5
        ruby#9 0x62f9e59db982 in rb_class_initialize object.c:2101:5

[Bug #18119]

When we create classes, it pushes the class to the subclass list of the
superclass. This access needs to be synchronized because multiple Ractors
may be creating classes with the same superclass, which would cause race
conditions and cause the linked list to be corrupted.

For example, we can reproduce with this script crashing:

    workers = (0...8).map do
      Ractor.new do
        loop do
          100.times.map { Class.new }
          Ractor.yield nil
        end
      end
    end

    100.times { Ractor.select(*workers) }

With ASAN enabled, we can see that there are use-after-free errors:

    ==176013==ERROR: AddressSanitizer: heap-use-after-free on address 0x5030000974f0 at pc 0x62f9e56f892d bp 0x7a503f1ffd90 sp 0x7a503f1ffd88
    WRITE of size 8 at 0x5030000974f0 thread T4
        #0 0x62f9e56f892c in rb_class_remove_from_super_subclasses class.c:149:24
        #1 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#2 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#3 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#4 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#5 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
        ruby#6 0x62f9e58fac93 in gc_start gc/default/default.c:6402:13
        ruby#7 0x62f9e58e8b69 in heap_prepare gc/default/default.c:2032:13
        ruby#8 0x62f9e58e8b69 in heap_next_free_page gc/default/default.c:2255:9
        ruby#9 0x62f9e58e8b69 in newobj_cache_miss gc/default/default.c:2362:38
    ...
    0x5030000974f0 is located 16 bytes inside of 24-byte region [0x5030000974e0,0x5030000974f8)
    freed by thread T4 here:
        #0 0x62f9e562f28a in free (miniruby+0x1fd28a) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58ca2ab in rb_gc_impl_free gc/default/default.c:8102:9
        ruby#2 0x62f9e58ca2ab in ruby_sized_xfree gc.c:5029:13
        ruby#3 0x62f9e58ca2ab in ruby_xfree gc.c:5040:5
        ruby#4 0x62f9e56f88e6 in rb_class_remove_from_super_subclasses class.c:152:9
        ruby#5 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#6 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#7 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#8 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#9 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
    ...
    previously allocated by thread T5 here:
        #0 0x62f9e562f70d in calloc (miniruby+0x1fd70d) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58c8e1a in calloc1 gc/default/default.c:1472:12
        ruby#2 0x62f9e58c8e1a in rb_gc_impl_calloc gc/default/default.c:8138:5
        ruby#3 0x62f9e58c8e1a in ruby_xcalloc_body gc.c:4964:12
        ruby#4 0x62f9e58c8e1a in ruby_xcalloc gc.c:4958:34
        ruby#5 0x62f9e56f906e in push_subclass_entry_to_list class.c:88:13
        ruby#6 0x62f9e56f906e in rb_class_subclass_add class.c:111:38
        ruby#7 0x62f9e56f906e in RCLASS_SET_SUPER internal/class.h:257:9
        ruby#8 0x62f9e56fca7a in make_metaclass class.c:786:5
        ruby#9 0x62f9e59db982 in rb_class_initialize object.c:2101:5

[Bug #18119]

When we create classes, it pushes the class to the subclass list of the
superclass. This access needs to be synchronized because multiple Ractors
may be creating classes with the same superclass, which would cause race
conditions and cause the linked list to be corrupted.

For example, we can reproduce with this script crashing:

    workers = (0...8).map do
      Ractor.new do
        loop do
          100.times.map { Class.new }
          Ractor.yield nil
        end
      end
    end

    100.times { Ractor.select(*workers) }

With ASAN enabled, we can see that there are use-after-free errors:

    ==176013==ERROR: AddressSanitizer: heap-use-after-free on address 0x5030000974f0 at pc 0x62f9e56f892d bp 0x7a503f1ffd90 sp 0x7a503f1ffd88
    WRITE of size 8 at 0x5030000974f0 thread T4
        #0 0x62f9e56f892c in rb_class_remove_from_super_subclasses class.c:149:24
        #1 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#2 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#3 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#4 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#5 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
        ruby#6 0x62f9e58fac93 in gc_start gc/default/default.c:6402:13
        ruby#7 0x62f9e58e8b69 in heap_prepare gc/default/default.c:2032:13
        ruby#8 0x62f9e58e8b69 in heap_next_free_page gc/default/default.c:2255:9
        ruby#9 0x62f9e58e8b69 in newobj_cache_miss gc/default/default.c:2362:38
    ...
    0x5030000974f0 is located 16 bytes inside of 24-byte region [0x5030000974e0,0x5030000974f8)
    freed by thread T4 here:
        #0 0x62f9e562f28a in free (miniruby+0x1fd28a) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58ca2ab in rb_gc_impl_free gc/default/default.c:8102:9
        ruby#2 0x62f9e58ca2ab in ruby_sized_xfree gc.c:5029:13
        ruby#3 0x62f9e58ca2ab in ruby_xfree gc.c:5040:5
        ruby#4 0x62f9e56f88e6 in rb_class_remove_from_super_subclasses class.c:152:9
        ruby#5 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        ruby#6 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        ruby#7 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        ruby#8 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        ruby#9 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
    ...
    previously allocated by thread T5 here:
        #0 0x62f9e562f70d in calloc (miniruby+0x1fd70d) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58c8e1a in calloc1 gc/default/default.c:1472:12
        ruby#2 0x62f9e58c8e1a in rb_gc_impl_calloc gc/default/default.c:8138:5
        ruby#3 0x62f9e58c8e1a in ruby_xcalloc_body gc.c:4964:12
        ruby#4 0x62f9e58c8e1a in ruby_xcalloc gc.c:4958:34
        ruby#5 0x62f9e56f906e in push_subclass_entry_to_list class.c:88:13
        ruby#6 0x62f9e56f906e in rb_class_subclass_add class.c:111:38
        ruby#7 0x62f9e56f906e in RCLASS_SET_SUPER internal/class.h:257:9
        ruby#8 0x62f9e56fca7a in make_metaclass class.c:786:5
        ruby#9 0x62f9e59db982 in rb_class_initialize object.c:2101:5

[Bug #18119]

When we create classes, it pushes the class to the subclass list of the
superclass. This access needs to be synchronized because multiple Ractors
may be creating classes with the same superclass, which would cause race
conditions and cause the linked list to be corrupted.

For example, we can reproduce with this script crashing:

    workers = (0...8).map do
      Ractor.new do
        loop do
          100.times.map { Class.new }
          Ractor.yield nil
        end
      end
    end

    100.times { Ractor.select(*workers) }

With ASAN enabled, we can see that there are use-after-free errors:

    ==176013==ERROR: AddressSanitizer: heap-use-after-free on address 0x5030000974f0 at pc 0x62f9e56f892d bp 0x7a503f1ffd90 sp 0x7a503f1ffd88
    WRITE of size 8 at 0x5030000974f0 thread T4
        #0 0x62f9e56f892c in rb_class_remove_from_super_subclasses class.c:149:24
        #1 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        #2 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        #3 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        #4 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        #5 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
        #6 0x62f9e58fac93 in gc_start gc/default/default.c:6402:13
        #7 0x62f9e58e8b69 in heap_prepare gc/default/default.c:2032:13
        #8 0x62f9e58e8b69 in heap_next_free_page gc/default/default.c:2255:9
        #9 0x62f9e58e8b69 in newobj_cache_miss gc/default/default.c:2362:38
    ...
    0x5030000974f0 is located 16 bytes inside of 24-byte region [0x5030000974e0,0x5030000974f8)
    freed by thread T4 here:
        #0 0x62f9e562f28a in free (miniruby+0x1fd28a) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58ca2ab in rb_gc_impl_free gc/default/default.c:8102:9
        #2 0x62f9e58ca2ab in ruby_sized_xfree gc.c:5029:13
        #3 0x62f9e58ca2ab in ruby_xfree gc.c:5040:5
        #4 0x62f9e56f88e6 in rb_class_remove_from_super_subclasses class.c:152:9
        #5 0x62f9e58c9dd2 in rb_gc_obj_free gc.c:1262:9
        #6 0x62f9e58f6e19 in gc_sweep_plane gc/default/default.c:3450:21
        #7 0x62f9e58f686a in gc_sweep_page gc/default/default.c:3535:13
        #8 0x62f9e58f12b4 in gc_sweep_step gc/default/default.c:3810:9
        #9 0x62f9e58ed2a7 in gc_sweep gc/default/default.c:4058:13
    ...
    previously allocated by thread T5 here:
        #0 0x62f9e562f70d in calloc (miniruby+0x1fd70d) (BuildId: 5ad6d9e7cec8318df6726ea5ce34d3c76d0d0233)
        #1 0x62f9e58c8e1a in calloc1 gc/default/default.c:1472:12
        #2 0x62f9e58c8e1a in rb_gc_impl_calloc gc/default/default.c:8138:5
        #3 0x62f9e58c8e1a in ruby_xcalloc_body gc.c:4964:12
        #4 0x62f9e58c8e1a in ruby_xcalloc gc.c:4958:34
        #5 0x62f9e56f906e in push_subclass_entry_to_list class.c:88:13
        #6 0x62f9e56f906e in rb_class_subclass_add class.c:111:38
        #7 0x62f9e56f906e in RCLASS_SET_SUPER internal/class.h:257:9
        #8 0x62f9e56fca7a in make_metaclass class.c:786:5
        #9 0x62f9e59db982 in rb_class_initialize object.c:2101:5

In commit d42b9ff, an optimization was introduced that can speed up
Regexp#match by 15% when it matches with strings of different encodings.
This optimization, however, does not work across ractors. To fix this,
we only use the optimization if no ractors have been started. In the
future, we could use atomics for the reference counting if we find it's
needed and if it's more performant.

The backtrace of the misbehaving native thread:

```
  * frame #0: 0x0000000189c94388 libsystem_kernel.dylib`__pthread_kill + 8
    frame ruby#1: 0x0000000189ccd88c libsystem_pthread.dylib`pthread_kill + 296
    frame ruby#2: 0x0000000189bd6c60 libsystem_c.dylib`abort + 124
    frame ruby#3: 0x0000000189adb174 libsystem_malloc.dylib`malloc_vreport + 892
    frame ruby#4: 0x0000000189adec90 libsystem_malloc.dylib`malloc_report + 64
    frame ruby#5: 0x0000000189ae321c libsystem_malloc.dylib`___BUG_IN_CLIENT_OF_LIBMALLOC_POINTER_BEING_FREED_WAS_NOT_ALLOCATED + 32
    frame ruby#6: 0x00000001001c3be4 ruby`onig_free_body(reg=0x000000012d84b660) at regcomp.c:5663:5
    frame ruby#7: 0x00000001001ba828 ruby`rb_reg_prepare_re(re=4748462304, str=4748451168) at re.c:1680:13
    frame ruby#8: 0x00000001001bac58 ruby`rb_reg_onig_match(re=4748462304, str=4748451168, match=(ruby`reg_onig_search [inlined] rbimpl_RB_TYPE_P_fastpath at value_type.h:349:14
ruby`reg_onig_search [inlined] rbimpl_rstring_getmem at rstring.h:391:5
ruby`reg_onig_search at re.c:1781:5), args=0x000000013824b168, regs=0x000000013824b150) at re.c:1708:20
    frame ruby#9: 0x00000001001baefc ruby`rb_reg_search_set_match(re=4748462304, str=4748451168, pos=<unavailable>, reverse=0, set_backref_str=1, set_match=0x0000000000000000) at re.c:1809:27
    frame ruby#10: 0x00000001001bae80 ruby`rb_reg_search0(re=<unavailable>, str=<unavailable>, pos=<unavailable>, reverse=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at re.c:1861:12 [artificial]
    frame ruby#11: 0x0000000100230b90 ruby`rb_pat_search0(pat=<unavailable>, str=<unavailable>, pos=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at string.c:6619:16 [artificial]
    frame ruby#12: 0x00000001002287f4 ruby`rb_str_sub_bang [inlined] rb_pat_search(pat=4748462304, str=4748451168, pos=0, set_backref_str=1) at string.c:6626:12
    frame ruby#13: 0x00000001002287dc ruby`rb_str_sub_bang(argc=1, argv=0x00000001381280d0, str=4748451168) at string.c:6668:11
    frame ruby#14: 0x000000010022826c ruby`rb_str_sub
```

You can reproduce this by running:
```
RUBY_TESTOPTS="--name=/test_str_capitalize/" make test-all TESTS=test/ruby/test_m17n.comb
```

However, you need to run it with multiple ractors at once.

Co-authored-by: jhawthorn <[email protected]>

In commit d42b9ff, an optimization was introduced that can speed up
Regexp#match by 15% when it matches with strings of different encodings.
This optimization, however, does not work across ractors. To fix this,
we only use the optimization if no ractors have been started. In the
future, we could use atomics for the reference counting if we find it's
needed and if it's more performant.

The backtrace of the misbehaving native thread:

```
  * frame #0: 0x0000000189c94388 libsystem_kernel.dylib`__pthread_kill + 8
    frame #1: 0x0000000189ccd88c libsystem_pthread.dylib`pthread_kill + 296
    frame #2: 0x0000000189bd6c60 libsystem_c.dylib`abort + 124
    frame #3: 0x0000000189adb174 libsystem_malloc.dylib`malloc_vreport + 892
    frame #4: 0x0000000189adec90 libsystem_malloc.dylib`malloc_report + 64
    frame #5: 0x0000000189ae321c libsystem_malloc.dylib`___BUG_IN_CLIENT_OF_LIBMALLOC_POINTER_BEING_FREED_WAS_NOT_ALLOCATED + 32
    frame #6: 0x00000001001c3be4 ruby`onig_free_body(reg=0x000000012d84b660) at regcomp.c:5663:5
    frame #7: 0x00000001001ba828 ruby`rb_reg_prepare_re(re=4748462304, str=4748451168) at re.c:1680:13
    frame #8: 0x00000001001bac58 ruby`rb_reg_onig_match(re=4748462304, str=4748451168, match=(ruby`reg_onig_search [inlined] rbimpl_RB_TYPE_P_fastpath at value_type.h:349:14
ruby`reg_onig_search [inlined] rbimpl_rstring_getmem at rstring.h:391:5
ruby`reg_onig_search at re.c:1781:5), args=0x000000013824b168, regs=0x000000013824b150) at re.c:1708:20
    frame #9: 0x00000001001baefc ruby`rb_reg_search_set_match(re=4748462304, str=4748451168, pos=<unavailable>, reverse=0, set_backref_str=1, set_match=0x0000000000000000) at re.c:1809:27
    frame #10: 0x00000001001bae80 ruby`rb_reg_search0(re=<unavailable>, str=<unavailable>, pos=<unavailable>, reverse=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at re.c:1861:12 [artificial]
    frame #11: 0x0000000100230b90 ruby`rb_pat_search0(pat=<unavailable>, str=<unavailable>, pos=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at string.c:6619:16 [artificial]
    frame #12: 0x00000001002287f4 ruby`rb_str_sub_bang [inlined] rb_pat_search(pat=4748462304, str=4748451168, pos=0, set_backref_str=1) at string.c:6626:12
    frame #13: 0x00000001002287dc ruby`rb_str_sub_bang(argc=1, argv=0x00000001381280d0, str=4748451168) at string.c:6668:11
    frame #14: 0x000000010022826c ruby`rb_str_sub
```

You can reproduce this by running:
```
RUBY_TESTOPTS="--name=/test_str_capitalize/" make test-all TESTS=test/ruby/test_m17n.comb
```

However, you need to run it with multiple ractors at once.

Co-authored-by: jhawthorn <[email protected]>

In commit d42b9ff, an optimization was introduced that can speed up
Regexp#match by 15% when it matches with strings of different encodings.
This optimization, however, does not work across ractors. To fix this,
we only use the optimization if no ractors have been started. In the
future, we could use atomics for the reference counting if we find it's
needed and if it's more performant.

The backtrace of the misbehaving native thread:

```
  * frame #0: 0x0000000189c94388 libsystem_kernel.dylib`__pthread_kill + 8
    frame ruby#1: 0x0000000189ccd88c libsystem_pthread.dylib`pthread_kill + 296
    frame ruby#2: 0x0000000189bd6c60 libsystem_c.dylib`abort + 124
    frame ruby#3: 0x0000000189adb174 libsystem_malloc.dylib`malloc_vreport + 892
    frame ruby#4: 0x0000000189adec90 libsystem_malloc.dylib`malloc_report + 64
    frame ruby#5: 0x0000000189ae321c libsystem_malloc.dylib`___BUG_IN_CLIENT_OF_LIBMALLOC_POINTER_BEING_FREED_WAS_NOT_ALLOCATED + 32
    frame ruby#6: 0x00000001001c3be4 ruby`onig_free_body(reg=0x000000012d84b660) at regcomp.c:5663:5
    frame ruby#7: 0x00000001001ba828 ruby`rb_reg_prepare_re(re=4748462304, str=4748451168) at re.c:1680:13
    frame ruby#8: 0x00000001001bac58 ruby`rb_reg_onig_match(re=4748462304, str=4748451168, match=(ruby`reg_onig_search [inlined] rbimpl_RB_TYPE_P_fastpath at value_type.h:349:14
ruby`reg_onig_search [inlined] rbimpl_rstring_getmem at rstring.h:391:5
ruby`reg_onig_search at re.c:1781:5), args=0x000000013824b168, regs=0x000000013824b150) at re.c:1708:20
    frame ruby#9: 0x00000001001baefc ruby`rb_reg_search_set_match(re=4748462304, str=4748451168, pos=<unavailable>, reverse=0, set_backref_str=1, set_match=0x0000000000000000) at re.c:1809:27
    frame ruby#10: 0x00000001001bae80 ruby`rb_reg_search0(re=<unavailable>, str=<unavailable>, pos=<unavailable>, reverse=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at re.c:1861:12 [artificial]
    frame ruby#11: 0x0000000100230b90 ruby`rb_pat_search0(pat=<unavailable>, str=<unavailable>, pos=<unavailable>, set_backref_str=<unavailable>, match=<unavailable>) at string.c:6619:16 [artificial]
    frame ruby#12: 0x00000001002287f4 ruby`rb_str_sub_bang [inlined] rb_pat_search(pat=4748462304, str=4748451168, pos=0, set_backref_str=1) at string.c:6626:12
    frame ruby#13: 0x00000001002287dc ruby`rb_str_sub_bang(argc=1, argv=0x00000001381280d0, str=4748451168) at string.c:6668:11
    frame ruby#14: 0x000000010022826c ruby`rb_str_sub
```

You can reproduce this by running:
```
RUBY_TESTOPTS="--name=/test_str_capitalize/" make test-all TESTS=test/ruby/test_m17n.comb
```

However, you need to run it with multiple ractors at once.

Co-authored-by: jhawthorn <[email protected]>

`name` is used via `RSTRING_PTR` within rb_str_catf, which may allocate
and thus potentially trigger GC. Although `name` is still referenced
by a local variable, the compiler might optimize away the reference
before the GC sees it, especially under aggressive optimization or when
debugging tools like ASAN are used.

This patch adds an explicit `RB_GC_GUARD` to ensure `name` is kept alive
until after the last use.

While it's not certain this is the root cause of the following observed
use-after-poison ASAN error, I believe this fix is indeed needed and
hopefully a likely candidate for preventing the error.

```
==1960369==ERROR: AddressSanitizer: use-after-poison on address 0x7ec6a00f1d88 at pc 0x5fb5bcafcf2e bp 0x7ffcc1178cb0 sp 0x7ffcc1178470
READ of size 61 at 0x7ec6a00f1d88 thread T0
    #0 0x5fb5bcafcf2d in __asan_memcpy (/tmp/ruby/build/trunk_asan/ruby+0x204f2d) (BuildId: 6d92c84a27b87cfd253c38eeb552593f215ffb3d)
    ruby#1 0x5fb5bcde1fa5 in memcpy /usr/include/x86_64-linux-gnu/bits/string_fortified.h:29:10
    ruby#2 0x5fb5bcde1fa5 in ruby_nonempty_memcpy /tmp/ruby/src/trunk_asan/include/ruby/internal/memory.h:758:16
    ruby#3 0x5fb5bcde1fa5 in ruby__sfvwrite /tmp/ruby/src/trunk_asan/sprintf.c:1083:9
    ruby#4 0x5fb5bcde1521 in BSD__sprint /tmp/ruby/src/trunk_asan/vsnprintf.c:318:8
    ruby#5 0x5fb5bcde0fbc in BSD_vfprintf /tmp/ruby/src/trunk_asan/vsnprintf.c:1215:3
    ruby#6 0x5fb5bcdde4b1 in ruby_vsprintf0 /tmp/ruby/src/trunk_asan/sprintf.c:1164:5
    ruby#7 0x5fb5bcddd648 in rb_str_vcatf /tmp/ruby/src/trunk_asan/sprintf.c:1234:5
    ruby#8 0x5fb5bcddd648 in rb_str_catf /tmp/ruby/src/trunk_asan/sprintf.c:1245:11
    ruby#9 0x5fb5bcf97c67 in location_format /tmp/ruby/src/trunk_asan/vm_backtrace.c:462:9
    ruby#10 0x5fb5bcf97c67 in location_to_str /tmp/ruby/src/trunk_asan/vm_backtrace.c:493:12
    ruby#11 0x5fb5bcf90a37 in location_to_str_dmyarg /tmp/ruby/src/trunk_asan/vm_backtrace.c:795:12
    ruby#12 0x5fb5bcf90a37 in backtrace_collect /tmp/ruby/src/trunk_asan/vm_backtrace.c:786:28
    ruby#13 0x5fb5bcf90a37 in backtrace_to_str_ary /tmp/ruby/src/trunk_asan/vm_backtrace.c:804:9
    ruby#14 0x5fb5bcf90a37 in rb_backtrace_to_str_ary /tmp/ruby/src/trunk_asan/vm_backtrace.c:816:9
    ruby#15 0x5fb5bd335b25 in exc_backtrace /tmp/ruby/src/trunk_asan/error.c:1904:15
    ruby#16 0x5fb5bd335b25 in rb_get_backtrace /tmp/ruby/src/trunk_asan/error.c:1924:16
```
https://ci.rvm.jp/results/trunk_asan@ruby-sp1/5810304

`name` is used via `RSTRING_PTR` within rb_str_catf, which may allocate
and thus potentially trigger GC. Although `name` is still referenced
by a local variable, the compiler might optimize away the reference
before the GC sees it, especially under aggressive optimization or when
debugging tools like ASAN are used.

This patch adds an explicit `RB_GC_GUARD` to ensure `name` is kept alive
until after the last use.

While it's not certain this is the root cause of the following observed
use-after-poison ASAN error, I believe this fix is indeed needed and
hopefully a likely candidate for preventing the error.

```
==1960369==ERROR: AddressSanitizer: use-after-poison on address 0x7ec6a00f1d88 at pc 0x5fb5bcafcf2e bp 0x7ffcc1178cb0 sp 0x7ffcc1178470
READ of size 61 at 0x7ec6a00f1d88 thread T0
    #0 0x5fb5bcafcf2d in __asan_memcpy (/tmp/ruby/build/trunk_asan/ruby+0x204f2d) (BuildId: 6d92c84a27b87cfd253c38eeb552593f215ffb3d)
    #1 0x5fb5bcde1fa5 in memcpy /usr/include/x86_64-linux-gnu/bits/string_fortified.h:29:10
    #2 0x5fb5bcde1fa5 in ruby_nonempty_memcpy /tmp/ruby/src/trunk_asan/include/ruby/internal/memory.h:758:16
    #3 0x5fb5bcde1fa5 in ruby__sfvwrite /tmp/ruby/src/trunk_asan/sprintf.c:1083:9
    #4 0x5fb5bcde1521 in BSD__sprint /tmp/ruby/src/trunk_asan/vsnprintf.c:318:8
    #5 0x5fb5bcde0fbc in BSD_vfprintf /tmp/ruby/src/trunk_asan/vsnprintf.c:1215:3
    #6 0x5fb5bcdde4b1 in ruby_vsprintf0 /tmp/ruby/src/trunk_asan/sprintf.c:1164:5
    #7 0x5fb5bcddd648 in rb_str_vcatf /tmp/ruby/src/trunk_asan/sprintf.c:1234:5
    #8 0x5fb5bcddd648 in rb_str_catf /tmp/ruby/src/trunk_asan/sprintf.c:1245:11
    #9 0x5fb5bcf97c67 in location_format /tmp/ruby/src/trunk_asan/vm_backtrace.c:462:9
    #10 0x5fb5bcf97c67 in location_to_str /tmp/ruby/src/trunk_asan/vm_backtrace.c:493:12
    #11 0x5fb5bcf90a37 in location_to_str_dmyarg /tmp/ruby/src/trunk_asan/vm_backtrace.c:795:12
    #12 0x5fb5bcf90a37 in backtrace_collect /tmp/ruby/src/trunk_asan/vm_backtrace.c:786:28
    #13 0x5fb5bcf90a37 in backtrace_to_str_ary /tmp/ruby/src/trunk_asan/vm_backtrace.c:804:9
    #14 0x5fb5bcf90a37 in rb_backtrace_to_str_ary /tmp/ruby/src/trunk_asan/vm_backtrace.c:816:9
    #15 0x5fb5bd335b25 in exc_backtrace /tmp/ruby/src/trunk_asan/error.c:1904:15
    #16 0x5fb5bd335b25 in rb_get_backtrace /tmp/ruby/src/trunk_asan/error.c:1924:16
```
https://ci.rvm.jp/results/trunk_asan@ruby-sp1/5810304

If we malloc when the current Ractor is locked, we can deadlock because
GC requires VM lock and Ractor barrier. If another Ractor is waiting on
this Ractor lock, then it will deadlock because the other Ractor will
never join the barrier.

For example, this script deadlocks:

    r = Ractor.new do
      loop do
        Ractor::Port.new
      end
    end

    100000.times do |i|
      r.send(nil)
      puts i
    end

On debug builds, it fails with this assertion error:

    vm_sync.c:75: Assertion Failed: vm_lock_enter:cr->sync.locked_by != rb_ractor_self(cr)

On non-debug builds, we can see that it deadlocks in the debugger:

    Main Ractor:
    frame ruby#3: 0x000000010021fdc4 miniruby`rb_native_mutex_lock(lock=<unavailable>) at thread_pthread.c:115:14
    frame ruby#4: 0x0000000100193eb8 miniruby`ractor_send0 [inlined] ractor_lock(r=<unavailable>, file=<unavailable>, line=1180) at ractor.c:73:5
    frame ruby#5: 0x0000000100193eb0 miniruby`ractor_send0 [inlined] ractor_send_basket(ec=<unavailable>, rp=0x0000000131092840, b=0x000000011c63de80, raise_on_error=true) at ractor_sync.c:1180:5
    frame ruby#6: 0x0000000100193eac miniruby`ractor_send0(ec=<unavailable>, rp=0x0000000131092840, obj=4, move=<unavailable>, raise_on_error=true) at ractor_sync.c:1211:5

    Second Ractor:
    frame ruby#2: 0x00000001002208d0 miniruby`rb_ractor_sched_barrier_start [inlined] rb_native_cond_wait(cond=<unavailable>, mutex=<unavailable>) at thread_pthread.c:221:13
    frame ruby#3: 0x00000001002208cc miniruby`rb_ractor_sched_barrier_start(vm=0x000000013180d600, cr=0x0000000131093460) at thread_pthread.c:1438:13
    frame ruby#4: 0x000000010028a328 miniruby`rb_vm_barrier at vm_sync.c:262:13 [artificial]
    frame ruby#5: 0x00000001000dfa6c miniruby`gc_start [inlined] rb_gc_vm_barrier at gc.c:179:5
    frame ruby#6: 0x00000001000dfa68 miniruby`gc_start [inlined] gc_enter(objspace=0x000000013180fc00, event=gc_enter_event_start, lock_lev=<unavailable>) at default.c:6636:9
    frame ruby#7: 0x00000001000dfa48 miniruby`gc_start(objspace=0x000000013180fc00, reason=<unavailable>) at default.c:6361:5
    frame ruby#8: 0x00000001000e3fd8 miniruby`objspace_malloc_increase_body [inlined] garbage_collect(objspace=0x000000013180fc00, reason=512) at default.c:6341:15
    frame ruby#9: 0x00000001000e3fa4 miniruby`objspace_malloc_increase_body [inlined] garbage_collect_with_gvl(objspace=0x000000013180fc00, reason=512) at default.c:6741:16
    frame ruby#10: 0x00000001000e3f88 miniruby`objspace_malloc_increase_body(objspace=0x000000013180fc00, mem=<unavailable>, new_size=<unavailable>, old_size=<unavailable>, type=<unavailable>) at default.c:8007:13
    frame ruby#11: 0x00000001000e3c44 miniruby`rb_gc_impl_malloc [inlined] objspace_malloc_fixup(objspace=0x000000013180fc00, mem=0x000000011c700000, size=12582912) at default.c:8085:5
    frame ruby#12: 0x00000001000e3c30 miniruby`rb_gc_impl_malloc(objspace_ptr=0x000000013180fc00, size=12582912) at default.c:8182:12
    frame ruby#13: 0x00000001000d4584 miniruby`ruby_xmalloc [inlined] ruby_xmalloc_body(size=<unavailable>) at gc.c:5128:12
    frame ruby#14: 0x00000001000d4568 miniruby`ruby_xmalloc(size=<unavailable>) at gc.c:5118:34
    frame ruby#15: 0x00000001001eb184 miniruby`rb_st_init_existing_table_with_size(tab=0x000000011c2b4b40, type=<unavailable>, size=<unavailable>) at st.c:559:39
    frame ruby#16: 0x00000001001ebc74 miniruby`rebuild_table_if_necessary [inlined] rb_st_init_table_with_size(type=0x00000001004f4a78, size=524287) at st.c:585:5
    frame ruby#17: 0x00000001001ebc5c miniruby`rebuild_table_if_necessary [inlined] rebuild_table(tab=0x000000013108e2f0) at st.c:753:19
    frame ruby#18: 0x00000001001ebbfc miniruby`rebuild_table_if_necessary(tab=0x000000013108e2f0) at st.c:1125:9
    frame ruby#19: 0x00000001001eba08 miniruby`rb_st_insert(tab=0x000000013108e2f0, key=262144, value=4767566624) at st.c:1143:5
    frame #20: 0x0000000100194b84 miniruby`ractor_port_initialzie [inlined] ractor_add_port(r=0x0000000131093460, id=262144) at ractor_sync.c:399:9
    frame ruby#21: 0x0000000100194b58 miniruby`ractor_port_initialzie [inlined] ractor_port_init(rpv=4750065560, r=0x0000000131093460) at ractor_sync.c:87:5
    frame ruby#22: 0x0000000100194b34 miniruby`ractor_port_initialzie(self=4750065560) at ractor_sync.c:103:12

If we malloc when the current Ractor is locked, we can deadlock because
GC requires VM lock and Ractor barrier. If another Ractor is waiting on
this Ractor lock, then it will deadlock because the other Ractor will
never join the barrier.

For example, this script deadlocks:

    r = Ractor.new do
      loop do
        Ractor::Port.new
      end
    end

    100000.times do |i|
      r.send(nil)
      puts i
    end

On debug builds, it fails with this assertion error:

    vm_sync.c:75: Assertion Failed: vm_lock_enter:cr->sync.locked_by != rb_ractor_self(cr)

On non-debug builds, we can see that it deadlocks in the debugger:

    Main Ractor:
    frame ruby#3: 0x000000010021fdc4 miniruby`rb_native_mutex_lock(lock=<unavailable>) at thread_pthread.c:115:14
    frame ruby#4: 0x0000000100193eb8 miniruby`ractor_send0 [inlined] ractor_lock(r=<unavailable>, file=<unavailable>, line=1180) at ractor.c:73:5
    frame ruby#5: 0x0000000100193eb0 miniruby`ractor_send0 [inlined] ractor_send_basket(ec=<unavailable>, rp=0x0000000131092840, b=0x000000011c63de80, raise_on_error=true) at ractor_sync.c:1180:5
    frame ruby#6: 0x0000000100193eac miniruby`ractor_send0(ec=<unavailable>, rp=0x0000000131092840, obj=4, move=<unavailable>, raise_on_error=true) at ractor_sync.c:1211:5

    Second Ractor:
    frame ruby#2: 0x00000001002208d0 miniruby`rb_ractor_sched_barrier_start [inlined] rb_native_cond_wait(cond=<unavailable>, mutex=<unavailable>) at thread_pthread.c:221:13
    frame ruby#3: 0x00000001002208cc miniruby`rb_ractor_sched_barrier_start(vm=0x000000013180d600, cr=0x0000000131093460) at thread_pthread.c:1438:13
    frame ruby#4: 0x000000010028a328 miniruby`rb_vm_barrier at vm_sync.c:262:13 [artificial]
    frame ruby#5: 0x00000001000dfa6c miniruby`gc_start [inlined] rb_gc_vm_barrier at gc.c:179:5
    frame ruby#6: 0x00000001000dfa68 miniruby`gc_start [inlined] gc_enter(objspace=0x000000013180fc00, event=gc_enter_event_start, lock_lev=<unavailable>) at default.c:6636:9
    frame ruby#7: 0x00000001000dfa48 miniruby`gc_start(objspace=0x000000013180fc00, reason=<unavailable>) at default.c:6361:5
    frame ruby#8: 0x00000001000e3fd8 miniruby`objspace_malloc_increase_body [inlined] garbage_collect(objspace=0x000000013180fc00, reason=512) at default.c:6341:15
    frame ruby#9: 0x00000001000e3fa4 miniruby`objspace_malloc_increase_body [inlined] garbage_collect_with_gvl(objspace=0x000000013180fc00, reason=512) at default.c:6741:16
    frame ruby#10: 0x00000001000e3f88 miniruby`objspace_malloc_increase_body(objspace=0x000000013180fc00, mem=<unavailable>, new_size=<unavailable>, old_size=<unavailable>, type=<unavailable>) at default.c:8007:13
    frame ruby#11: 0x00000001000e3c44 miniruby`rb_gc_impl_malloc [inlined] objspace_malloc_fixup(objspace=0x000000013180fc00, mem=0x000000011c700000, size=12582912) at default.c:8085:5
    frame ruby#12: 0x00000001000e3c30 miniruby`rb_gc_impl_malloc(objspace_ptr=0x000000013180fc00, size=12582912) at default.c:8182:12
    frame ruby#13: 0x00000001000d4584 miniruby`ruby_xmalloc [inlined] ruby_xmalloc_body(size=<unavailable>) at gc.c:5128:12
    frame ruby#14: 0x00000001000d4568 miniruby`ruby_xmalloc(size=<unavailable>) at gc.c:5118:34
    frame ruby#15: 0x00000001001eb184 miniruby`rb_st_init_existing_table_with_size(tab=0x000000011c2b4b40, type=<unavailable>, size=<unavailable>) at st.c:559:39
    frame ruby#16: 0x00000001001ebc74 miniruby`rebuild_table_if_necessary [inlined] rb_st_init_table_with_size(type=0x00000001004f4a78, size=524287) at st.c:585:5
    frame ruby#17: 0x00000001001ebc5c miniruby`rebuild_table_if_necessary [inlined] rebuild_table(tab=0x000000013108e2f0) at st.c:753:19
    frame ruby#18: 0x00000001001ebbfc miniruby`rebuild_table_if_necessary(tab=0x000000013108e2f0) at st.c:1125:9
    frame ruby#19: 0x00000001001eba08 miniruby`rb_st_insert(tab=0x000000013108e2f0, key=262144, value=4767566624) at st.c:1143:5
    frame #20: 0x0000000100194b84 miniruby`ractor_port_initialzie [inlined] ractor_add_port(r=0x0000000131093460, id=262144) at ractor_sync.c:399:9
    frame ruby#21: 0x0000000100194b58 miniruby`ractor_port_initialzie [inlined] ractor_port_init(rpv=4750065560, r=0x0000000131093460) at ractor_sync.c:87:5
    frame ruby#22: 0x0000000100194b34 miniruby`ractor_port_initialzie(self=4750065560) at ractor_sync.c:103:12

If we malloc when the current Ractor is locked, we can deadlock because
GC requires VM lock and Ractor barrier. If another Ractor is waiting on
this Ractor lock, then it will deadlock because the other Ractor will
never join the barrier.

For example, this script deadlocks:

    r = Ractor.new do
      loop do
        Ractor::Port.new
      end
    end

    100000.times do |i|
      r.send(nil)
      puts i
    end

On debug builds, it fails with this assertion error:

    vm_sync.c:75: Assertion Failed: vm_lock_enter:cr->sync.locked_by != rb_ractor_self(cr)

On non-debug builds, we can see that it deadlocks in the debugger:

    Main Ractor:
    frame #3: 0x000000010021fdc4 miniruby`rb_native_mutex_lock(lock=<unavailable>) at thread_pthread.c:115:14
    frame #4: 0x0000000100193eb8 miniruby`ractor_send0 [inlined] ractor_lock(r=<unavailable>, file=<unavailable>, line=1180) at ractor.c:73:5
    frame #5: 0x0000000100193eb0 miniruby`ractor_send0 [inlined] ractor_send_basket(ec=<unavailable>, rp=0x0000000131092840, b=0x000000011c63de80, raise_on_error=true) at ractor_sync.c:1180:5
    frame #6: 0x0000000100193eac miniruby`ractor_send0(ec=<unavailable>, rp=0x0000000131092840, obj=4, move=<unavailable>, raise_on_error=true) at ractor_sync.c:1211:5

    Second Ractor:
    frame #2: 0x00000001002208d0 miniruby`rb_ractor_sched_barrier_start [inlined] rb_native_cond_wait(cond=<unavailable>, mutex=<unavailable>) at thread_pthread.c:221:13
    frame #3: 0x00000001002208cc miniruby`rb_ractor_sched_barrier_start(vm=0x000000013180d600, cr=0x0000000131093460) at thread_pthread.c:1438:13
    frame #4: 0x000000010028a328 miniruby`rb_vm_barrier at vm_sync.c:262:13 [artificial]
    frame #5: 0x00000001000dfa6c miniruby`gc_start [inlined] rb_gc_vm_barrier at gc.c:179:5
    frame #6: 0x00000001000dfa68 miniruby`gc_start [inlined] gc_enter(objspace=0x000000013180fc00, event=gc_enter_event_start, lock_lev=<unavailable>) at default.c:6636:9
    frame #7: 0x00000001000dfa48 miniruby`gc_start(objspace=0x000000013180fc00, reason=<unavailable>) at default.c:6361:5
    frame #8: 0x00000001000e3fd8 miniruby`objspace_malloc_increase_body [inlined] garbage_collect(objspace=0x000000013180fc00, reason=512) at default.c:6341:15
    frame #9: 0x00000001000e3fa4 miniruby`objspace_malloc_increase_body [inlined] garbage_collect_with_gvl(objspace=0x000000013180fc00, reason=512) at default.c:6741:16
    frame #10: 0x00000001000e3f88 miniruby`objspace_malloc_increase_body(objspace=0x000000013180fc00, mem=<unavailable>, new_size=<unavailable>, old_size=<unavailable>, type=<unavailable>) at default.c:8007:13
    frame #11: 0x00000001000e3c44 miniruby`rb_gc_impl_malloc [inlined] objspace_malloc_fixup(objspace=0x000000013180fc00, mem=0x000000011c700000, size=12582912) at default.c:8085:5
    frame #12: 0x00000001000e3c30 miniruby`rb_gc_impl_malloc(objspace_ptr=0x000000013180fc00, size=12582912) at default.c:8182:12
    frame #13: 0x00000001000d4584 miniruby`ruby_xmalloc [inlined] ruby_xmalloc_body(size=<unavailable>) at gc.c:5128:12
    frame #14: 0x00000001000d4568 miniruby`ruby_xmalloc(size=<unavailable>) at gc.c:5118:34
    frame #15: 0x00000001001eb184 miniruby`rb_st_init_existing_table_with_size(tab=0x000000011c2b4b40, type=<unavailable>, size=<unavailable>) at st.c:559:39
    frame #16: 0x00000001001ebc74 miniruby`rebuild_table_if_necessary [inlined] rb_st_init_table_with_size(type=0x00000001004f4a78, size=524287) at st.c:585:5
    frame #17: 0x00000001001ebc5c miniruby`rebuild_table_if_necessary [inlined] rebuild_table(tab=0x000000013108e2f0) at st.c:753:19
    frame #18: 0x00000001001ebbfc miniruby`rebuild_table_if_necessary(tab=0x000000013108e2f0) at st.c:1125:9
    frame #19: 0x00000001001eba08 miniruby`rb_st_insert(tab=0x000000013108e2f0, key=262144, value=4767566624) at st.c:1143:5
    frame #20: 0x0000000100194b84 miniruby`ractor_port_initialzie [inlined] ractor_add_port(r=0x0000000131093460, id=262144) at ractor_sync.c:399:9
    frame #21: 0x0000000100194b58 miniruby`ractor_port_initialzie [inlined] ractor_port_init(rpv=4750065560, r=0x0000000131093460) at ractor_sync.c:87:5
    frame #22: 0x0000000100194b34 miniruby`ractor_port_initialzie(self=4750065560) at ractor_sync.c:103:12

When RUBYOPT is invalid, it raises an error which causes moreswitches
to leak memory. It can be seen when building with LSAN enabled:

    $ RUBY_FREE_AT_EXIT=1 RUBYOPT=f ruby
    ruby: invalid option -f  (-h will show valid options) (RuntimeError)

    Direct leak of 16 byte(s) in 1 object(s) allocated from:
        #0 0x618cef8efa23 in malloc (miniruby+0x64a23)
        #1 0x618cefa0e8d8 in rb_gc_impl_malloc gc/default/default.c:8182:5
        ruby#2 0x618cef9f7f01 in ruby_xmalloc2_body gc.c:5182:12
        ruby#3 0x618cef9f7eac in ruby_xmalloc2 gc.c:5176:34
        ruby#4 0x618cefb547b2 in moreswitches ruby.c:919:18
        ruby#5 0x618cefb526fe in process_options ruby.c:2350:9
        ruby#6 0x618cefb524ac in ruby_process_options ruby.c:3202:12
        ruby#7 0x618cef9dc11f in ruby_options eval.c:119:16
        ruby#8 0x618cef8f2fb5 in rb_main main.c:42:26
        ruby#9 0x618cef8f2f59 in main main.c:62:12

When RUBYOPT is invalid, it raises an error which causes moreswitches
to leak memory. It can be seen when building with LSAN enabled:

    $ RUBY_FREE_AT_EXIT=1 RUBYOPT=f ruby
    ruby: invalid option -f  (-h will show valid options) (RuntimeError)

    Direct leak of 16 byte(s) in 1 object(s) allocated from:
        #0 0x618cef8efa23 in malloc (miniruby+0x64a23)
        #1 0x618cefa0e8d8 in rb_gc_impl_malloc gc/default/default.c:8182:5
        ruby#2 0x618cef9f7f01 in ruby_xmalloc2_body gc.c:5182:12
        ruby#3 0x618cef9f7eac in ruby_xmalloc2 gc.c:5176:34
        ruby#4 0x618cefb547b2 in moreswitches ruby.c:919:18
        ruby#5 0x618cefb526fe in process_options ruby.c:2350:9
        ruby#6 0x618cefb524ac in ruby_process_options ruby.c:3202:12
        ruby#7 0x618cef9dc11f in ruby_options eval.c:119:16
        ruby#8 0x618cef8f2fb5 in rb_main main.c:42:26
        ruby#9 0x618cef8f2f59 in main main.c:62:12

When RUBYOPT is invalid, it raises an error which causes moreswitches
to leak memory. It can be seen when building with LSAN enabled:

    $ RUBY_FREE_AT_EXIT=1 RUBYOPT=f ruby
    ruby: invalid option -f  (-h will show valid options) (RuntimeError)

    Direct leak of 16 byte(s) in 1 object(s) allocated from:
        #0 0x618cef8efa23 in malloc (miniruby+0x64a23)
        #1 0x618cefa0e8d8 in rb_gc_impl_malloc gc/default/default.c:8182:5
        #2 0x618cef9f7f01 in ruby_xmalloc2_body gc.c:5182:12
        #3 0x618cef9f7eac in ruby_xmalloc2 gc.c:5176:34
        #4 0x618cefb547b2 in moreswitches ruby.c:919:18
        #5 0x618cefb526fe in process_options ruby.c:2350:9
        #6 0x618cefb524ac in ruby_process_options ruby.c:3202:12
        #7 0x618cef9dc11f in ruby_options eval.c:119:16
        #8 0x618cef8f2fb5 in rb_main main.c:42:26
        #9 0x618cef8f2f59 in main main.c:62:12

We were seeing errors like:

* thread ruby#8, stop reason = EXC_BAD_ACCESS (code=1, address=0x803)
  * frame #0: 0x00000001001fe944 ruby`rb_st_lookup(tab=0x00000000000007fb, key=1, value=0x00000001305b7490) at st.c:1066:22
    frame ruby#1: 0x000000010002d658 ruby`remove_class_from_subclasses [inlined] class_get_subclasses_for_ns(tbl=0x00000000000007fb, ns_id=1) at class.c:604:9
    frame ruby#2: 0x000000010002d650 ruby`remove_class_from_subclasses(tbl=0x00000000000007fb, ns_id=1, klass=4754039232) at class.c:620:34
    frame ruby#3: 0x000000010002c8a8 ruby`rb_class_classext_free_subclasses(ext=0x000000011b5ce1d8, klass=4754039232, replacing=<unavailable>) at class.c:700:9
    frame ruby#4: 0x000000010002c760 ruby`rb_class_classext_free(klass=4754039232, ext=0x000000011b5ce1d8, is_prime=true) at class.c:105:5
    frame ruby#5: 0x00000001000e770c ruby`classext_free(ext=<unavailable>, is_prime=<unavailable>, namespace=<unavailable>, arg=<unavailable>) at gc.c:1231:5 [artificial]
    frame ruby#6: 0x000000010002d178 ruby`rb_class_classext_foreach(klass=<unavailable>, func=(ruby`classext_free at gc.c:1228), arg=0x00000001305b75c0) at class.c:518:5
    frame ruby#7: 0x00000001000e745c ruby`rb_gc_obj_free(objspace=0x000000012500c400, obj=4754039232) at gc.c:1282:9
    frame ruby#8: 0x00000001000e70d4 ruby`gc_sweep_plane(objspace=0x000000012500c400, heap=<unavailable>, p=4754039232, bitset=4095, ctx=0x00000001305b76e8) at default.c:3482:21
    frame ruby#9: 0x00000001000e6e9c ruby`gc_sweep_page(objspace=0x000000012500c400, heap=0x000000012500c540, ctx=0x00000001305b76e8) at default.c:3567:13
    frame ruby#10: 0x00000001000e51d0 ruby`gc_sweep_step(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:3848:9
    frame ruby#11: 0x00000001000e1880 ruby`gc_continue [inlined] gc_sweep_continue(objspace=0x000000012500c400, sweep_heap=0x000000012500c540) at default.c:3931:13
    frame ruby#12: 0x00000001000e1754 ruby`gc_continue(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2037:9
    frame ruby#13: 0x00000001000e10bc ruby`newobj_cache_miss [inlined] heap_prepare(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2056:5
    frame ruby#14: 0x00000001000e1074 ruby`newobj_cache_miss [inlined] heap_next_free_page(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2280:9
    frame ruby#15: 0x00000001000e106c ruby`newobj_cache_miss(objspace=0x000000012500c400, cache=0x0000600001b00300, heap_idx=2, vm_locked=false) at default.c:2387:38
    frame ruby#16: 0x00000001000e0d28 ruby`newobj_alloc(objspace=<unavailable>, cache=<unavailable>, heap_idx=<unavailable>, vm_locked=<unavailable>) at default.c:2411:15 [artificial]
    frame ruby#17: 0x00000001000d7214 ruby`newobj_of [inlined] rb_gc_impl_new_obj(objspace_ptr=<unavailable>, cache_ptr=<unavailable>, klass=<unavailable>, flags=<unavailable>, wb_protected=<unavailable>, alloc_size=<unavailable>) at default.c:2490:15
    frame ruby#18: 0x00000001000d719c ruby`newobj_of(cr=<unavailable>, klass=4313971728, flags=258, wb_protected=<unavailable>, size=<unavailable>) at gc.c:995:17
    frame ruby#19: 0x00000001000d73ec ruby`rb_wb_protected_newobj_of(ec=<unavailable>, klass=<unavailable>, flags=<unavailable>, size=<unavailable>) at gc.c:1044:12 [artificial]
    frame #20: 0x0000000100032d34 ruby`class_alloc0(type=<unavailable>, klass=4313971728, namespaceable=<unavailable>) at class.c:803:5

We were seeing errors like:

```
* thread ruby#8, stop reason = EXC_BAD_ACCESS (code=1, address=0x803)
  * frame #0: 0x00000001001fe944 ruby`rb_st_lookup(tab=0x00000000000007fb, key=1, value=0x00000001305b7490) at st.c:1066:22
    frame ruby#1: 0x000000010002d658 ruby`remove_class_from_subclasses [inlined] class_get_subclasses_for_ns(tbl=0x00000000000007fb, ns_id=1) at class.c:604:9
    frame ruby#2: 0x000000010002d650 ruby`remove_class_from_subclasses(tbl=0x00000000000007fb, ns_id=1, klass=4754039232) at class.c:620:34
    frame ruby#3: 0x000000010002c8a8 ruby`rb_class_classext_free_subclasses(ext=0x000000011b5ce1d8, klass=4754039232, replacing=<unavailable>) at class.c:700:9
    frame ruby#4: 0x000000010002c760 ruby`rb_class_classext_free(klass=4754039232, ext=0x000000011b5ce1d8, is_prime=true) at class.c:105:5
    frame ruby#5: 0x00000001000e770c ruby`classext_free(ext=<unavailable>, is_prime=<unavailable>, namespace=<unavailable>, arg=<unavailable>) at gc.c:1231:5 [artificial]
    frame ruby#6: 0x000000010002d178 ruby`rb_class_classext_foreach(klass=<unavailable>, func=(ruby`classext_free at gc.c:1228), arg=0x00000001305b75c0) at class.c:518:5
    frame ruby#7: 0x00000001000e745c ruby`rb_gc_obj_free(objspace=0x000000012500c400, obj=4754039232) at gc.c:1282:9
    frame ruby#8: 0x00000001000e70d4 ruby`gc_sweep_plane(objspace=0x000000012500c400, heap=<unavailable>, p=4754039232, bitset=4095, ctx=0x00000001305b76e8) at default.c:3482:21
    frame ruby#9: 0x00000001000e6e9c ruby`gc_sweep_page(objspace=0x000000012500c400, heap=0x000000012500c540, ctx=0x00000001305b76e8) at default.c:3567:13
    frame ruby#10: 0x00000001000e51d0 ruby`gc_sweep_step(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:3848:9
    frame ruby#11: 0x00000001000e1880 ruby`gc_continue [inlined] gc_sweep_continue(objspace=0x000000012500c400, sweep_heap=0x000000012500c540) at default.c:3931:13
    frame ruby#12: 0x00000001000e1754 ruby`gc_continue(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2037:9
    frame ruby#13: 0x00000001000e10bc ruby`newobj_cache_miss [inlined] heap_prepare(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2056:5
    frame ruby#14: 0x00000001000e1074 ruby`newobj_cache_miss [inlined] heap_next_free_page(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2280:9
    frame ruby#15: 0x00000001000e106c ruby`newobj_cache_miss(objspace=0x000000012500c400, cache=0x0000600001b00300, heap_idx=2, vm_locked=false) at default.c:2387:38
    frame ruby#16: 0x00000001000e0d28 ruby`newobj_alloc(objspace=<unavailable>, cache=<unavailable>, heap_idx=<unavailable>, vm_locked=<unavailable>) at default.c:2411:15 [artificial]
    frame ruby#17: 0x00000001000d7214 ruby`newobj_of [inlined] rb_gc_impl_new_obj(objspace_ptr=<unavailable>, cache_ptr=<unavailable>, klass=<unavailable>, flags=<unavailable>, wb_protected=<unavailable>, alloc_size=<unavailable>) at default.c:2490:15
    frame ruby#18: 0x00000001000d719c ruby`newobj_of(cr=<unavailable>, klass=4313971728, flags=258, wb_protected=<unavailable>, size=<unavailable>) at gc.c:995:17
    frame ruby#19: 0x00000001000d73ec ruby`rb_wb_protected_newobj_of(ec=<unavailable>, klass=<unavailable>, flags=<unavailable>, size=<unavailable>) at gc.c:1044:12 [artificial]
    frame #20: 0x0000000100032d34 ruby`class_alloc0(type=<unavailable>, klass=4313971728, namespaceable=<unavailable>) at class.c:803:5
```

We were seeing errors like:

```
* thread #8, stop reason = EXC_BAD_ACCESS (code=1, address=0x803)
  * frame #0: 0x00000001001fe944 ruby`rb_st_lookup(tab=0x00000000000007fb, key=1, value=0x00000001305b7490) at st.c:1066:22
    frame #1: 0x000000010002d658 ruby`remove_class_from_subclasses [inlined] class_get_subclasses_for_ns(tbl=0x00000000000007fb, ns_id=1) at class.c:604:9
    frame #2: 0x000000010002d650 ruby`remove_class_from_subclasses(tbl=0x00000000000007fb, ns_id=1, klass=4754039232) at class.c:620:34
    frame #3: 0x000000010002c8a8 ruby`rb_class_classext_free_subclasses(ext=0x000000011b5ce1d8, klass=4754039232, replacing=<unavailable>) at class.c:700:9
    frame #4: 0x000000010002c760 ruby`rb_class_classext_free(klass=4754039232, ext=0x000000011b5ce1d8, is_prime=true) at class.c:105:5
    frame #5: 0x00000001000e770c ruby`classext_free(ext=<unavailable>, is_prime=<unavailable>, namespace=<unavailable>, arg=<unavailable>) at gc.c:1231:5 [artificial]
    frame #6: 0x000000010002d178 ruby`rb_class_classext_foreach(klass=<unavailable>, func=(ruby`classext_free at gc.c:1228), arg=0x00000001305b75c0) at class.c:518:5
    frame #7: 0x00000001000e745c ruby`rb_gc_obj_free(objspace=0x000000012500c400, obj=4754039232) at gc.c:1282:9
    frame #8: 0x00000001000e70d4 ruby`gc_sweep_plane(objspace=0x000000012500c400, heap=<unavailable>, p=4754039232, bitset=4095, ctx=0x00000001305b76e8) at default.c:3482:21
    frame #9: 0x00000001000e6e9c ruby`gc_sweep_page(objspace=0x000000012500c400, heap=0x000000012500c540, ctx=0x00000001305b76e8) at default.c:3567:13
    frame #10: 0x00000001000e51d0 ruby`gc_sweep_step(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:3848:9
    frame #11: 0x00000001000e1880 ruby`gc_continue [inlined] gc_sweep_continue(objspace=0x000000012500c400, sweep_heap=0x000000012500c540) at default.c:3931:13
    frame #12: 0x00000001000e1754 ruby`gc_continue(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2037:9
    frame #13: 0x00000001000e10bc ruby`newobj_cache_miss [inlined] heap_prepare(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2056:5
    frame #14: 0x00000001000e1074 ruby`newobj_cache_miss [inlined] heap_next_free_page(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2280:9
    frame #15: 0x00000001000e106c ruby`newobj_cache_miss(objspace=0x000000012500c400, cache=0x0000600001b00300, heap_idx=2, vm_locked=false) at default.c:2387:38
    frame #16: 0x00000001000e0d28 ruby`newobj_alloc(objspace=<unavailable>, cache=<unavailable>, heap_idx=<unavailable>, vm_locked=<unavailable>) at default.c:2411:15 [artificial]
    frame #17: 0x00000001000d7214 ruby`newobj_of [inlined] rb_gc_impl_new_obj(objspace_ptr=<unavailable>, cache_ptr=<unavailable>, klass=<unavailable>, flags=<unavailable>, wb_protected=<unavailable>, alloc_size=<unavailable>) at default.c:2490:15
    frame #18: 0x00000001000d719c ruby`newobj_of(cr=<unavailable>, klass=4313971728, flags=258, wb_protected=<unavailable>, size=<unavailable>) at gc.c:995:17
    frame #19: 0x00000001000d73ec ruby`rb_wb_protected_newobj_of(ec=<unavailable>, klass=<unavailable>, flags=<unavailable>, size=<unavailable>) at gc.c:1044:12 [artificial]
    frame #20: 0x0000000100032d34 ruby`class_alloc0(type=<unavailable>, klass=4313971728, namespaceable=<unavailable>) at class.c:803:5
```

We don't decrement the super and module subclasses count for iclasses that
are having their classext replaced. This causes the reference count to be
incorrect and leak memory.

The following script demonstrates the memory leak:

    module Foo
      refine(Object) do
        define_method(:<=) {}
      end
    end

    class Bar
      include Comparable
    end

With RUBY_FREE_AT_EXIT and ASAN, we can see many memory leaks, including:

    Direct leak of 16 byte(s) in 1 object(s) allocated from:
        #0 0x599f715adca2 in calloc (miniruby+0x64ca2)
        #1 0x599f716bd779 in calloc1 gc/default/default.c:1495:12
        ruby#2 0x599f716d1370 in rb_gc_impl_calloc gc/default/default.c:8216:5
        ruby#3 0x599f716b8ab1 in ruby_xcalloc_body gc.c:5221:12
        ruby#4 0x599f716b269c in ruby_xcalloc gc.c:5215:34
        ruby#5 0x599f715eab23 in class_alloc0 class.c:790:22
        ruby#6 0x599f715e4bec in class_alloc class.c:836:12
        ruby#7 0x599f715e60c9 in module_new class.c:1693:17
        ruby#8 0x599f715e60a2 in rb_module_new class.c:1701:12
        ruby#9 0x599f715e6303 in rb_define_module class.c:1733:14
        ruby#10 0x599f715ebc5f in Init_Comparable compar.c:315:22
        ruby#11 0x599f716e35f5 in rb_call_inits inits.c:32:5
        ruby#12 0x599f7169cbfd in ruby_setup eval.c:88:9
        ruby#13 0x599f7169cdac in ruby_init eval.c:100:17
        ruby#14 0x599f715b0fa9 in rb_main main.c:41:5
        ruby#15 0x599f715b0f59 in main main.c:62:12
        ruby#16 0x739b2f02a1c9 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
        ruby#17 0x739b2f02a28a in __libc_start_main csu/../csu/libc-start.c:360:3
        ruby#18 0x599f7157c424 in _start (miniruby+0x33424)

We don't decrement the super and module subclasses count for iclasses that
are having their classext replaced. This causes the reference count to be
incorrect and leak memory.

The following script demonstrates the memory leak:

    module Foo
      refine(Object) do
        define_method(:<=) {}
      end
    end

    class Bar
      include Comparable
    end

With RUBY_FREE_AT_EXIT and ASAN, we can see many memory leaks, including:

    Direct leak of 16 byte(s) in 1 object(s) allocated from:
        #0 0x599f715adca2 in calloc (miniruby+0x64ca2)
        #1 0x599f716bd779 in calloc1 gc/default/default.c:1495:12
        ruby#2 0x599f716d1370 in rb_gc_impl_calloc gc/default/default.c:8216:5
        ruby#3 0x599f716b8ab1 in ruby_xcalloc_body gc.c:5221:12
        ruby#4 0x599f716b269c in ruby_xcalloc gc.c:5215:34
        ruby#5 0x599f715eab23 in class_alloc0 class.c:790:22
        ruby#6 0x599f715e4bec in class_alloc class.c:836:12
        ruby#7 0x599f715e60c9 in module_new class.c:1693:17
        ruby#8 0x599f715e60a2 in rb_module_new class.c:1701:12
        ruby#9 0x599f715e6303 in rb_define_module class.c:1733:14
        ruby#10 0x599f715ebc5f in Init_Comparable compar.c:315:22
        ruby#11 0x599f716e35f5 in rb_call_inits inits.c:32:5
        ruby#12 0x599f7169cbfd in ruby_setup eval.c:88:9
        ruby#13 0x599f7169cdac in ruby_init eval.c:100:17
        ruby#14 0x599f715b0fa9 in rb_main main.c:41:5
        ruby#15 0x599f715b0f59 in main main.c:62:12
        ruby#16 0x739b2f02a1c9 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
        ruby#17 0x739b2f02a28a in __libc_start_main csu/../csu/libc-start.c:360:3
        ruby#18 0x599f7157c424 in _start (miniruby+0x33424)

We don't decrement the super and module subclasses count for iclasses that
are having their classext replaced. This causes the reference count to be
incorrect and leak memory.

The following script demonstrates the memory leak:

    module Foo
      refine(Object) do
        define_method(:<=) {}
      end
    end

    class Bar
      include Comparable
    end

With RUBY_FREE_AT_EXIT and ASAN, we can see many memory leaks, including:

    Direct leak of 16 byte(s) in 1 object(s) allocated from:
        #0 0x599f715adca2 in calloc (miniruby+0x64ca2)
        #1 0x599f716bd779 in calloc1 gc/default/default.c:1495:12
        #2 0x599f716d1370 in rb_gc_impl_calloc gc/default/default.c:8216:5
        #3 0x599f716b8ab1 in ruby_xcalloc_body gc.c:5221:12
        #4 0x599f716b269c in ruby_xcalloc gc.c:5215:34
        #5 0x599f715eab23 in class_alloc0 class.c:790:22
        #6 0x599f715e4bec in class_alloc class.c:836:12
        #7 0x599f715e60c9 in module_new class.c:1693:17
        #8 0x599f715e60a2 in rb_module_new class.c:1701:12
        #9 0x599f715e6303 in rb_define_module class.c:1733:14
        #10 0x599f715ebc5f in Init_Comparable compar.c:315:22
        #11 0x599f716e35f5 in rb_call_inits inits.c:32:5
        #12 0x599f7169cbfd in ruby_setup eval.c:88:9
        #13 0x599f7169cdac in ruby_init eval.c:100:17
        #14 0x599f715b0fa9 in rb_main main.c:41:5
        #15 0x599f715b0f59 in main main.c:62:12
        #16 0x739b2f02a1c9 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
        #17 0x739b2f02a28a in __libc_start_main csu/../csu/libc-start.c:360:3
        #18 0x599f7157c424 in _start (miniruby+0x33424)

These tests use NM threads but NT is not freed for MN thread, causing it
to be reported as memory leaks in LSAN. For example:

    #1 0x62ee7bc67e99 in calloc1 gc/default/default.c:1495:12
    ruby#2 0x62ee7bc7ba00 in rb_gc_impl_calloc gc/default/default.c:8216:5
    ruby#3 0x62ee7bc631d1 in ruby_xcalloc_body gc.c:5221:12
    ruby#4 0x62ee7bc5cdbc in ruby_xcalloc gc.c:5215:34
    ruby#5 0x62ee7bdea4c6 in native_thread_alloc thread_pthread.c:2187:35
    ruby#6 0x62ee7bdec31b in native_thread_check_and_create_shared thread_pthread_mn.c:429:39
    ruby#7 0x62ee7bdea484 in native_thread_create_shared thread_pthread_mn.c:531:12
    ruby#8 0x62ee7bdea1da in native_thread_create thread_pthread.c:2403:16
    ruby#9 0x62ee7bdde2eb in thread_create_core thread.c:884:11
    ruby#10 0x62ee7bde4466 in thread_initialize thread.c:992:16

These tests use NM threads but NT is not freed for MN thread, causing it
to be reported as memory leaks in LSAN. For example:

    #1 0x62ee7bc67e99 in calloc1 gc/default/default.c:1495:12
    ruby#2 0x62ee7bc7ba00 in rb_gc_impl_calloc gc/default/default.c:8216:5
    ruby#3 0x62ee7bc631d1 in ruby_xcalloc_body gc.c:5221:12
    ruby#4 0x62ee7bc5cdbc in ruby_xcalloc gc.c:5215:34
    ruby#5 0x62ee7bdea4c6 in native_thread_alloc thread_pthread.c:2187:35
    ruby#6 0x62ee7bdec31b in native_thread_check_and_create_shared thread_pthread_mn.c:429:39
    ruby#7 0x62ee7bdea484 in native_thread_create_shared thread_pthread_mn.c:531:12
    ruby#8 0x62ee7bdea1da in native_thread_create thread_pthread.c:2403:16
    ruby#9 0x62ee7bdde2eb in thread_create_core thread.c:884:11
    ruby#10 0x62ee7bde4466 in thread_initialize thread.c:992:16

These tests use NM threads but NT is not freed for MN thread, causing it
to be reported as memory leaks in LSAN. For example:

    #1 0x62ee7bc67e99 in calloc1 gc/default/default.c:1495:12
    #2 0x62ee7bc7ba00 in rb_gc_impl_calloc gc/default/default.c:8216:5
    #3 0x62ee7bc631d1 in ruby_xcalloc_body gc.c:5221:12
    #4 0x62ee7bc5cdbc in ruby_xcalloc gc.c:5215:34
    #5 0x62ee7bdea4c6 in native_thread_alloc thread_pthread.c:2187:35
    #6 0x62ee7bdec31b in native_thread_check_and_create_shared thread_pthread_mn.c:429:39
    #7 0x62ee7bdea484 in native_thread_create_shared thread_pthread_mn.c:531:12
    #8 0x62ee7bdea1da in native_thread_create thread_pthread.c:2403:16
    #9 0x62ee7bdde2eb in thread_create_core thread.c:884:11
    #10 0x62ee7bde4466 in thread_initialize thread.c:992:16

We need the VM barrier in rb_gc_impl_before_fork to stop the other Ractors
because otherwise they could be allocating objects in the fast path which
could be calling mmtk_add_obj_free_candidate. Since mmtk_add_obj_free_candidate
acquires a lock on obj_free_candidates in weak_proc.rs, this lock may not
be released in the child process after the Ractor dies.

For example, the following script demonstrates the issue:

    puts "Hello #{Process.pid}"

    100.times do |i|
      puts "i = #{i}"
      Ractor.new(i) do |j|
        puts "Ractor #{j} hello"
        1000.times do |i|
          s = "#{j}-#{i}"
        end
        Ractor.receive
        puts "Ractor #{j} goodbye"
      end
      pid = fork { }
      puts "Child pid is #{pid}"
      _, status = Process.waitpid2 pid
      puts status.success?
    end

    puts "Goodbye"

In the child process, we can see that it is stuck trying to acquire the
lock on obj_free_candidates:

    #5  0x00007192bfb53f10 in mmtk_ruby::weak_proc::WeakProcessor::get_all_obj_free_candidates (self=0x7192c0657498 <mmtk_ruby::BINDING+72>) at src/weak_proc.rs:52
    #6  0x00007192bfa634c3 in mmtk_ruby::api::mmtk_get_all_obj_free_candidates () at src/api.rs:295
    #7  0x00007192bfa61d50 in rb_gc_impl_shutdown_call_finalizer (objspace_ptr=0x578c17abfc50) at gc/mmtk/mmtk.c:1032
    #8  0x0000578c1601e48e in rb_ec_finalize (ec=0x578c17ac06d0) at eval.c:166
    #9  rb_ec_cleanup (ec=<optimized out>, ex=<optimized out>) at eval.c:257
    #10 0x0000578c1601ebf6 in ruby_cleanup (ex=<optimized out>) at eval.c:180
    #11 ruby_stop (ex=<optimized out>) at eval.c:292
    #12 0x0000578c16127124 in rb_f_fork (obj=<optimized out>) at process.c:4291
    #13 rb_f_fork (obj=<optimized out>) at process.c:4281

ruby/mmtk@eb4b229858

In rb_gc_impl_before_fork, it locks the VM and barriers all the Ractors
before calling mmtk_before_fork. However, since rb_mmtk_block_for_gc is
a barrier point, one or more Ractors could be paused there. However,
mmtk_before_fork is not compatible with that because it assumes that the
MMTk workers are idle, but the workers are not idle because they are
busy working on a GC.

This commit essentially implements a trylock. It will optimistically
lock but will release the lock if it detects that any other Ractors are
waiting in rb_mmtk_block_for_gc.

For example, the following script demonstrates the issue:

    puts "Hello #{Process.pid}"

    100.times do |i|
      puts "i = #{i}"
      Ractor.new(i) do |j|
        puts "Ractor #{j} hello"
        1000.times do |i|
          s = "#{j}-#{i}"
        end
        Ractor.receive
        puts "Ractor #{j} goodbye"
      end
      pid = fork { }
      puts "Child pid is #{pid}"
      _, status = Process.waitpid2 pid
      puts status.success?
    end

    puts "Goodbye"

We can see the MMTk worker thread is waiting to start the GC:

    #4  0x00007ffff66538b1 in rb_mmtk_stop_the_world () at gc/mmtk/mmtk.c:101
    #5  0x00007ffff6d04caf in mmtk_ruby::collection::{impl#0}::stop_all_mutators<mmtk::scheduler::gc_work::{impl#14}::do_work::{closure_env#0}<mmtk::plan::immix::gc_work::ImmixGCWorkContext<mmtk_ruby::Ruby, 0>>> (_tls=..., mutator_visitor=...) at src/collection.rs:23

However, the mutator thread is stuck in mmtk_before_fork trying to stop
that worker thread:

    #4  0x00007ffff6c0b621 in std::sys::thread::unix::Thread::join () at library/std/src/sys/thread/unix.rs:134
    #5  0x00007ffff6658b6e in std::thread::JoinInner<()>::join<()> (self=...)
    #6  0x00007ffff6658d4c in std::thread::JoinHandle<()>::join<()> (self=...)
    #7  0x00007ffff665795e in mmtk_ruby::binding::RubyBinding::join_all_gc_threads (self=0x7ffff72462d0 <mmtk_ruby::BINDING+8>) at src/binding.rs:115
    #8  0x00007ffff66561a8 in mmtk_ruby::api::mmtk_before_fork () at src/api.rs:309
    #9  0x00007ffff66556ff in rb_gc_impl_before_fork (objspace_ptr=0x555555d17980) at gc/mmtk/mmtk.c:1054
    #10 0x00005555556bbc3e in rb_gc_before_fork () at gc.c:5429

ruby/mmtk@1a629504a7