# SEGV by regexp and thread

**URL:** <https://www.ruby-forum.com/t/segv-by-regexp-and-thread/133670>\
**Category:** Development\
**Created:** [April 2, 2008, 1:39pm UTC](https://www.ruby-forum.com/t/segv-by-regexp-and-thread/133670 "2008-04-02T13:39:07Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [April 2, 2008, 1:39pm UTC](https://www.ruby-forum.com/t/segv-by-regexp-and-thread/133670/1 "2008-04-02T13:39:07Z")

</div>

e$B0J2\<$N$h$&$K$9$k$He(B SEGV e$B$7$^$9!#e(B

% cat z.rb  
def m(s)  
/\Azzzzzz(\S)(\S)(\S)(\S\*)\z/ =~ s  
[$1.class, $2.class, $3.class, $4.class]  
end  
s1 = “z” \* 10000  
s1.force\_encoding(“EUC-JP”)  
s2 = “a”  
Thread.new { loop { p m(s1) } }  
loop { m(s2) }  
% ./ruby z.rb  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
z.rb:2: [BUG] Segmentation fault  
ruby 1.9.0 (2008-04-01 revision 15885) [i686-linux]

## – control frame ---------- c:0007 p:0004 s:0012 b:0012 l:000011 d:000011 METHOD z.rb:2 c:0006 p:0011 s:0008 b:0007 l:000884 d:000006 BLOCK z.rb:8 c:0005 p:---- s:0008 b:0008 l:000007 d:000007 FINISH c:0004 p:---- s:0006 b:0006 l:000005 d:000005 CFUNC :loop c:0003 p:0007 s:0003 b:0003 l:000884 d:000002 BLOCK z.rb:8 c:0002 p:---- s:0004 b:0004 l:000003 d:000003 FINISH c:0001 p:---- s:0002 b:0002 l:000001 d:000001 TOP

## DBG\> : “z.rb:8:in `block (2 levels) in <main>'" DBG> : "z.rb:8:in`loop’” DBG\> : “z.rb:8:in `block in '” – backtrace of native function call (Use addr2line) – 0x811195e 0x8137c77 0x8137caf 0x80d5c99 0xb7f8a440 0x80c7fbc 0x80afdc4 0x80b2715 0x80b273d 0x810e408 0x810f543 0x810848e 0x8108532 0x805c6db 0x805c84b 0x805cbb5 0x805c888 0x8107852 0x810f36a 0x810eeb4 0x810b66f 0x810f543 0x810848e 0x81085ed 0x81127cb 0x8111d0e 0xb7f6e240 0xb7ea249e

zsh: abort (core dumped) ./ruby z.rb  
% gdb ruby core.10383  
GNU gdb 6.4.90-debian  
Copyright © 2006 Free Software Foundation, Inc.  
GDB is free software, covered by the GNU General Public License, and you  
are  
welcome to change it and/or distribute copies of it under certain  
conditions.  
Type “show copying” to see the conditions.  
There is absolutely no warranty for GDB. Type “show warranty” for  
details.  
This GDB was configured as “i486-linux-gnu”…Using host libthread\_db  
library “/lib/tls/i686/cmov/libthread\_db.so.1”.

warning: Can’t read pathname for load map: Input/output error.  
Reading symbols from /lib/tls/i686/cmov/libpthread.so.0…done.  
Loaded symbols for /lib/tls/i686/cmov/libpthread.so.0  
Reading symbols from /lib/tls/i686/cmov/librt.so.1…done.  
Loaded symbols for /lib/tls/i686/cmov/librt.so.1  
Reading symbols from /lib/tls/i686/cmov/libdl.so.2…done.  
Loaded symbols for /lib/tls/i686/cmov/libdl.so.2  
Reading symbols from /lib/tls/i686/cmov/libcrypt.so.1…done.  
Loaded symbols for /lib/tls/i686/cmov/libcrypt.so.1  
Reading symbols from /lib/tls/i686/cmov/libm.so.6…done.  
Loaded symbols for /lib/tls/i686/cmov/libm.so.6  
Reading symbols from /lib/tls/i686/cmov/libc.so.6…done.  
Loaded symbols for /lib/tls/i686/cmov/libc.so.6  
Reading symbols from /lib/ld-linux.so.2…Reading symbols from  
/usr/lib/debug/lib/ld-2.3.6.so…done.  
done.  
Loaded symbols for /lib/ld-linux.so.2  
Reading symbols from  
/home/akr/ruby/yarvo0/lib/ruby/1.9.0/i686-linux/enc/euc\_jp.so…done.  
Loaded symbols for  
/home/akr/ruby/yarvo0/lib/ruby/1.9.0/i686-linux/enc/euc\_jp.so  
Reading symbols from /lib/libgcc\_s.so.1…done.  
Loaded symbols for /lib/libgcc\_s.so.1  
Core was generated by `./ruby z.rb’.  
Program terminated with signal 6, Aborted.  
#0 0xb7f8a410 in ?? ()  
(gdb) bt  
#0 0xb7f8a410 in ?? ()  
#1 0xb7c988ac in ?? ()  
#2 0x00000006 in ?? ()  
#3 0x00002891 in ?? ()  
#4 0xb7dff811 in raise () from /lib/tls/i686/cmov/libc.so.6  
#5 0xb7e00fb9 in abort () from /lib/tls/i686/cmov/libc.so.6  
#6 0x08137cb4 in rb\_bug (fmt=0x816d5c7 “Segmentation fault”) at  
error.c:226  
#7 0x080d5c99 in sigsegv (sig=11) at signal.c:546  
#8 0xb7f8a440 in ?? ()  
#9 0x0000000b in ?? ()  
#10 0xb7c98a3c in ?? ()  
#11 0xb7c98abc in ?? ()  
#12 0x0000000b in ?? ()  
#13 0x00000000 in ?? ()  
(gdb) run z.rb  
Starting program: /home/akr/ruby/yarvo0/ruby/ruby z.rb  
[Thread debugging using libthread\_db enabled]  
[New Thread -1209955456 (LWP 10398)]  
[New Thread -1210692688 (LWP 10401)]  
[New Thread -1211249744 (LWP 10402)]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]  
[String, String, String, String]

Program received signal SIGSEGV, Segmentation fault.  
[Switching to Thread -1211249744 (LWP 10402)]  
0x00000003 in ?? ()  
(gdb) bt  
#0 0x00000003 in ?? ()  
#1 0x080be257 in onigenc\_mbclen\_approximate (p=0x8207a50 ‘z’ \<repeats  
200 times\>…, e=0x820a160 “”, enc=0xb7d947a4)  
at regenc.c:56  
#2 0x080c7fbc in onig\_search (reg=0x823d588, str=0x8207a50 ‘z’ \<repeats  
200 times\>…, end=0x820a160 “”,  
start=0x8207a50 ‘z’ \<repeats 200 times\>…, range=0x8207a51 ‘z’  
\<repeats 200 times\>…, region=0x81a0f50, option=0)  
at regexec.c:3610  
#3 0x080afdc4 in rb\_reg\_search (re=3084291360, str=3084288840, pos=0,  
reverse=0) at re.c:1271  
#4 0x080b2715 in reg\_match\_pos (re=3084291360, strp=0xb7cdafa4, pos=0)  
at re.c:2475  
#5 0x080b273d in rb\_reg\_match (re=3084291360, str=3084288840) at  
re.c:2522  
#6 0x0810e408 in vm\_eval (th=0x8214448, initial=0) at insns.def:2020  
#7 0x0810f543 in vm\_eval\_body (th=0x8214448) at vm.c:1147  
#8 0x0810848e in invoke\_block (th=0x8214448, block=0xb7d5cf74,  
self=3084465740, argc=0, argv=0x0, blockptr=0x0) at vm.c:572  
#9 0x08108532 in vm\_yield (th=0x8214448, argc=0, argv=0x0) at vm.c:589  
#10 0x0805c6db in rb\_yield\_0 (argc=0, argv=0x0) at eval.c:910  
#11 0x0805c84b in loop\_i () at eval.c:970  
#12 0x0805cbb5 in rb\_rescue2 (b\_proc=0x805c831 \<loop\_i\>, data1=0,  
r\_proc=0, data2=0) at eval.c:1108  
#13 0x0805c888 in rb\_f\_loop () at eval.c:992  
#14 0x08107852 in call\_cfunc (func=0x805c84d \<rb\_f\_loop\>,  
recv=3084465740, len=0, argc=0, argv=0xb7cdd018)  
at vm\_insnhelper.c:285  
#15 0x0810f36a in vm\_call\_cfunc (th=0x8214448, reg\_cfp=0xb7d5cf60,  
num=0, id=4064, recv=3084465740, klass=3084473920,  
flag=8, mn=0xb7d8da94, blockptr=0xb7d5cf74) at vm\_insnhelper.c:372  
#16 0x0810eeb4 in vm\_call\_method (th=0x8214448, cfp=0xb7d5cf60, num=0,  
blockptr=0xb7d5cf74, flag=8, id=4064, mn=0xb7d8da6c,  
recv=3084465740, klass=3084465720) at vm\_insnhelper.c:504  
#17 0x0810b66f in vm\_eval (th=0x8214448, initial=0) at insns.def:1056  
#18 0x0810f543 in vm\_eval\_body (th=0x8214448) at vm.c:1147  
#19 0x0810848e in invoke\_block (th=0x8214448, block=0x8206c68,  
self=3084465740, argc=0, argv=0x8207008, blockptr=0x0)  
at vm.c:572  
#20 0x081085ed in vm\_invoke\_proc (th=0x8214448, proc=0x8206c68,  
self=3084465740, argc=0, argv=0x8207008, blockptr=0x0)  
at vm.c:606  
#21 0x081127cb in thread\_start\_func\_2 (th=0x8214448,  
stack\_start=0xb7cdc450) at thread.c:314  
#22 0x08111d0e in thread\_start\_func\_1 (th\_ptr=0x8214448) at  
thread\_pthread.c:175  
#23 0xb7fb0240 in start\_thread () from  
/lib/tls/i686/cmov/libpthread.so.0  
#24 0xb7ee449e in clone () from /lib/tls/i686/cmov/libc.so.6  
(gdb) up  
#1 0x080be257 in onigenc\_mbclen\_approximate (p=0x8207a50 ‘z’ \<repeats  
200 times\>…, e=0x820a160 “”, enc=0xb7d947a4)  
at regenc.c:56  
56 int ret = ONIGENC\_PRECISE\_MBC\_ENC\_LEN(enc,p,e);  
(gdb) p _enc  
$1 = {precise\_mbc\_enc\_len = 0x3, name = 0xb7d94790 “\003\b”, max\_enc\_len  
= 135983448, min\_enc\_len = 135983464,  
is\_mbc\_newline = 0, mbc\_to\_code = 0x410407, code\_to\_mbclen = 0,  
code\_to\_mbc = 0x436c694e, mbc\_case\_fold = 0x7373616c,  
apply\_all\_case\_fold = 0, get\_case\_fold\_codes\_by\_str = 0x11f,  
property\_name\_to\_ctype = 0, is\_code\_ctype = 0,  
get\_ctype\_code\_range = 0xb7d947e0, left\_adjust\_char\_head = 0,  
is\_allowed\_reverse\_match = 0x1f, auxiliary\_data = 0x0,  
ruby\_encoding\_index = -1210496316}  
(gdb) up  
 #2 0x080c7fbc in onig\_search (reg=0x823d588, str=0x8207a50 ‘z’ \<repeats  
200 times\>…, end=0x820a160 “”,  
start=0x8207a50 ‘z’ \<repeats 200 times\>…, range=0x8207a51 ‘z’  
\<repeats 200 times\>…, region=0x81a0f50, option=0)  
at regexec.c:3610  
3610 s += enclen(reg-\>enc, s, end);  
(gdb) up  
 #3 0x080afdc4 in rb\_reg\_search (re=3084291360, str=3084288840, pos=0,  
reverse=0) at re.c:1271  
1271 result = onig\_search(RREGEXP(re)-\>ptr,  
(gdb) l  
1266 rb\_reg\_prepare\_re(re, str, 1);  
1267  
1268 if (!reverse) {  
1269 range += RSTRING\_LEN(str);  
1270 }  
1271 result = onig\_search(RREGEXP(re)-\>ptr,  
1272 (UChar_)(RSTRING\_PTR(str)),  
1273 ((UChar\*)(RSTRING\_PTR(str)) +  
RSTRING\_LEN(str)),  
1274 ((UChar\*)(RSTRING\_PTR(str)) + pos),  
1275 ((UChar\*)range),  
(gdb) rp re  
T\_REGEXP: “\Azzzzzz(\S)(\S)(\S)(\S\*)\z” len:27 (literal)  
encoding:2 $2 = (struct RRegexp \*) 0xb7d68d20  
(gdb) p _$2  
$3 = {basic = {flags = 4259848, klass = 3084404360}, ptr = 0x81f8ab0,  
len = 27,  
str = 0x8203e98 "\Azzzzzz(\S)(\S)(\S)(\S_)\z"}  
(gdb) p \*$2-\>ptr  
$4 = {p = 0x8203da8 “#\a\006”, used = 180, alloc = 216, state = 0,  
num\_mem = 4, num\_repeat = 0, num\_null\_check = 0,  
num\_comb\_exp\_check = -1210497116, num\_call = 0, capture\_history = 0,  
bt\_mem\_start = 0, bt\_mem\_end = 0,  
stack\_pop\_level = 0, repeat\_range\_alloc = 0, repeat\_range = 0x0, enc =  
0x81ac940, options = 0, syntax = 0x8193320,  
case\_fold\_flag = 1073741824, name\_table = 0x0, optimize = 2,  
threshold\_len = 6, anchor = 9, anchor\_dmin = 9,  
anchor\_dmax = 4294967295, sub\_anchor = 0, exact = 0x81fb2a8 “zzzzzz”,  
exact\_end = 0x81fb2ae “”,  
map = ‘\006’ \<repeats 122 times\>, “\001”, ‘\006’ \<repeats 133 times\>,  
int\_map = 0x0, int\_map\_backward = 0x0, dmin = 0,  
dmax = 0, chain = 0x0}  
(gdb) p \*$2-\>ptr-\>enc  
$5 = {precise\_mbc\_enc\_len = 0x8151b84 \<us\_ascii\_mbc\_enc\_enc\_len\>, name =  
0x81ac930 “US-ASCII”, max\_enc\_len = 1,  
min\_enc\_len = 1, is\_mbc\_newline = 0x80beb97  
\<onigenc\_is\_mbc\_newline\_0x0a\>,  
mbc\_to\_code = 0x80bebfc \<onigenc\_single\_byte\_mbc\_to\_code\>,  
code\_to\_mbclen = 0x80bec0a \<onigenc\_single\_byte\_code\_to\_mbclen\>,  
code\_to\_mbc = 0x80bec14 \<onigenc\_single\_byte\_code\_to\_mbc\>,  
mbc\_case\_fold = 0x80bebc4 \<onigenc\_ascii\_mbc\_case\_fold\>,  
apply\_all\_case\_fold = 0x80be5f9 \<onigenc\_ascii\_apply\_all\_case\_fold\>,  
get\_case\_fold\_codes\_by\_str = 0x80be6b0  
\<onigenc\_ascii\_get\_case\_fold\_codes\_by\_str\>,  
property\_name\_to\_ctype = 0x80bef53  
\<onigenc\_minimum\_property\_name\_to\_ctype\>,  
is\_code\_ctype = 0x80bec44 \<onigenc\_ascii\_is\_code\_ctype\>,  
get\_ctype\_code\_range = 0x80beb8d  
\<onigenc\_not\_support\_get\_ctype\_code\_range\>,  
left\_adjust\_char\_head = 0x80bec28  
\<onigenc\_single\_byte\_left\_adjust\_char\_head\>,  
is\_allowed\_reverse\_match = 0x80bec30  
\<onigenc\_always\_true\_is\_allowed\_reverse\_match\>, auxiliary\_data =  
0xb7d92d3c,  
ruby\_encoding\_index = 2}  
(gdb)

---

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [April 12, 2008, 2:31pm UTC](https://www.ruby-forum.com/t/segv-by-regexp-and-thread/133670/2 "2008-04-12T14:31:14Z")

</div>

e$B$^$D$b$He(B e$B$f$-$R$m$G$9e(B

In message “Re: [ruby-dev:34223] SEGV by regexp and thread”  
on Wed, 2 Apr 2008 20:38:24 +0900, Tanaka A. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

|e$B0J2\<$N$h$&$K$9$k$He(B SEGV e$B$7$^$9!#e(B

onig\_search()e$B$NESCf$Ge(BRUBY\_VM\_CHECK\_INTS()e$B$,8F$P$l!"$=$3$G%3e(B  
e$B%s%F%-%9%H%9%$%C%A$,8F$P$l$k$?$a!“F1$8@55,I=8=%\*%V%8%'%/%H$Ke(B  
e$BBP$7$Fe(Brb\_reg\_prepare\_re()e$B$,8F$P$l$F;HMQCf$Ne(Bregex\_te$B$,e(Bfreee$B$5$le(B  
e$B$F$7$^$&$?$a!”$3$N$h$&$J8=\>]$,5/$-$k$h$&$G$9!#e(B

e$B%j%(%s%H%i%s%H$G$J$$4X?t$G$b3d$j9~$\_%A%'%C%/$r9T$$$?$$$3$H$,e(B  
e$B$"$k$?$a!"e(BRUBY\_VM\_CHECK\_INTS()e$B$G$O%3%s%F%-%9%H%9%$%C%A$r9T$Ce(B  
e$B$F$O$$$1$J$$$N$@$H;W$$$^$9!#e(B

e$B\<B:]!"e(Brb\_thread\_execute\_interrupts()e$B$+$ie(Brb\_thread\_schedule()  
e$B$r:o$k$H$3$NLdBj$OH/@8$7$^$;$s!#e(B

e$B$7$+$7!"$3$l$r:o$C$F$7$^$&$He(Bbootstraptest/test\_thread.rbe$B$,$&e(B  
e$B$^$/F0$+$J$/$J$C$F$7$^$&$s$G$9$h$M$(!#$I$&$d$C$FN\>N)$5$;$?$ie(B  
e$B$h$$$N$+J,$+$j$^$;$s!#e(B

---

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [April 14, 2008, 1:52am UTC](https://www.ruby-forum.com/t/segv-by-regexp-and-thread/133670/3 "2008-04-14T01:52:45Z")

</div>

e$B!!$5$5$@$G$9!%e(B

Yukihiro M. wrote:

> e$B$r:o$k$H$3$NLdBj$OH/@8$7$^$;$s!#e(B
> 
> e$B$7$+$7!"$3$l$r:o$C$F$7$^$&$He(Bbootstraptest/test\_thread.rbe$B$,$&e(B  
> e$B$^$/F0$+$J$/$J$C$F$7$^$&$s$G$9$h$M$(!#$I$&$d$C$FN\>N)$5$;$?$ie(B  
> e$B$h$$$N$+J,$+$j$^$;$s!#e(B

e$B!!%9%1%8%e!\<%j%s%02DG=$+$I$&$+$N%A%’%C%/$H3d$j9~$\_%A%’%C%/$rJL!9$K$7e(B  
e$B$^$9$+!)!!e(B1.8 e$B$@$HJL!9$G$7$?$C$1!)e(B

e$B!!$?$H$($=$&$7$F$b!$3d$j9~$\_%O%s%I%iCf$K6/@)E\*$KJL$N%9%l%C%I$K=hM}$re(B  
e$B0$7$?$iF1$8LdBj$,5/$-$=$&$G$9!%e(B

---

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [April 14, 2008, 4:08am UTC](https://www.ruby-forum.com/t/segv-by-regexp-and-thread/133670/4 "2008-04-14T04:08:53Z")

</div>

e$B$^$D$b$He(B e$B$f$-$R$m$G$9e(B

e$BIw\<Y0z$-$^$7$?!#e(B

In message “Re: [ruby-dev:34388] Re: SEGV by regexp and thread”  
on Mon, 14 Apr 2008 08:51:33 +0900, SASADA Koichi [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

|Yukihiro M. wrote:  
|\> onig\_search()e$B$NESCf$Ge(BRUBY\_VM\_CHECK\_INTS()e$B$,8F$P$l!"$=$3$G%3e(B  
|\> e$B%s%F%-%9%H%9%$%C%A$,8F$P$l$k$?$a!"F1$8@55,I=8=%\*%V%8%'%/%H$Ke(B  
|\> e$BBP$7$Fe(Brb\_reg\_prepare\_re()e$B$,8F$P$l$F;HMQCf$Ne(Bregex\_te$B$,e(Bfreee$B$5$le(B

|e$B!!%9%1%8%e!\<%j%s%02DG=$+$I$&$+$N%A%‘%C%/$H3d$j9~$\_%A%’%C%/$rJL!9$K$7e(B  
|e$B$^$9$+!)!!e(B1.8 e$B$@$HJL!9$G$7$?$C$1!)e(B

e$B$(!\<$H!"JL$K$J$C$F$O$$$J$+$C$?$H;W$$$^$9!#$H$$$&$3$H$O!"e(B1.8  
e$B$G$bF1$8LdBj$,5/$-$k$C$F$3$H$+$J!#e(B

|e$B!!$?$H$($=$&$7$F$b!$3d$j9~$\_%O%s%I%iCf$K6/@)E\*$KJL$N%9%l%C%I$K=hM}$re(B  
|e$B0$7$?$iF1$8LdBj$,5/$-$=$&$G$9!%e(B

e$B@oN,$O$$$/$D$+$"$C$Fe(B

- e$B%j%(%s%H%i%s%H$K$9$k!#e(B

- e$BNc30$d3d$j9~$\_$O5v2D!#%3%s%F%-%9%H%9%$%C%A$d%f!\<%6Dj5A%7%0e(B  
e$B%J%k%O%s%I%i$N\<B9T$OIT5v2De(B

- e$B$=$NB\>e(B

e$B$I$&$7$^$7$g$&$+$M!#e(B