# Loop{x+=1&&next} dumps core

**URL:** <https://www.ruby-forum.com/t/loop-x-1-next-dumps-core/108434>\
**Category:** Development\
**Created:** [July 3, 2007, 1:53pm UTC](https://www.ruby-forum.com/t/loop-x-1-next-dumps-core/108434 "2007-07-03T13:53:05Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [July 3, 2007, 1:53pm UTC](https://www.ruby-forum.com/t/loop-x-1-next-dumps-core/108434/1 "2007-07-03T13:53:05Z")

</div>

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1.9 e$B$G0J2\<$N$h$&$K$9$k$HMn$A$^$9!#e(B

## $ ./ruby -e ‘loop{x+=1&&next}’ -e:1: – control frame ---------- c:0006 p:0011 s:0013 b:0012 l:000004 d:000011 BLOCK -e:1 c:0005 p:---- s:0010 b:0010 l:000009 d:000009 FINISH c:0004 p:---- s:0008 b:0008 l:000007 d:000007 CFUNC :loop c:0003 p:0007 s:0005 b:0005 l:000004 d:000004 TOP -e:1 c:0002 p:---- s:0003 b:0003 l:000002 d:000002 FINISH :inherited c:0001 p:---- s:0001 b:-001 l:000000 d:000000 ------

## DBG\> : “-e:1:in `loop'" DBG> : "-e:1:in`'” – backtrace of native function call (Use addr2line) – 0x80dad25 0x80f3f90 0x80d83f4 0x80d8814 0x80d8ec7 0x8059549 0x80d96c9 0x80d5364 0x80d8814 0x80d8b48 0x8059112 0x8059136 0x805d691 0x8056d8f 0xb7de6ea8 0x8056cc1

[BUG] Stack consistency error (sp: 13, bp: 12)  
ruby 1.9.0 (2007-07-03) [i686-linux]

e$B%"%!\<%H$7$^$7$?e(B (core dumped)

e$B$"$H!"e(Bloop{x+=1&&redo} e$B$G$bMn$A$^$9!#e(B

---

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [July 3, 2007, 5:21pm UTC](https://www.ruby-forum.com/t/loop-x-1-next-dumps-core/108434/2 "2007-07-03T17:21:49Z")

</div>

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Yusuke ENDOH wrote:

> 1.9 e$B$G0J2\<$N$h$&$K$9$k$HMn$A$^$9!#e(B  
> …  
> $ ./ruby -e ‘loop{x+=1&&next}’  
> …  
> e$B$"$H!"e(Bloop{x+=1&&redo} e$B$G$bMn$A$^$9!#e(B

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e$B!!$J$s$H$$$&$+!"Nc$($Pe(B 1 + (f?next:0)  
e$B$J$s$+$O%(%i!\<$J$N$G!“e(B1+  
(1&&next) e$B$b%(%i!\<$H$J$C$F$/$l$k$HNI$$$H;W$&$s$G$9$,!”%@%a$Ge(B  
e$B$7$g$&$+!#e(B

# Index: parse.y

— parse.y (e$B%j%S%8%g%se(B 12679)  
+++ parse.y (e$B:n6H%3%T!\<e(B)  
@@ -7452,8 +7452,6 @@ node\_assign\_gen(struct parser\_params \*pa  
static int  
value\_expr\_gen(struct parser\_params \*parser, NODE \*node)  
{

- int cond = 0;
- while (node) {  
switch (nd\_type(node)) {  
case NODE\_DEFN:  
@@ -7466,7 +7464,7 @@ value\_expr\_gen(struct parser\_params \*par  
case NODE\_NEXT:  
case NODE\_REDO:  
case NODE\_RETRY:
- 

```
 if (!cond) yyerror("void value expression");

```

- 

```
 yyerror("void value expression");
 /* or "control never reach"? */
 return Qfalse;

```

@@ -7488,7 +7486,6 @@ value\_expr\_gen(struct parser\_params \*par

```
 case NODE_AND:
 case NODE_OR:

```

- 

```
 cond = 1;
 node = node->nd_2nd;
 break;

```

e$B!!$7$+$7!"1sF#$5$s$h$/$3$s$J$N8+$D$1$i$l$^$9$M!#$d$C$Q$j%3!\<%Ie(B  
e$B$r@:::$5$l$F$k$s$G$7$g$&$+!#e(B

---

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [July 3, 2007, 9:19pm UTC](https://www.ruby-forum.com/t/loop-x-1-next-dumps-core/108434/3 "2007-07-03T21:19:17Z")

</div>

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

In message “Re: [ruby-dev:31120] Re: loop{x+=1&&next} dumps core”  
on Wed, 4 Jul 2007 00:20:59 +0900, SASADA Koichi [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

|e$B!!$?$H$($P!"e(B1.times{1+(1&&next)} e$B$G$b5/$-$^$9!#$D$^$j!“2?$i$+e(B  
|e$B$NCM$,@Q$^$l$F$$$k\>uBV$G!“e(Bnexte$B!Je(Bjumpe$B!K$9$k$H!”$=$N%4%\_$,;D$C$Fe(B  
|e$B$7$^$&!”$H$$$&\>I\>u$G$9!#e(B  
|  
|e$B!!$3$l$O:$$j$^$7$?!#$&$^$$2r7hJ}K!$,;W$$$D$-$^$;$s!#e(B

e$B$&!\<$`!#e(B

|e$B!!$J$s$H$$$&$+!"Nc$($Pe(B 1 + (f?next:0) e$B$J$s$+$O%(%i!\<$J$N$G!“e(B1+  
|(1&&next) e$B$b%(%i!\<$H$J$C$F$/$l$k$HNI$$$H;W$&$s$G$9$,!”%@%a$Ge(B  
|e$B$7$g$&$+!#e(B

e$B$(!\<$H!"e(B

xxx or next

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e$B$$$&$N$O%”%j$@$H;W$$$^$9!#$I$&$d$C$F8!=P$7$h$&$+!#e(B

---

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [July 3, 2007, 9:52pm UTC](https://www.ruby-forum.com/t/loop-x-1-next-dumps-core/108434/4 "2007-07-03T21:52:21Z")

</div>

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

Yukihiro M. wrote:

> e$B$@$H%D%i$$$N$G$9$,!“e(Band e$B$J$I$,\<0$NCf$K4^$^$l$F$$$?$i%(%i!\<$He(B  
> e$B$$$&$N$O%”%j$@$H;W$$$^$9!#$I$&$d$C$F8!=P$7$h$&$+!#e(B

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e$BDs0F$7$F$\*$j$^$9!#@h$[$I$N%a!\<%k$K=q$$$?%Q%C%A$,!"$^$5$Ke(B  
value\_expr() e$B$G$N%A%’%C%/$r87$7$/$9$k$b$N$J$s$G$9$,!"$^$:$$$Ge(B  
e$B$7$g$&$+!#e(B

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