# Meta programming might dump core

**URL:** <https://www.ruby-forum.com/t/meta-programming-might-dump-core/115387>\
**Category:** Development\
**Created:** [September 24, 2007, 7:50pm UTC](https://www.ruby-forum.com/t/meta-programming-might-dump-core/115387 "2007-09-24T19:50:03Z")\
**Posts on this page:** 2\
**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:** [September 24, 2007, 7:50pm UTC](https://www.ruby-forum.com/t/meta-programming-might-dump-core/115387/1 "2007-09-24T19:50:03Z")

</div>

e$B1sF#$H?=$7$^$9!#e(B

e$B$/$@$i$J$$Js9p$P$+$j$G62=L$G$9$,!"e(B[ruby-dev:31848]  
e$B$H;w$?$h$&$J%P%0$re(B  
e$BE,Ev$KC5$7$F$\_$^$7$?!#e(B1.9 e$B$P$C$+$j$G$9!#e(B

# e$B860x$rD4$Y$k5$NO$,L5$$$N$GJs9p$@$1$G$9$\_$^$;$s!#e(B

e$BLse(B 100 e$BK|%(%s%H%j$N%O%C%7%e%j%F%i%ke(B:

## $ time ./ruby -ve ‘eval("{" + “0=\>0,” \* 1000000 + “0=\>0}”)’ ruby 1.9.0 (2007-09-24 patchlevel 0) [i686-linux] (eval):1: – control frame ---------- c:0006 p:261958 s:302670847 b:0012 l:000004 d:000011 EVAL (eval):1 c:0005 p:---- s:0011 b:0011 l:000010 d:000010 FINISH :new c:0004 p:---- s:0009 b:0009 l:000008 d:000008 CFUNC :eval c:0003 p:0018 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 ------

SEGV recieved in SEGV handler

real 0m13.298s  
user 0m6.130s  
sys 0m6.510s

e$BLse(B 100 e$BK|JQ?t$NB?=EBeF~e(B:

## $ time ./ruby -ve ‘p eval(“x,” \* 1000000 + “=0”)’ ruby 1.9.0 (2007-09-24 patchlevel 0) [i686-linux] (eval):1: – control frame ---------- c:0006 p:0006 s:1000015 b:0014 l:000004 d:000013 EVAL (eval):1 c:0005 p:---- s:0012 b:0012 l:000011 d:000011 FINISH :new c:0004 p:---- s:0010 b:0010 l:000009 d:000009 CFUNC :eval c:0003 p:0016 s:0006 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 ------

SEGV recieved in SEGV handler

real 0m8.164s  
user 0m3.510s  
sys 0m4.580s

e$BLse(B 100 e$BK|0z?t$N%a%=%C%I8F$S=P$7e(B:

## $ time ./ruby -ve ‘def foo(\*a); end; eval(“foo(” + “0,” \* 1000000 + “0)”)’ ruby 1.9.0 (2007-09-24 patchlevel 0) [i686-linux] (eval):1: – control frame ---------- c:0006 p:261957 s:302705663 b:0012 l:000004 d:000011 EVAL (eval):1 c:0005 p:---- s:0011 b:0011 l:000010 d:000010 FINISH :new c:0004 p:---- s:0009 b:0009 l:000008 d:000008 CFUNC :eval c:0003 p:0018 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 ------

SEGV recieved in SEGV handler

real 0m6.178s  
user 0m2.910s  
sys 0m3.200s

false e$B$,e(B || e$B$Ge(B 25000 e$B8DO"$J$C$?\<0e(B:

$ time ./ruby -ve ‘eval(“false||” \* 25000 + “true”)’  
ruby 1.9.0 (2007-09-24 patchlevel 0) [i686-linux]  
e$B%;%0%a%s%F!\<%7%g%s0cH?$G$9e(B

real 0m3.888s  
user 0m3.390s  
sys 0m0.490s

---

<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:** [September 25, 2007, 10:06pm UTC](https://www.ruby-forum.com/t/meta-programming-might-dump-core/115387/2 "2007-09-25T22:06:38Z")

</div>

e$B$J$+$@$G$9!#e(B

At Tue, 25 Sep 2007 02:49:24 +0900,  
Yusuke ENDOH wrote in [ruby-dev:31850]:

> e$BLse(B 100 e$BK|%(%s%H%j$N%O%C%7%e%j%F%i%ke(B:

key=\>valuee$B$NCM$r@h$Ke(BVMe$B%9%?%C%/$K$9$Y$F@Q$s$G$+$ie(Bnewhashe$B$r\<B9T$9e(B  
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e$B$&$N$O!"B.EYE_$JLdBj$+$i$5$5$@$5$s$,5$$KF~$i$J$$$h$&$G!#e(B

e$B;W$$IU$/$N$O$3$N$"$?$j!#e(B  
(a) e$BB.EY$O\>/!9$"$-$i$a$F!"0lAH$:$DDI2Ce(B  
(b) VMe$B%9%?%C%/$r3NJ]$G$-$k$+3NG’$9$kL?Na$rDI2Ce(B

> e$BLse(B 100 e$BK|JQ?t$NB?=EBeF~e(B:

e$B$3$l$be(Bexpandarraye$B$Ge(B100e$BK|8D$KE83+$9$k$H$-$K%\*!\<%P!\<%U%m!\<$7$F$$$^e(B  
e$B$9!#e(Bexpandarraye$B$O%5%$%:$,$o$+$C$F$$$k$N$G!"%A%’%C%/$rF~$l$l$P$$e(B  
e$B$$$N$G$O$J$$$+$H!#e(B

> e$BLse(B 100 e$BK|0z?t$N%a%=%C%I8F$S=P$7e(B:

e$B$3$l$b0z?t$r0lEY%9%?%C%/$KA4It@Q$`$N$G0J2\<F1J8!#e(B

> false e$B$,e(B || e$B$Ge(B 25000 e$B8DO"$J$C$?\<0e(B:
> 
> $ time ./ruby -ve ‘eval(“false||” \* 25000 + “true”)’  
> ruby 1.9.0 (2007-09-24 patchlevel 0) [i686-linux]  
> e$B%;%0%a%s%F!\<%7%g%s0cH?$G$9e(B

e$B$3$C$A$Oe(Bbytecodee$B$K%3%s%Q%$%k$9$k$H$3$m$G%^%7%s%9%?%C%/%\*!\<%P!\<%Ue(B  
e$B%m!\<$7$F$$$^$9!#e(B

e$B$3$NNc$K$D$$$F$O2sHr$9$k$N$O4JC1$G$9$,!"$b$C$HJ#;($K%M%9%H$7$F$$e(B  
e$B$?$j$9$k$H$\*e$2$G$7$g$&!#e(B

# Index: compile.c

— compile.c (revision 13509)  
+++ compile.c (working copy)  
@@ -1795,9 +1795,14 @@ compile\_branch\_condition(rb\_iseq\_t \*iseq  
LABEL \*then\_label, LABEL \*else\_label)  
{

- again:  
switch (nd\_type(cond)) {  
case NODE\_NOT:

- compile\_branch\_condition(iseq, ret, cond-\>nd\_body, else\_label,
- 

```
    then_label);

```

- break;

- {

- 

```
 LABEL *tmp = else_label;

```

- 

```
 else_label = then_label;

```

- 

```
 then_label = tmp;

```

- 

```
 cond = cond->nd_body;

```

- 

```
 goto again;

```

- }

@@ -1807,7 +1812,6 @@ compile\_branch\_condition(rb\_iseq\_t \*iseq  
else\_label);  
ADD\_LABEL(ret, label);

- 

```
 compile_branch_condition(iseq, ret, cond->nd_2nd, then_label,

```

- 

```
        else_label);

```

- 

```
 break;

```

- 

```
 cond = cond->nd_2nd;

```

- 

```
 goto again;

```

}  
case NODE\_OR:  
@@ -1817,7 +1821,6 @@ compile\_branch\_condition(rb\_iseq\_t \*iseq  
label);  
ADD\_LABEL(ret, label);

- 

```
 compile_branch_condition(iseq, ret, cond->nd_2nd, then_label,

```

- 

```
        else_label);

```

- 

```
 break;

```

- 

```
 cond = cond->nd_2nd;

```

- 

```
 goto again;

```

}  
case NODE\_LIT: /\* NODE\_LIT is always not true \*/  
@@ -3187,18 +3190,20 @@ iseq\_compile\_each(rb\_iseq\_t \*iseq, LINK\_  
case NODE\_OR:{  
LABEL \*end\_label = NEW\_LABEL(nd\_line(node));

- COMPILE(ret, “nd\_1st”, node-\>nd\_1st);
- if (!poped) {
- 

```
 ADD_INSN(ret, nd_line(node), dup);

```

- }
- if (type == NODE\_AND) {
- 

```
 ADD_INSNL(ret, nd_line(node), branchunless, end_label);

```

- }
- else {
- 

```
 ADD_INSNL(ret, nd_line(node), branchif, end_label);

```

- }
- if (!poped) {
- 

```
 ADD_INSN(ret, nd_line(node), pop);

```

- }
- COMPILE\_(ret, “nd\_2nd”, node-\>nd\_2nd, poped);

- do {
- 

```
 COMPILE(ret, "nd_1st", node->nd_1st);

```

- 

```
 if (!poped) {

```

- ADD\_INSN(ret, nd\_line(node), dup);
- 

```
 }

```

- 

```
 if (type == NODE_AND) {

```

- ADD\_INSNL(ret, nd\_line(node), branchunless, end\_label);
- 

```
 }

```

- 

```
 else {

```

- ADD\_INSNL(ret, nd\_line(node), branchif, end\_label);
- 

```
 }

```

- 

```
 if (!poped) {

```

- ADD\_INSN(ret, nd\_line(node), pop);
- 

```
 }

```

- } while ((node = node-\>nd\_2nd) != 0 && nd\_type(node) == type);
- COMPILE\_(ret, “nd\_2nd”, node, poped);  
ADD\_LABEL(ret, end\_label);  
break;