# \[Bug:1.9\] duplicated when clause

**URL:** <https://www.ruby-forum.com/t/bug-1-9-duplicated-when-clause/149694>\
**Category:** Development\
**Created:** [September 28, 2008, 1:44pm UTC](https://www.ruby-forum.com/t/bug-1-9-duplicated-when-clause/149694 "2008-09-28T13:44:06Z")\
**Posts on this page:** 3\
**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 28, 2008, 1:44pm UTC](https://www.ruby-forum.com/t/bug-1-9-duplicated-when-clause/149694/1 "2008-09-28T13:44:06Z")

</div>

e$B1sF#$G$9!#e(B

when e$B@a$KF1$8CM$,$"$k$H$-$N5sF0$,e(B 1.8 e$B$He(B 1.9  
e$B$G0[$J$k$h$&$G$9!#e(B

$ ruby18 -e ’  
case 1  
when 1 then p :foo  
when 1 then p :bar  
end  
’  
:foo

$ ruby19 -e ’  
case 1  
when 1 then p :foo  
when 1 then p :bar  
end  
’  
:bar

1.9 e$B$N%P%0$G$O$J$$$+$H;W$$$^$9!#e(B  
e$B0J2\<$N%Q%C%A$r%3%\_%C%H$7$F$b$$$$$G$7$g$&$+!#e(B

# Index: compile.c

— compile.c (revision 19604)  
+++ compile.c (working copy)  
@@ -1349,7 +1349,9 @@  
rb\_compile\_error(RSTRING\_PTR(iseq-\>filename),  
iobj-\>line\_no,  
“unknown label”);  
}

- 

```
   rb_hash_aset(map, obj, INT2FIX(lobj->position - (pos+len)));

```

- 

```
   if (!st_lookup(rb_hash_tbl(map), obj, 0)) {

```

- 

```
       rb_hash_aset(map, obj, INT2FIX(lobj->position - 

```

(pos+len)));

- 

```
   }
     }
     generated_iseq[pos + 1 + j] = map;
     iseq_add_mark_object(iseq, map);
```

---

<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 28, 2008, 1:53pm UTC](https://www.ruby-forum.com/t/bug-1-9-duplicated-when-clause/149694/2 "2008-09-28T13:53:27Z")

</div>

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

Yusuke ENDOH wrote:

> 1.9 e$B$N%P%0$G$O$J$$$+$H;W$$$^$9!#e(B  
> e$B0J2\<$N%Q%C%A$r%3%\_%C%H$7$F$b$$$$$G$7$g$&$+!#e(B

e$B!!$O$$!%$\*4j$$$7$^$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:** [September 28, 2008, 3:17pm UTC](https://www.ruby-forum.com/t/bug-1-9-duplicated-when-clause/149694/3 "2008-09-28T15:17:53Z")

</div>

e$B%A%1%C%He(B #608 e$B$,99?7$5$l$^$7$?!#e(B (by Yusuke E.)

e$B%9%F!\<%?%9e(B Opene$B$+$ie(BClosede$B$KJQ99e(B  
e$B?JD=e(B % 0e$B$+$ie(B100e$B$KJQ99e(B

## Applied in changeset r19612.

[http://redmine.ruby-lang.org/issues/show/608](http://redmine.ruby-lang.org/issues/show/608)