Can modify array during iteration

Ruby Development
#1

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1.9
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a = [0, 1, 2]
a.each do
a.each {}
a.clear
end
p a #=> []

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$ ./ruby -e ’
a = (0 … 100000).to_a
a.map! do |i|
if i == 99999
a.each { }
a.clear
end
i
end
’
-e:3: [BUG] Segmentation fault
ruby 1.9.0 (2008-01-23 revision 0) [i686-linux]

– control frame ----------
c:0004 p:---- s:0010 b:0010 l:000009 d:000009 CFUNC :map!
c:0003 p:0018 s:0007 b:0007 l:000006 d:000006 TOP -e:3
c:0002 p:---- s:0004 b:0004 l:000003 d:000003 FINISH :inherited
c:0001 p:0000 s:0002 b:0002 l:000001 d:000001 TOP :17

DBG> : “-e:3:in `’”
– backtrace of native function call (Use addr2line) –
0x80f04a5
0x810f3ce
0x810f42b
0x80bf860
0xffffe440
0x80598b1
0x80fabf5
0x80eecc3
0x80ea5ee
0x80edeb4
0x80ee1ed
0x805a6f9
0x805e840
0x8058121
0xb7dc1ea8
0x8058031

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Index: array.c

— array.c (revision 15191)
+++ array.c (working copy)
@@ -1644,7 +1644,7 @@

 rb_ary_modify(ary);
 for (i = 0; i < RARRAY_LEN(ary); i++) {
  • RARRAY_PTR(ary)[i] = rb_yield(RARRAY_PTR(ary)[i]);
  • rb_ary_store(ary, i, rb_yield(RARRAY_PTR(ary)[i]));
    }
    return ary;
    }
#2

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At Thu, 24 Jan 2008 00:03:24 +0900,
Yusuke ENDOH wrote in [ruby-dev:33328]:

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#3

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In message “Re: [ruby-dev:33343] Re: can modify array during iteration”
on Thu, 24 Jan 2008 13:05:43 +0900, Nobuyoshi N.
[email protected] writes:

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