From: Pavel Smerk <smerk@...>
Date: 2006-08-03T02:35:14+09:00
Subject: irb: Segmentation fault

	Hello folks,

in the following two cases irb fails (I've removed spaces from the 
=~/^irb/ lines to prevent line breaks):

$ irb
irb(main):001:0>"ahoj".split(//).join('|')
=> "a|h|o|j"
irb(main):002:0>"ahoj".split(/(?<=(?![Cc][Hh]).)/).join('|')
SyntaxError: compile error
(irb):2: undefined (?...) sequence: /(?<=(?![Cc][Hh]).)/
         from (irb):2
irb(main):003:0>"ahoj".split(/(?!ch)/).join('|')
=> "a|h|o|j"
irb(main):004:0>"achoj".split(/(?!ch)/).join('|')
=> "ac|h|o|j"
irb(main):005:0>"achoj".gsub(/([Cc])([Hh])/,'$1_$2').split(/(?!_[Hh])/).join('|')
=> "a|$|1|_|$|2|o|j"
irb(main):006:0>"achoj".gsub(/([Cc])([Hh])/,'\1_\2').split(/(?!_[Hh])/).join('|')
/usr/lib/ruby/1.8/irb/ruby-lex.rb:979: [BUG] Segmentation fault
ruby 1.8.2 (2005-04-11) [i386-linux]

Ne�sp��n� ukon�en (SIGABRT)
$

$ irb
irb(main):001:0>"ahoj".split(//).join('|')
=> "a|h|o|j"
irb(main):002:0>"ahoj".split(/(?<=(?![Cc][Hh]).)/).join('|')
SyntaxError: compile error
(irb):2: undefined (?...) sequence: /(?<=(?![Cc][Hh]).)/
         from (irb):2
irb(main):003:0>"ahoj".split(/(?!ch)/).join('|')
=> "a|h|o|j"
irb(main):004:0>"achoj".gsub(/([Cc])([Hh])/,'$1_$2').split(/(?!_[Hh])/).join('|')
=> "a|$|1|_|$|2|o|j"
irb(main):005:0>"achoj".gsub(/([Cc])([Hh])/,'\1_\2').split(/(?!_[Hh])/).join('|')
=> "a|c_|h|o|j"
/usr/lib/ruby/1.8/irb.rb:265: [BUG] Segmentation fault
ruby 1.8.2 (2005-04-11) [i386-linux]

Ne�sp��n� ukon�en (SIGABRT)
$

["Ne�sp��n� ukon�en" is perhaps some Czech translation of SIGABRT]

If I repeat it exactly as shown, irb fails. I've tried to skip some 
statements, but only the fourth could be skipped to get Segmentation 
fault --- and even in this case the error message differed (and return 
value was got compared to the first case). Skipping whichever else does 
not lead to failure. I haven't tried simplifying of the statements too 
much (only a bit, but unsuccessfully with respect to retain the irb 
failure).

Please, could someone test it with current version of ruby/irb?

Where should one post such bugreports?

Regards,

P.