[ID 20000731.010] regex error

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From: Doug Harrison <dsh@mvps.org>
Newsgroups: comp.lang.perl.misc
Subject: Possible regex regression in 5.6.0
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Date: Mon, 31 Jul 2000 22:35:48 GMT
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Consider the following program:

{
   $x = "1\nabcabcabcabc\n";
   print "match 1\n" if $x =~ /^.{9}abc.*\n/m;
}

{
   $x = "12\nabcabcabcabc\n";
   print "match 2\n" if $x =~ /^.{9}abc.*\n/m;
}

{
   # Fails in Perl 5.6.0
   $x = "123\nabcabcabcabc\n";
   print "match 3\n" if $x =~ /^.{9}abc.*\n/m;
}

{
   # Replacing penultimate 'c' with 'X' fixes it
   $x = "123\nabcabcabXabc\n";
   print "match 4\n" if $x =~ /^.{9}abc.*\n/m;
}

{
   # Replacing .* with .? fixes it
   $x = "123\nabcabcabcabc\n";
   print "match 5\n" if $x =~ /^.{9}abc.?\n/m;
}

Under 5.005_03, the output is:

match 1
match 2
match 3
match 4
match 5

Under 5.6.0 (ActivePerl build 616), the output is:

match 1
match 2
match 4
match 5

I don't see why 5.6.0 failed on match 3. Any ideas?

• [ID 20000731.010] regex error by mjd
• [PATCH bleadperl] [ID 20000731.010] regex error by Hugo
• Re: [PATCH bleadperl] [ID 20000731.010] regex error by Jarkko Hietaniemi