I seem to have stumbled across a bug in Perl 5.8.4, and I'm wondering if anyone else can help me confirm it's a bug.

Basically I have a piece of software here containing a module Browser.pm. It's been running fine for me on FreeBSD with perl 5.8.5 (and also on some earlier versions of perl), and I have users running it ok on Mandrake and Windows. However, I find that on perl 5.8.4 on Debian-Sarge, if I do "perl -c Browser.pm", perl goes into an endless loop, eating CPU like crazy. I'd appreciate it greatly if anyone could supply more data points, by downloading the tarball and running a perl -c on it on their own system. At this point I'm not sure if (a) it's a bug in perl 5.8.4 that was fixed in 5.8.5, (b) it's a bug in the version of perl being distributed with Debian-sarge, or (c) there's something else going on that I don't understand. If it's a, then I guess I just post a notice on my web page saying my software is known not to work with 5.8.4. If it's b, then maybe I should report it as a bug to Debian. If it's c, then maybe it's a bug in perl that I should report, or...?

TIA!

Thanks, all, for your help! The suggestion about the BEGIN block was bang on -- I'd been assuming that Perl would just be checking the syntax, didn't realize it was doign the BEGIN blocks. The following turns out to be a somewhat more minimal example: 

  eval "use Audio::Data";

  my ($server,$sound);
  eval { # Don't crash and burn if they don't have Audio installed.
    my $silent = Audio::Data->new(rate=>44100.);
    my $shk = Audio::Data->new(rate=>44100.);
    my $delay = 0.06; # so it doesn't occur at the same instant as the
+ sound of the clicking key
    my $duration = 0.05;
    $silent->silence($delay);
    $shk->noise($duration,1.6);
    my $n = $shk->samples;
    my $attack_frac = .1;
    for (my $i=0; $i<=$n; $i++) {
      my $attack = 1.;
      if ($i<$n*$attack_frac) {$attack=$i/($n*$attack_frac)}
      my $tail = ($n-$i)/$n;
      my $env = $attack*$attack*$tail*$tail*$tail;
      $shk->[$i] *= $env;
    }
    $sound = Audio::Data->new(rate=>44100.);
    $sound = $silent . $shk;
  };

[download]
Interestingly, it seems to be very hard to take any code out of this without curing the bug. So the long and the short of it seems to be that it's a bug in Audio::Data.

In reply to bug in perl 5.8.4? by bcrowell2

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