One of my programs started giving me this error this morning. Mondays, don't ya just luv em?

It's a complicated program and I'd made some changes but none in the part of the program that's crashing. And I don't think any of my code does anything that's likely to provoke this kind of behaviour. I've added some debug statements at the point of failure and this stanza: 

  $swiss = 'P07445';
  warn "swiss='$swiss'\n";
  my @rer;
  $rer[0] = $swiss =~ /^\p{IsAlpha}/;

[download]

produces: 

  swiss='P07445'
  panic: Something requested a negative number of bytes of malloc.

[download]

but only if I run it in the debugger. If I let the program run freestanding, it works. Sadly my original program crashes if I let it run.

Has anybody seen this problem before or have any ideas how to debug it? Presumably something is stamping on memory somewhere but what? I'm using perl 5.8.6

Thanks, Dave

In reply to panic: Something requested a negative number of bytes of malloc by Dave Howorth

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