Bug#624689: perl: segfaults (dereferencing a null pointer) while evaluating a pattern match

[Reini Urban]

The bug is valid, and already fixed since 5.22 or so.
To repro it you need to fix the order of global destruction, e.g by PERL_HASH_SEED=0

The problem is that the unicode helper swashes were already destroyed when the regex 
inside the DESTROY handler, run during global destruction, requested a re-load of the unicode swashes.

The fix for the user is to replace \w by [a-zA-Z0-9_], to avoid triggering the invalid swash_init during global destruction.
or use the new /a flag with newer perls (since 5.14), to avoid re-loading unicode during global destruction.


Reini Urban
rurban at cpan.org