perl -wle 'BEGIN { $SIG{__DIE__} = sub { print "Catched SIGDIE: @_";exit(-1) }} use utf8; /^\w$/;'

##</code><code>##

Catched SIGDIE: Can't locate object method "IsWord" via package "main" (perhaps you forgot to load "main"?) at /usr/local/lib/perl5/5.6.1/utf8_heavy.pl line 30.