I know its my error handling code and when I add a cut down version it is enough to generate the same error;

$SIG{__DIE__}  = \&log_die;

sub log_die {
 print @_;
}
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This is the full version, strange it has a die in it but the process doesn't!

sub log_die {
    return unless CRITICAL >= $PRIORITY;
    _log(_msg('critical',@_));
    die @_;
}
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