unless(defined($pkg)) {
      # This *shouldn't* happen.
      if (%Internal) {
        local %Internal;
        $i = long_error_loc();
        last;
      }
      else {
        # OK, now I am irritated.
        return 2;
      }
    }
    redo if $CarpInternal{$pkg};
    redo unless 0 > --$lvl;
    redo if $Internal{$pkg};
  }
  return $i - 1;
}


sub longmess_heavy {
  return @_ if ref($_[0]); # don't break references as exceptions
  my $i = long_error_loc();
  return ret_backtrace($i, @_);
}

# Returns a full stack backtrace starting from where it is
# told.
sub ret_backtrace {
  my ($i, @error) = @_;
  my $mess;
  my $err = join '', @error;
  $i++;

  my $tid_msg = '';
  if (defined &Thread::tid) {
    my $tid = Thread->self->tid;
    $tid_msg = " thread $tid" if $tid;
  }

  my %i = caller_info($i);
  $mess = "$err at $i{file} line $i{line}$tid_msg\n";

  while (my %i = caller_info(++$i)) {
      $mess .= "\t$i{sub_name} called at $i{file} line $i{line}$tid_msg\n";
  }
  
  return $mess;
}

sub ret_summary {
  my ($i, @error) = @_;
  my $err = join '', @error;
  $i++;

  my $tid_msg = '';
  if (defined &Thread::tid) {
    my $tid = Thread->self->tid;
    $tid_msg = " thread $tid" if $tid;
  }

  my %i = caller_info($i);
  return "$err at $i{file} line $i{line}$tid_msg\n";
}


sub short_error_loc {
  my $cache;
  my $i = 1;
  my $lvl = $CarpLevel;
  {
    my $called = caller($i++);
    my $caller = caller($i);
    return 0 unless defined($caller); # What happened?
    redo if $Internal{$caller};
    redo if $CarpInternal{$called};
    redo if trusts($called, $caller, $cache);
    redo if trusts($caller, $called, $cache);
    redo unless 0 > --$lvl;
  }
  return $i - 1;
}

sub shortmess_heavy {
  return longmess_heavy(@_) if $Verbose;
  return @_ if ref($_[0]); # don't break references as exceptions
  my $i = short_error_loc();
  if ($i) {
    ret_summary($i, @_);
  }
  else {
    longmess_heavy(@_);
  }
}

# If a string is too long, trims it with ...
sub str_len_trim {
  my $str = shift;
  my $max = shift || 0;
  if (2 < $max and $max < length($str)) {