Program Repair Shop

"Can't happen"

This is the second kind of "can't happen":

     354  foreach $filesz (sort { $b <=> $a } keys %names_by_size)
        ...
     364      if (!defined ($filesz))  # this should never happen, but handle it anyway
     365      {
     366        print "$num_files_this_size files of UNDEF:\n    ",
     367            join ("\n    ", @{$names_by_size{$filesz}}), "\n";
     368        next;
     369      }
     370

$filesz is a hash key
Hash keys are always strings and so are always defined

        % perl -le '$h{undef}=1; ($k)=keys %j; print "defined" if defined $k'
        defined

All this code is doing is checking to see if the Perl implementation has changed
It is not any more useful than this:

        if (2 + 2 != 4) {   # this should never happen, but handle it anyway
          ...
        }

I have removed it