-# Some filenames are AC_SUBSTed by the Gnulib macros, and thus we need to
-# prepend lib/ if and only if they're not empty. Unfortunately, make is not
-# powerful to do this, so we need to put this transformation into configure
-# itself by defining a new autoconf macro.
-
-my $lc = List::Compare->new('-u', '-a', \%sourcevars, \%allvars);
-my @vars = $lc->get_unique;
-