diff -rupN calf-0.90.0.org/src/makerdf.cpp calf-0.90.0/src/makerdf.cpp
--- calf-0.90.0.org/src/makerdf.cpp	2017-07-04 17:41:59.000000000 -0400
+++ calf-0.90.0/src/makerdf.cpp	2018-03-07 23:28:56.745358556 -0500
@@ -676,7 +676,7 @@ int main(int argc, char *argv[])
                     fprintf(stderr, "calfmakerdf: Data directory must not be empty\n");
                     exit(1);
                 }
-                if (pkglibdir_path[path_prefix.length() - 1] != '/')
+                if (pkglibdir_path[pkglibdir_path.length() - 1] != '/')
                     pkglibdir_path += '/';
                 break;
 #endif