When you install the compiler, it makes a link in /usr/lib/ to the file of that name in the
compiler /lib directory, so you would expect this to point to the compiler you installed most recently. If you started out with a link to an old installation which you have trashed, it would be better to remove it. Evidently, this link would normally be owned by root, and you would have to su in order to remove it. Then you could replace it with a link to your currently installed one, or repeat your compiler installation.
