Warning: libtool versus gcc versus port-building

[walt]

I just wasted yet another day running down libtool problems, so
I hope maybe this will save someone else the same headaches:
When switching compiler versions (as I just did by picking
gcc34 as my default) libtool will cause file-not-found-errors
by using paths targeted to the old compiler.  (More specifically,
libtool will assume that you are using the same compiler you
used when you installed the libtool port.)
Therefore, each time you switch compilers you must re-install
the libtool port before building any other port that uses
libtool (which is most all, I think).
These comments apply to libtool15 specifically, and maybe to
13 and 14 also but I'm not certain about that.  I just deleted
13 and 14 rather than re-installing them.  (I enjoyed that ;o)