I see that databases/db/buildlink2.mk does:

CPPFLAGS+=                      ${BUILDLINK_CPPFLAGS.db}

And various other buildlink2.mk do the same (like libyahoo, bobobo,
MesaLib, and so on).

But db3, db4, and gdbm do not.

When should CPPFLAGS add the BUILDLINK_CPPFLAGS? And when should it not?

   Jeremy C. Reed
   http://bsd.reedmedia.net/