Apart from what sibling commenters say, the problem is that cmake's original syntax was introduced with the same glowing fanatism (over plain old Makefiles) tha

Apart from what sibling commenters say, the problem is that cmake's original syntax was introduced with the same glowing fanatism (over plain old Makefiles) that's now on display with cmake 3.0 (or is it 2.0?) over "old" cmake, making this enthusiasm not quite justifiable. If your old lib can't be build due to a deprecated build system, that's already the greatest possible disaster for a build system, as all your automatic tests etc might not run anymore and you lack a basis for releasing anything at that point. You need to setup an entire new project for recovery.