Yes good point. Though I think most features can be tested without running a program -- e.g. testing if a library function exists or has a certain signature.

Yes good point. Though I think most features can be tested without running a program -- e.g. testing if a library function exists or has a certain signature. I think embedded toolchains use plain makefiles because they tend to fork code rather than upstream changes. And that is due to the ship-it-and-forget-it mindset of embedded companies that is well known among open source maintainers.