Need to add tests that fail to compile. q.v. https://ibob.bg/blog/2022/10/04/testing-build-failure-with-cmake/ https://stackoverflow.com/questions/30155619/expected-build-failure-tests-in-cmake/50665823#50665823 https://gist.github.com/tim-welch/00e07dc57864de36739945156e4049e2 https://stackoverflow.com/questions/24692820/how-to-test-the-static-assert-in-my-library-with-cmake Some of the docs linked mention working around old cmake issues, which we should *not* do. The approach in ibob.bg looks somewhat compatible with how `lit` is working, in that it's confirming the reason for failing to compile.