[JdeBP]

> The compiler works.

... but is too outdated to be capable of bootstrapping clang. There's very probably a long chain of bootstraps that would achieve it, but there's not a direct route.

> Will users be able to run their own Linux binaries on Windows?

The answer to that is easily determined from the demo video that Microsoft published. In it, Russ Alexander compiles a program with (Ubuntu binary) GCC and and runs it.

Its implicit int in the declaration of main() was jarring. (-: