I think metaprogram expansion has to be considered part of compiling. You have sourcecode, you need machinecode. If the lang says that the process of getting there requires running some metaprogram, so be it.

For Rust I think the type system itself is probably enough though even without that. If neither type checking or metaprogramming are part of compiling, I think your (for hypothetical you) definition of compiling is a bit too restrictive.