Hit the max nesting depth, but to reply about why, because winrt::import! is reading (arbitrary?) filesystem paths and there isn't an equivalent for build.rs emitting 'rerun-if-changed'.

So, neither cargo nor the compiler really know of the paths, and cannot accordingly rebuild the sources when they change.

Perhaps they can only change when a corresponding version cargo does know about changes, anyhow, bypassing the build/module system with a proc macro is probably not something to be done lightly.

Fun trick regarding the nesting depth, I believe that if you click on the comment permalink itself, it will still let you reply. Regardless, no worries :)

I was totally forgetting rerun-if-changed! This is indeed a barrier in the general case. I think that it doesn't affect this crate, but I am not 100% sure. Regardless, thank you!

Bah... This seems like exactly the kind of thing that makes dependency tracking, and sandboxing compilation harder.

Why? I'm not an expert here, but it seems basically the same to me.