What's the canonical way to create platform-specific crates?
One could obviously put all the code in the crate in a platform-specific module, so that when it's built on an unsupported platform it just becomes an empty bin/lib. Or that the functions on unsupported platforms will panic in runtime informing the caller that the functions are unsupported. This would be extremely annoying, imo, so I hope this is discouraged.
How about panicing in build.rs on unsupported platforms?
But how would this affect crater runs? Is there some metadata one can use to signal to bulk builders to not even attempt to build on certain platforms?