swift

43075bff - [ParseableInterface] Honor -track-system-dependencies when caching

[ParseableInterface] Honor -track-system-dependencies when caching One interesting thing here is that the decision of whether or not to track system dependencies ends up going into the cache key for a swiftmodule built from a parseable interface, because it affects that module's up-to-date check. If we didn't include -track-system-dependencies in the cache key, we could end up tracking system dependencies for some modules but not others in the same build. There's a bit of a bug here where they're /not/ honored if the top-level invocation isn't tracking /any/ dependencies, but given how uncommon this flag is in practice that's probably okay for now. Still TODO: honor this for -build-swiftmodule-from-parseable-interface as well. That's currently not tracking dependencies at all and it probably should.