Description
In #479 (comment) , warnings are emitted for modules that are defined via preprocessor. Since module name -> file path resolution is used for knowing when to rebuild, I think there is likely a rebuild issue here.
Not sure how to unambiguously resolve module names to files that do not have .hs or .lhs extensions, though. A hack could be to assume that it is the correct file if the name matches, ignoring the extension, and if it's listed in extra-source-files as suggested by the warning text. Currently it seems like extra-source-files is not taken into account here. So, either the warning text should be fixed or the behavior should make it so that its suggestion works.
Repro is at https://github.com/adituv/protobuf/tree/testpreprocess