Re: [GHC] #12430: TypeFamilyDependencies accepts invalid injectivity annotation

#12430: TypeFamilyDependencies accepts invalid injectivity annotation -------------------------------------+------------------------------------- Reporter: vagarenko | Owner: (none) Type: bug | Status: patch Priority: high | Milestone: Component: Compiler (Type | Version: 8.0.1 checker) | Keywords: Resolution: | InjectiveFamilies Operating System: Unknown/Multiple | Architecture: Type of failure: GHC accepts | Unknown/Multiple invalid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D5228 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari ): In [changeset:"26e81e90281685af37c8f2cf149c242b4039117a/ghc" 26e81e90/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="26e81e90281685af37c8f2cf149c242b4039117a" Fix #12430 by expanding type synonyms in injTyVarsOfType We weren't expanding type synonyms when determining the injective type variables of a type, leading to certain non-injective families being mistakenly labeled as injective (#12430). Easily fixed with a tactical use of `coreView`. Test Plan: make test TEST=T12430 Reviewers: bgamari, goldfire Reviewed By: goldfire Subscribers: goldfire, rwbarton, carter GHC Trac Issues: #12430 Differential Revision: https://phabricator.haskell.org/D5228 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12430#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler