#15346: Core Lint error in GHC 8.6.1: From-type of Cast differs from type of enclosed expression -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler (Type | Version: 8.5 checker) | Resolution: | Keywords: TypeInType Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: #15419 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Richard Eisenberg <rae@…>): In [changeset:"af624071fa063158d6e963e171280676f9c0a0b0/ghc" af624071/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="af624071fa063158d6e963e171280676f9c0a0b0" Fix some casts. This fixes #15346, and is a team effort between Ryan Scott and myself (mostly Ryan). We discovered two errors related to FC's "push" rules, one in the TPush rule (as implemented in pushCoTyArg) and one in KPush rule (it shows up in liftCoSubstVarBndr). The solution: do what the paper says, instead of whatever random thoughts popped into my head as I was actually implementing. Also fixes #15419, which is actually the same underlying problem. Test case: dependent/should_compile/T{15346,15419}. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15346#comment:11> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler