#14253: Pattern match checker mistakenly concludes pattern match on pattern synonym is unreachable -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: | PatternSynonyms, | PatternMatchWarnings Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by dfeuer): Replying to [comment:7 RyanGlScott]:
I'm not sure why the original program would be any more honest, since it claims that matching on `TrFun` is inaccessible, right? That is, `Con` is to `MkT1` as `TrFun` is to `MkT2` as `Fun` is to `MkT2'` as `Dynamic` is to `S` as `dynApply` is to `u`. Or am I missing something?
Ah, simply because I didn't read it correctly. Ben came to this dishonest reduction from a perfectly honest example! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14253#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler