#13022: Pattern Synonyms using other synonyms causes ghc panic -------------------------------------+------------------------------------- Reporter: AveryGlitch | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Linux Architecture: x86_64 | Type of failure: Compile-time (amd64) | crash or panic Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Here's a (somewhat) minimal example: {{{#!hs {-# LANGUAGE PatternSynonyms #-} data Some = Thing Int Int pattern A x = Thing x 0 pattern B x = Thing x 1 pattern C x = Thing x 2 pattern D = C 3 }}} And here's what happened when I tried to load this into ghci: {{{ *Main> :l ghc_bug.hs [1 of 1] Compiling Main ( ghc_bug.hs, interpreted ) ghc: panic! (the 'impossible' happened) (GHC version 8.0.1 for x86_64-unknown-linux): kindPrimRep.go rep_a3fP Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13022 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler