#7911: The following code makes ghc panic -----------------------------+---------------------------------------------- Reporter: guest | Owner: Type: bug | Status: new Priority: normal | Component: Compiler Version: 7.4.2 | Keywords: Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: None/Unknown | Blockedby: Blocking: | Related: -----------------------------+---------------------------------------------- This code has a bug (lowercase show instead of uppercase Show), but it shouldn't make the compiler crash. {{{ {-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, FlexibleContexts, UndecidableInstances #-} data Person = SnowWhite | Dwarf Int deriving (show, Eq, Ord) }}} Result: {{{ ghc: panic! (the 'impossible' happened) (GHC version 7.4.2 for i386-unknown-mingw32): nameModule show{tv avGJ} Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7911 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler