#12899: ghc panics at random places with -jX -------------------------------------+------------------------------------- Reporter: pacak | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by pacak): After recompilation in devel2 mode, one of the panics: {{{ <no location info>: error: ghc: panic! (the 'impossible' happened) (GHC version 8.1.20161206 for x86_64-unknown-linux): applyTypeToArgs Expression: $fDataFixity_$cgmapQ @ (Exchange ByteString ByteString) @ Identity ($fProfunctorExchange @ ByteString @ ByteString) $fFunctorIdentity Type: forall u. (forall d. Data d => d -> u) -> Fixity -> [u] Args: [TYPE: Exchange ByteString ByteString, TYPE: Identity, $fProfunctorExchange @ ByteString @ ByteString, $fFunctorIdentity] Call stack: CallStack (from HasCallStack): prettyCurrentCallStack, called at compiler/utils/Outputable.hs:1114:58 in ghc:Outputable callStackDoc, called at compiler/utils/Outputable.hs:1118:37 in ghc:Outputable pprPanic, called at compiler/coreSyn/CoreUtils.hs:181:14 in ghc:CoreUtils Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12899#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler