#13233: typePrimRep panic while compiling GHC with profiling -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: highest | Milestone: 8.2.1 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): FWIW, here is a much easier way to trigger this panic that doesn't require profiling: {{{#!hs {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TypeInType #-} {-# LANGUAGE UnboxedTuples #-} module Bug where import GHC.Exts (TYPE) class Foo (a :: TYPE rep) where bar :: forall (b :: TYPE rep2). (a -> a -> b) -> a -> a -> b baz :: forall (a :: TYPE rep). Foo a => a -> a -> (# a, a #) baz = bar (#,#) }}} {{{ $ ~/Software/ghc/inplace/bin/ghc-stage2 Bug.hs [1 of 1] Compiling Bug ( Bug.hs, Bug.o ) ghc-stage2: panic! (the 'impossible' happened) (GHC version 8.3.20170322 for x86_64-unknown-linux): runtimeRepPrimRep typePrimRep (a_12 :: TYPE k0_10) k0_10 Call stack: CallStack (from HasCallStack): prettyCurrentCallStack, called at compiler/utils/Outputable.hs:1191:58 in ghc:Outputable callStackDoc, called at compiler/utils/Outputable.hs:1195:37 in ghc:Outputable pprPanic, called at compiler/simplStg/RepType.hs:360:5 in ghc:RepType }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13233#comment:24 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler