#15862: Panic with promoted types that Typeable doesn't support -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.1 Resolution: | Keywords: Typeable 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): Unboxed sums, too: {{{#!hs {-# LANGUAGE TypeInType #-} {-# LANGUAGE UnboxedSums #-} module Bug where import Type.Reflection data Quux = MkQuux (# Bool | Int #) bar :: TypeRep MkQuux bar = typeRep }}} {{{ $ /opt/ghc/8.6.2/bin/ghc Bug.hs [1 of 1] Compiling Bug ( Bug.hs, Bug.o ) GHC error in desugarer lookup in Bug: attempting to use module ‘main:Bug’ (Bug.hs) which is not loaded ghc: panic! (the 'impossible' happened) (GHC version 8.6.2 for x86_64-unknown-linux): initDs }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15862#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler