#11600: Panic (ASSERT failed) in compiler/types/TyCoRep.hs:1939 -------------------------------------+------------------------------------- Reporter: hvr | Owner: Type: bug | Status: new Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by hvr): Replying to [comment:8 simonpj]:
Thanks Herbert. Since you have a working setup, Could you add a `HasCallStack` to `Subst.substCo` to extend the trace upwards a bit? (It may take another couple of layers.)
Here's a couple more CallStack context (do you need more)? {{{ ghc-stage1: panic! (the 'impossible' happened) (GHC version 8.1.20160219 for x86_64-unknown-linux): ASSERT failed! CallStack (from HasCallStack): assertPprPanic, called at compiler/types/TyCoRep.hs:1932:56 in ghc:TyCoRep checkValidSubst, called at compiler/types/TyCoRep.hs:2076:17 in ghc:TyCoRep substCo, called at compiler/coreSyn/CoreSubst.hs:607:20 in ghc:CoreSubst substCo, called at compiler/coreSyn/CoreSubst.hs:382:39 in ghc:CoreSubst go, called at compiler/coreSyn/CoreSubst.hs:374:5 in ghc:CoreSubst subst_expr, called at compiler/coreSyn/CoreSubst.hs:370:33 in ghc:CoreSubst substExpr, called at compiler/coreSyn/CoreUnfold.hs:158:27 in ghc:CoreUnfold specUnfolding, called at compiler/specialise/Specialise.hs:1312:32 in ghc:Specialise }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11600#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler