#15537: Panic when building Crucible -------------------------------------+------------------------------------- Reporter: siddharthist | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 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: -------------------------------------+------------------------------------- I've encountered a panic, which GHC has asked me to report: {{{ [19 of 21] Compiling Lang.Crucible.LLVM.Translation ( src/Lang/Crucible/LLVM/Translation.hs, dist/build/Lang/Crucible/LLVM/Translation.p_o ) <no location info>: error: ghc: panic! (the 'impossible' happened) (GHC version 8.4.3 for x86_64-unknown-linux): isUnliftedType r_a4Zsg :: TYPE rep_a4Zsf Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in ghc:Outputable pprPanic, called at compiler/types/Type.hs:1939:10 in ghc:Type Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} This was when compiling [https://github.com/GaloisInc/crucible/tree/master /crucible-llvm crucible-llvm] revision 186mfb7wlz with GHC 8.4.3. I'm building in Nix with a sandbox, so this should be easily reproducible. The Nix files are available here: https://github.com/siddharthist/galois- haskell-nix/tree/ghc-bug. Just run nix-build -A haskellPackages.crucible- llvm. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15537 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler