#12130: ghc: panic! (the 'impossible' happened): find_tycon Block [] -------------------------------------+------------------------------------- Reporter: jeiea | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Template | Version: 8.0.1 Haskell | 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: -------------------------------------+------------------------------------- I just tried building yesod-simple template project with nightly-2016-05-29 snapshot and some extra-deps package, and it seems to fail due to {{{$(widgetFile ...)}}} yesod template haskell clause. It was same on linux and windows, and when I remove handler ghc fails at Application module (and seems also due to template haskell). {{{ ~/yt> stack build ... yt-0.0.0: configure Configuring yt-0.0.0... yt-0.0.0: build Preprocessing library yt-0.0.0... [1 of 9] Compiling Settings ( Settings.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Settings.o ) [2 of 9] Compiling Settings.StaticFiles ( Settings/StaticFiles.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Settings/StaticFiles.o ) [3 of 9] Compiling Import.NoFoundation ( Import/NoFoundation.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Import/NoFoundation.o ) [4 of 9] Compiling Foundation ( Foundation.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Foundation.o ) [5 of 9] Compiling Import ( Import.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Import.o ) [6 of 9] Compiling Handler.Common ( Handler/Common.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Handler/Common.o ) [7 of 9] Compiling Handler.Home ( Handler/Home.hs, .stack- work/dist/x86_64-linux/Cabal-1.24.0.0/build/Handler/Home.o ) ghc: panic! (the 'impossible' happened) (GHC version 8.0.1 for x86_64-unknown-linux): find_tycon Block [] Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug Completed 179 action(s). -- While building package yt-0.0.0 using: /home/jeiea/.stack/setup-exe-cache/x86_64-linux/setup-Simple- Cabal-1.24.0.0-ghc-8.0.1 --builddir=.stack- work/dist/x86_64-linux/Cabal-1.24.0.0 build lib:yt exe:yt --ghc-options " -ddump-hi -ddump-to-file" Process exited with code: ExitFailure 1 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12130 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler