#13710: panic with boot and -jX -------------------------------------+------------------------------------- Reporter: pacak | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1-rc2 Resolution: | Keywords: hs-boot 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 pacak): Panic in rc2, successfull compilation in 8.0 and 7.10 {{{ % cat A.hs {-# LANGUAGE RecordWildCards #-} module A where import B type E = () yay :: Maybe () yay = do H{..} <- undefined undefined }}} {{{ % cat A.hs-boot module A ( E ) where type E = () }}} {{{ % cat B.hs module B where import {-# SOURCE #-} A data F a = F a type G = F (Maybe E) data H = H { h :: {-# UNPACK #-} !G } }}} rc2, -j1 {{{ % rm *.hi* *.o* ; ghc -j1 -O2 A.hs [1 of 3] Compiling A[boot] ( A.hs-boot, A.o-boot ) [2 of 3] Compiling B ( B.hs, B.o ) [3 of 3] Compiling A ( A.hs, A.o ) ghc: panic! (the 'impossible' happened) (GHC version 8.2.0.20170503 for x86_64-unknown-linux): tcIfaceGlobal (local): not found You are in a maze of twisty little passages, all alike. While forcing the thunk for TyThing E which was lazily initialized by initIfaceCheck typecheckLoop, I tried to tie the knot, but I couldn't find E in the current type environment. If you are developing GHC, please read Note [Tying the knot] and Note [Type-checking inside the knot]. Consider rebuilding GHC with profiling for a better stack trace. Contents of current type environment: [] Call stack: CallStack (from HasCallStack): prettyCurrentCallStack, called at compiler/utils/Outputable.hs:1134:58 in ghc:Outputable callStackDoc, called at compiler/utils/Outputable.hs:1138:37 in ghc:Outputable pprPanic, called at compiler/iface/TcIface.hs:1689:23 in ghc:TcIface Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} rc2, -j2 - note - error message is slightly different + it's in color {{{ % rm *.hi* *.o* ; ghc -j2 -O2 A.hs [1 of 3] Compiling A[boot] ( A.hs-boot, A.o-boot ) [2 of 3] Compiling B ( B.hs, B.o ) [3 of 3] Compiling A ( A.hs, A.o ) <no location info>: error: ghc: panic! (the 'impossible' happened) (GHC version 8.2.0.20170503 for x86_64-unknown-linux): tcIfaceGlobal (local): not found You are in a maze of twisty little passages, all alike. While forcing the thunk for TyThing E which was lazily initialized by initIfaceCheck typecheckLoop, I tried to tie the knot, but I couldn't find E in the current type environment. If you are developing GHC, please read Note [Tying the knot] and Note [Type-checking inside the knot]. Consider rebuilding GHC with profiling for a better stack trace. Contents of current type environment: [] Call stack: CallStack (from HasCallStack): prettyCurrentCallStack, called at compiler/utils/Outputable.hs:1134:58 in ghc:Outputable callStackDoc, called at compiler/utils/Outputable.hs:1138:37 in ghc:Outputable pprPanic, called at compiler/iface/TcIface.hs:1689:23 in ghc:TcIface Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} ghc 8.0: {{{ % rm *.hi* *.o* ; ghc -j1 -O2 A.hs [1 of 3] Compiling A[boot] ( A.hs-boot, A.o-boot ) [2 of 3] Compiling B ( B.hs, B.o ) [3 of 3] Compiling A ( A.hs, A.o ) }}} {{{ % rm *.hi* *.o* ; ghc -j2 -O2 A.hs [1 of 3] Compiling A[boot] ( A.hs-boot, A.o-boot ) [2 of 3] Compiling B ( B.hs, B.o ) [3 of 3] Compiling A ( A.hs, A.o ) }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13710#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler