#11371: Bogus in-scope set in substitutions -------------------------------------+------------------------------------- Reporter: simonpj | Owner: niteria Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #11360 | Differential Rev(s): phab:D1792, Wiki Page: | phab:D1801, phab:D1802 -------------------------------------+------------------------------------- Comment (by thomie): This commit causes the following Travis failures with DEBUG=YES: {{{ Unexpected failures: ../../libraries/base/tests/IO hClose002 [exit code non-0] (normal) ../../libraries/base/tests/IO hClose003 [exit code non-0] (normal) ../../libraries/base/tests/IO hDuplicateTo001 [exit code non-0] (normal) }}} See https://s3.amazonaws.com/archive.travis-ci.org/jobs/105899161/log.txt Here is one of them: {{{ =====> hClose002(normal) 4736 of 5007 [0, 0, 0] Compile failed (status 256) errors were: [1 of 1] Compiling Main ( hClose002.hs, hClose002.o ) ghc-stage2: panic! (the 'impossible' happened) (GHC version 8.1.20160130 for x86_64-unknown-linux): ASSERT failed! CallStack (from ImplicitParams): assertPprPanic, called at compiler/types/TyCoRep.hs:1903:56 in ghc:TyCoRep checkValidSubst, called at compiler/types/TyCoRep.hs:2047:17 in ghc:TyCoRep substCo, called at compiler/basicTypes/MkId.hs:698:28 in ghc:MkId in_scope InScope {} tenv [a1oW :-> dev_a1Z8, a1oX :-> enc_state_a1Z9, a1oY :-> dec_state_a1Za] tenvFVs [a1Z8 :-> dev_a1Z8, a1Z9 :-> enc_state_a1Z9, a1Za :-> dec_state_a1Za] cenv [] cenvFVs [] tys [] cos [N:IORef[0] <Buffer Word8>_N] }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11371#comment:24 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler