#13994: STG lint failure on master -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: 8.4.1 Component: Compiler | Version: 8.3 Resolution: | Keywords: stg-lint Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4396 Wiki Page: | -------------------------------------+------------------------------------- Comment (by osa1): After Phab:D4396 it's failing in `GHC.Integer.Type`. This time the problem is we have in scrutinee position an unboxed tuple (pair) with `State#` as second argument, but binder becomes `Unit#` after unarise becuase `State#` has no representation in runtime. Error message: {{{ ghc-stage1: panic! (the 'impossible' happened) (GHC version 8.5.20180207 for x86_64-unknown-linux): ASSERT failed! dataConInstArgTys Unit# [k0_10, a_11] ['TupleRep '[], 'LiftedRep, State# s_a2Hq, a_a2Hr] Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in ghc:Outputable pprPanic, called at compiler/utils/Outputable.hs:1206:5 in ghc:Outputable assertPprPanic, called at compiler/basicTypes/DataCon.hs:1255:76 in ghc:DataCon Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} I look into this in more detail later. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13994#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler