#14880: GHC panic: updateRole -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 8.2.2 checker) | Resolution: | Keywords: TypeInType Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: #15076 | Differential Rev(s): Phab:D4769 Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): `poly_merge1` is likely coming from the `mergeWithKey'` function from `Data.IntMap` (which `unionVarSet` is implemented in terms of), as it has a helper function named `merge1`. The question, I suppose, is //which// use(s) of `unionVarSet` are problematic. There are at least a couple new uses of `unionVarSet` in Phab:D4769: * In `mapUnionVarSetSet`, which is used in the pivotal `closeOverKinds` function * Directly in `closeOverKinds` itself * In `nonDetCmpTypes` -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14880#comment:45 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler