#14880: GHC panic: updateRole -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: goldfire Type: bug | Status: new Priority: normal | Milestone: 8.8.1 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: | Phab:D5141 -------------------------------------+------------------------------------- Comment (by simonpj):
Hence, we should not move the closing-over-kinds part at all, and instead just modify the TyVar branch of ty_co_vars_of_type so that it handles each variable it encounters exactly once (comment:123)
Correct, that's what I'm suggesting.
I had been implementing Simon's suggestion from comment:122, and at least while still using mapUnionVarSet, I'm still getting regressions on 4 tests,
I'd be surprised if you still got regressions if you adopted the more efficient `closeOverKinds` from comment:122. But (a) I've been surprised many times by this zombie and (b) I think comment:123 is better anyway. TL;DR: do comment:123. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14880#comment:128 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler