#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: | -------------------------------------+------------------------------------- Comment (by simonpj):
I think that would just bring us back to using plain old VarSets, which we have already profiled.
Maybe so, but then I believe you are saying: * (a) `FV` is faster than `VarSet` * (b) None of (1), (2), (3) from comment:83 are responsible These can't both be true. We can successively transform `FV` into `VarSet` by changing (1), (2), (3), and at some point the perf must change, if (a) is true. Or have I misunderstood something? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14880#comment:89 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler