#14895: STG CSE makes dead binders undead -------------------------------------+------------------------------------- Reporter: hsyl20 | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Debugging | Unknown/Multiple information is incorrect | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Delicate! Can you add a Note in `StgCSE` to explain? Actually it'd be more correct to do this in `StgCSE` * Zap the dead-binder flag on most case-binders (explaining why) * But not the ones for primop applications (because they aren't CSE'd, I think you are saying). That way they never lie. We'd still need a note to say that dead-ness is now a bit pessimistic; but the code gen doesn't use it (except in a narrow case) so the pessimism doesn't matter. Not hard to do. Thanks -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14895#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler