#13479: Core Lint issues during slowtest -------------------------------------+------------------------------------- Reporter: bgamari | Owner: nomeata Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 8.1 Resolution: | Keywords: JoinPoints Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: #10181 | Differential Rev(s): Phab:D3390 Wiki Page: | -------------------------------------+------------------------------------- Comment (by nomeata):
I’ll add a note, and not set the call arity annotation.
(Although it is debatable whether the simplifier is really innocent. The annotation is *true* even on join points; it is the simplifier that is stubbornly (but with good reason) refusing to eta-expand the join point!)
I have a patch that does this, but I don’t like it. The Call Arity analysis uses the `idCallArity` fields internally as well (in particular `callArityRecEnv` reads it), and if I don’t set the Call Arity annotation, then things can go wrong. Some refactoring of the analysis could avoid this, of course, but given that the call arity annotation is not *wrong* on join points, I do not see the advantage of special-casing join-points here. Also zapping the call arity information in the simplifier is the right thing to do in any case. So the current state of affair seems fine with me. I did add a Note, though. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13479#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler