Re: [GHC] #11474: incorrect redundant-constraints warning

#11474: incorrect redundant-constraints warning -------------------------------------+------------------------------------- Reporter: hvr | Owner: (none) Type: bug | Status: patch Priority: normal | Milestone: 8.8.1 Component: Compiler (Type | Version: 8.0.1-rc1 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Incorrect | Test Case: warning at compile-time | tests/typecheck/should_compile/T11474.hs Blocked By: | Blocking: Related Tickets: #10100 | Differential Rev(s): Phab:D4739 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones ): In [changeset:"4293a80a3ea835412737911bcb2a6703e9af378b/ghc" 4293a80a/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="4293a80a3ea835412737911bcb2a6703e9af378b" Accommodate API change in transSuperClasses In this patch commit 6eabb6ddb7c53784792ee26b1e0657bde7eee7fb Author: Simon Peyton Jones Date: Tue Dec 15 14:26:13 2015 +0000 Allow recursive (undecidable) superclasses I changed (transSuperClasses p) to return only the superclasses of p, but not p itself. (Previously it always returned p as well.) The use of transSuperClasses in TcErrors.warnRedundantConstraints really needs 'p' in the result -- but I faild to fix this call site, and instead crippled the test for Trac #10100. This patch sets things right * Accomodates the API change * Re-enables T10100 * And thereby fixes Trac #11474 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11474#comment:11 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler