#15019: Fix performance regressions from #14737 -------------------------------------+------------------------------------- Reporter: tdammers | Owner: (none) Type: bug | Status: patch Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #14737 | Differential Rev(s): phab:D4635 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari <ben@…>): In [changeset:"d92c7556501a4cdeb7d269c4624992c94d9b3b8b/ghc" d92c755/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="d92c7556501a4cdeb7d269c4624992c94d9b3b8b" Fix performance regressions from #14737 See #15019. When removing an unnecessary type equality check in #14737, several regression tests failed. The cause was that some coercions that are actually Refl coercions weren't passed in as such, which made the equality check needlessly complex (Refl coercions can be discarded in this particular check immediately, without inspecting the types at all). We fix that, and get additional performance improvements for free. Reviewers: goldfire, bgamari, simonpj Reviewed By: bgamari, simonpj Subscribers: simonpj, thomie, carter Differential Revision: https://phabricator.haskell.org/D4635 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15019#comment:23> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler