#11710: Fusion of a simple listArray call is very fragile -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: patch Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2023 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari <ben@…>): In [changeset:"0db05941668814094c2b18b3d35e1deaed36c210/ghc" 0db05941/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="0db05941668814094c2b18b3d35e1deaed36c210" DsExpr: Rip out static/dynamic check in list desugaring Previously we would try to break explicit lists into a dynamic prefix and static tail and desugar the former into a `build` expression. Unfortunately, this heuristic resulted in surprising behavior (see #11710) and wasn't pulling its weight. Here we drop it (along with the `-fsimple-list-literals` flag), leaving only the list length heuristic to determine whether `build` or cons list desugaring should be used. Test Plan: Validate Reviewers: simonpj, austin Reviewed By: simonpj Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D2023 GHC Trac Issues: #11710 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11710#comment:7> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler