{"action":"created","issue":{"url":"https://api.github.com/repos/rust-lang/rust/issues/43018","repository_url":"https://api.github.com/repos/rust-lang/rust","labels_url":"https://api.github.com/repos/rust-lang/rust/issues/43018/labels{/name}","comments_url":"https://api.github.com/repos/rust-lang/rust/issues/43018/comments","events_url":"https://api.github.com/repos/rust-lang/rust/issues/43018/events","html_url":"https://github.com/rust-lang/rust/issues/43018","id":240037429,"number":43018,"title":"Borrow checking time regression from stable to nightly","user":{"login":"jonhoo","id":176295,"avatar_url":"https://avatars2.githubusercontent.com/u/176295?v=4","gravatar_id":"","url":"https://api.github.com/users/jonhoo","html_url":"https://github.com/jonhoo","followers_url":"https://api.github.com/users/jonhoo/followers","following_url":"https://api.github.com/users/jonhoo/following{/other_user}","gists_url":"https://api.github.com/users/jonhoo/gists{/gist_id}","starred_url":"https://api.github.com/users/jonhoo/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/jonhoo/subscriptions","organizations_url":"https://api.github.com/users/jonhoo/orgs","repos_url":"https://api.github.com/users/jonhoo/repos","events_url":"https://api.github.com/users/jonhoo/events{/privacy}","received_events_url":"https://api.github.com/users/jonhoo/received_events","type":"User","site_admin":false},"labels":[{"id":262252840,"url":"https://api.github.com/repos/rust-lang/rust/labels/regression-from-stable-to-stable","name":"regression-from-stable-to-stable","color":"FF309F","default":false}],"state":"open","locked":false,"assignee":null,"assignees":[],"milestone":null,"comments":1,"created_at":"2017-07-02T22:02:04Z","updated_at":"2017-07-23T15:35:52Z","closed_at":null,"body":"The compile time for the following code has increased significantly since the last stable:\r\n```rust\r\nextern crate futures;\r\nuse futures::{future, IntoFuture, Future};\r\nfn main() {\r\n    let t: std::result::Result<(), ()> = Ok(());\r\n    let f = t\r\n            .into_future()\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()))\r\n            .and_then(|_| future::ok(()));\r\n    f.wait();\r\n}\r\n```\r\nIgnoring the fact that the `translation`phase takes forever (tracked in #38528), the `borrow checking` phase now takes orders of magnitude longer than on the last stable:\r\n```console\r\n$ cargo +stable rustc -- -Z time-passes | grep \"borrow checking\"\r\ntime: 0.000; rss: 88MB  borrow checking                                                                                                                                                                                                                                      $ cargo +nightly rustc -- -Z time-passes | grep \"borrow checking\"\r\ntime: 1.173; rss: 101MB borrow checking\r\n```"},"comment":{"url":"https://api.github.com/repos/rust-lang/rust/issues/comments/317261527","html_url":"https://github.com/rust-lang/rust/issues/43018#issuecomment-317261527","issue_url":"https://api.github.com/repos/rust-lang/rust/issues/43018","id":317261527,"user":{"login":"alexcrichton","id":64996,"avatar_url":"https://avatars1.githubusercontent.com/u/64996?v=4","gravatar_id":"","url":"https://api.github.com/users/alexcrichton","html_url":"https://github.com/alexcrichton","followers_url":"https://api.github.com/users/alexcrichton/followers","following_url":"https://api.github.com/users/alexcrichton/following{/other_user}","gists_url":"https://api.github.com/users/alexcrichton/gists{/gist_id}","starred_url":"https://api.github.com/users/alexcrichton/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/alexcrichton/subscriptions","organizations_url":"https://api.github.com/users/alexcrichton/orgs","repos_url":"https://api.github.com/users/alexcrichton/repos","events_url":"https://api.github.com/users/alexcrichton/events{/privacy}","received_events_url":"https://api.github.com/users/alexcrichton/received_events","type":"User","site_admin":false},"created_at":"2017-07-23T15:35:52Z","updated_at":"2017-07-23T15:35:52Z","body":"Looks like this regression has snuck into 1.19.0 by accident :("}}
{"actor":{"display_login":"alexcrichton"}}