{"action":"created","issue":{"url":"https://api.github.com/repos/dart-lang/sdk/issues/24713","labels_url":"https://api.github.com/repos/dart-lang/sdk/issues/24713/labels{/name}","comments_url":"https://api.github.com/repos/dart-lang/sdk/issues/24713/comments","events_url":"https://api.github.com/repos/dart-lang/sdk/issues/24713/events","html_url":"https://github.com/dart-lang/sdk/issues/24713","id":113066816,"number":24713,"title":"New 'dynamic' does not extend 'A' warning","user":{"login":"Hixie","id":551196,"avatar_url":"https://avatars.githubusercontent.com/u/551196?v=3","gravatar_id":"","url":"https://api.github.com/users/Hixie","html_url":"https://github.com/Hixie","followers_url":"https://api.github.com/users/Hixie/followers","following_url":"https://api.github.com/users/Hixie/following{/other_user}","gists_url":"https://api.github.com/users/Hixie/gists{/gist_id}","starred_url":"https://api.github.com/users/Hixie/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/Hixie/subscriptions","organizations_url":"https://api.github.com/users/Hixie/orgs","repos_url":"https://api.github.com/users/Hixie/repos","events_url":"https://api.github.com/users/Hixie/events{/privacy}","received_events_url":"https://api.github.com/users/Hixie/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/dart-lang/sdk/labels/Analyzer-StrongMode","name":"Analyzer-StrongMode","color":"eeeeee"},{"url":"https://api.github.com/repos/dart-lang/sdk/labels/Area-Analyzer","name":"Area-Analyzer","color":"ededed"},{"url":"https://api.github.com/repos/dart-lang/sdk/labels/Priority-Medium","name":"Priority-Medium","color":"ededed"},{"url":"https://api.github.com/repos/dart-lang/sdk/labels/Type-Defect","name":"Type-Defect","color":"ededed"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":5,"created_at":"2015-10-23T17:45:45Z","updated_at":"2015-10-23T19:41:43Z","closed_at":null,"body":"When upgrading the SDK to 1.13.0-dev.7.1, a new warning started appearing:\r\n\r\n```dart\r\nclass A { }\r\nclass M<T extends A> { }\r\nclass Q { bool test(M arg) => arg is M<dynamic>; }\r\nvoid main() { }\r\n```\r\n\r\n```\r\nAnalyzing [test.dart]...\r\n[warning] 'dynamic' does not extend 'A' (test.dart, line 4, col 40)\r\n1 error found.\r\n```\r\n\r\nIs this intended?\r\n\r\nI'm happy to replace `dynamic` with `A` which is probably better anyway (and would, in unchecked mode, reject things like M<int>, which the current code would not). Just curious if this is intended."},"comment":{"url":"https://api.github.com/repos/dart-lang/sdk/issues/comments/150672188","html_url":"https://github.com/dart-lang/sdk/issues/24713#issuecomment-150672188","issue_url":"https://api.github.com/repos/dart-lang/sdk/issues/24713","id":150672188,"user":{"login":"Hixie","id":551196,"avatar_url":"https://avatars.githubusercontent.com/u/551196?v=3","gravatar_id":"","url":"https://api.github.com/users/Hixie","html_url":"https://github.com/Hixie","followers_url":"https://api.github.com/users/Hixie/followers","following_url":"https://api.github.com/users/Hixie/following{/other_user}","gists_url":"https://api.github.com/users/Hixie/gists{/gist_id}","starred_url":"https://api.github.com/users/Hixie/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/Hixie/subscriptions","organizations_url":"https://api.github.com/users/Hixie/orgs","repos_url":"https://api.github.com/users/Hixie/repos","events_url":"https://api.github.com/users/Hixie/events{/privacy}","received_events_url":"https://api.github.com/users/Hixie/received_events","type":"User","site_admin":false},"created_at":"2015-10-23T19:41:43Z","updated_at":"2015-10-23T19:41:43Z","body":"We do sometimes instantiate `Z` with `dynamic`. (When we do, we don't use `test()` or anything else depending on `V`.)"}}