{"action":"closed","number":24056,"pull_request":{"url":"https://api.github.com/repos/rust-lang/rust/pulls/24056","id":32631662,"html_url":"https://github.com/rust-lang/rust/pull/24056","diff_url":"https://github.com/rust-lang/rust/pull/24056.diff","patch_url":"https://github.com/rust-lang/rust/pull/24056.patch","issue_url":"https://api.github.com/repos/rust-lang/rust/issues/24056","number":24056,"state":"closed","locked":false,"title":"Prefer ObjectCandidate to ImplCandidate if both apply","user":{"login":"nikomatsakis","id":155238,"avatar_url":"https://avatars.githubusercontent.com/u/155238?v=3","gravatar_id":"","url":"https://api.github.com/users/nikomatsakis","html_url":"https://github.com/nikomatsakis","followers_url":"https://api.github.com/users/nikomatsakis/followers","following_url":"https://api.github.com/users/nikomatsakis/following{/other_user}","gists_url":"https://api.github.com/users/nikomatsakis/gists{/gist_id}","starred_url":"https://api.github.com/users/nikomatsakis/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nikomatsakis/subscriptions","organizations_url":"https://api.github.com/users/nikomatsakis/orgs","repos_url":"https://api.github.com/users/nikomatsakis/repos","events_url":"https://api.github.com/users/nikomatsakis/events{/privacy}","received_events_url":"https://api.github.com/users/nikomatsakis/received_events","type":"User","site_admin":false},"body":"If we find a blanket impl for `Trait` but we're matching on an object `Trait`, prefer the object (I think we could perhaps go either way, but this seems safer). Also give a nice error for attempts to manually `impl Trait for Trait`, since they will be ineffectual.\r\n\r\nThis fixes the problems around ambiguity ICEs relating to `Any` and `MarkerTrait` that were cropping up all over the place. There may still be similar ICEs reported in #21756 that this PR does not address.\r\n\r\nFixes #24015.\r\n\r\nFixes #24051.\r\nFixes #24037.\r\nFixes #23853.\r\nFixes #21942.\r\ncc #21756.\r\n\r\ncc @alexcrichton (this fixes crates.io)\r\nr? @aturon ","created_at":"2015-04-04T10:03:29Z","updated_at":"2015-04-06T19:01:14Z","closed_at":"2015-04-06T19:01:14Z","merged_at":"2015-04-06T19:01:14Z","merge_commit_sha":"5ed51494c657870663f82054f591ced8fa30da6b","assignee":{"login":"aturon","id":709807,"avatar_url":"https://avatars.githubusercontent.com/u/709807?v=3","gravatar_id":"","url":"https://api.github.com/users/aturon","html_url":"https://github.com/aturon","followers_url":"https://api.github.com/users/aturon/followers","following_url":"https://api.github.com/users/aturon/following{/other_user}","gists_url":"https://api.github.com/users/aturon/gists{/gist_id}","starred_url":"https://api.github.com/users/aturon/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/aturon/subscriptions","organizations_url":"https://api.github.com/users/aturon/orgs","repos_url":"https://api.github.com/users/aturon/repos","events_url":"https://api.github.com/users/aturon/events{/privacy}","received_events_url":"https://api.github.com/users/aturon/received_events","type":"User","site_admin":false},"milestone":null,"commits_url":"https://api.github.com/repos/rust-lang/rust/pulls/24056/commits","review_comments_url":"https://api.github.com/repos/rust-lang/rust/pulls/24056/comments","review_comment_url":"https://api.github.com/repos/rust-lang/rust/pulls/comments{/number}","comments_url":"https://api.github.com/repos/rust-lang/rust/issues/24056/comments","statuses_url":"https://api.github.com/repos/rust-lang/rust/statuses/0d56699d41c5683935ec4c182baa867756ae4e79","head":{"label":"nikomatsakis:issue-23853-crates-io","ref":"issue-23853-crates-io","sha":"0d56699d41c5683935ec4c182baa867756ae4e79","user":{"login":"nikomatsakis","id":155238,"avatar_url":"https://avatars.githubusercontent.com/u/155238?v=3","gravatar_id":"","url":"https://api.github.com/users/nikomatsakis","html_url":"https://github.com/nikomatsakis","followers_url":"https://api.github.com/users/nikomatsakis/followers","following_url":"https://api.github.com/users/nikomatsakis/following{/other_user}","gists_url":"https://api.github.com/users/nikomatsakis/gists{/gist_id}","starred_url":"https://api.github.com/users/nikomatsakis/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nikomatsakis/subscriptions","organizations_url":"https://api.github.com/users/nikomatsakis/orgs","repos_url":"https://api.github.com/users/nikomatsakis/repos","events_url":"https://api.github.com/users/nikomatsakis/events{/privacy}","received_events_url":"https://api.github.com/users/nikomatsakis/received_events","type":"User","site_admin":false},"repo":{"id":1672543,"name":"rust","full_name":"nikomatsakis/rust","owner":{"login":"nikomatsakis","id":155238,"avatar_url":"https://avatars.githubusercontent.com/u/155238?v=3","gravatar_id":"","url":"https://api.github.com/users/nikomatsakis","html_url":"https://github.com/nikomatsakis","followers_url":"https://api.github.com/users/nikomatsakis/followers","following_url":"https://api.github.com/users/nikomatsakis/following{/other_user}","gists_url":"https://api.github.com/users/nikomatsakis/gists{/gist_id}","starred_url":"https://api.github.com/users/nikomatsakis/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nikomatsakis/subscriptions","organizations_url":"https://api.github.com/users/nikomatsakis/orgs","repos_url":"https://api.github.com/users/nikomatsakis/repos","events_url":"https://api.github.com/users/nikomatsakis/events{/privacy}","received_events_url":"https://api.github.com/users/nikomatsakis/received_events","type":"User","site_admin":false},"private":false,"html_url":"https://github.com/nikomatsakis/rust","description":"A work-in-progress programming language; not yet suitable for users","fork":true,"url":"https://api.github.com/repos/nikomatsakis/rust","forks_url":"https://api.github.com/repos/nikomatsakis/rust/forks","keys_url":"https://api.github.com/repos/nikomatsakis/rust/keys{/key_id}","collaborators_url":"https://api.github.com/repos/nikomatsakis/rust/collaborators{/collaborator}","teams_url":"https://api.github.com/repos/nikomatsakis/rust/teams","hooks_url":"https://api.github.com/repos/nikomatsakis/rust/hooks","issue_events_url":"https://api.github.com/repos/nikomatsakis/rust/issues/events{/number}","events_url":"https://api.github.com/repos/nikomatsakis/rust/events","assignees_url":"https://api.github.com/repos/nikomatsakis/rust/assignees{/user}","branches_url":"https://api.github.com/repos/nikomatsakis/rust/branches{/branch}","tags_url":"https://api.github.com/repos/nikomatsakis/rust/tags","blobs_url":"https://api.github.com/repos/nikomatsakis/rust/git/blobs{/sha}","git_tags_url":"https://api.github.com/repos/nikomatsakis/rust/git/tags{/sha}","git_refs_url":"https://api.github.com/repos/nikomatsakis/rust/git/refs{/sha}","trees_url":"https://api.github.com/repos/nikomatsakis/rust/git/trees{/sha}","statuses_url":"https://api.github.com/repos/nikomatsakis/rust/statuses/{sha}","languages_url":"https://api.github.com/repos/nikomatsakis/rust/languages","stargazers_url":"https://api.github.com/repos/nikomatsakis/rust/stargazers","contributors_url":"https://api.github.com/repos/nikomatsakis/rust/contributors","subscribers_url":"https://api.github.com/repos/nikomatsakis/rust/subscribers","subscription_url":"https://api.github.com/repos/nikomatsakis/rust/subscription","commits_url":"https://api.github.com/repos/nikomatsakis/rust/commits{/sha}","git_commits_url":"https://api.github.com/repos/nikomatsakis/rust/git/commits{/sha}","comments_url":"https://api.github.com/repos/nikomatsakis/rust/comments{/number}","issue_comment_url":"https://api.github.com/repos/nikomatsakis/rust/issues/comments{/number}","contents_url":"https://api.github.com/repos/nikomatsakis/rust/contents/{+path}","compare_url":"https://api.github.com/repos/nikomatsakis/rust/compare/{base}...{head}","merges_url":"https://api.github.com/repos/nikomatsakis/rust/merges","archive_url":"https://api.github.com/repos/nikomatsakis/rust/{archive_format}{/ref}","downloads_url":"https://api.github.com/repos/nikomatsakis/rust/downloads","issues_url":"https://api.github.com/repos/nikomatsakis/rust/issues{/number}","pulls_url":"https://api.github.com/repos/nikomatsakis/rust/pulls{/number}","milestones_url":"https://api.github.com/repos/nikomatsakis/rust/milestones{/number}","notifications_url":"https://api.github.com/repos/nikomatsakis/rust/notifications{?since,all,participating}","labels_url":"https://api.github.com/repos/nikomatsakis/rust/labels{/name}","releases_url":"https://api.github.com/repos/nikomatsakis/rust/releases{/id}","created_at":"2011-04-27T20:20:29Z","updated_at":"2014-07-10T00:11:47Z","pushed_at":"2015-04-06T13:39:20Z","git_url":"git://github.com/nikomatsakis/rust.git","ssh_url":"git@github.com:nikomatsakis/rust.git","clone_url":"https://github.com/nikomatsakis/rust.git","svn_url":"https://github.com/nikomatsakis/rust","homepage":"","size":281899,"stargazers_count":4,"watchers_count":4,"language":"Rust","has_issues":false,"has_downloads":true,"has_wiki":true,"has_pages":false,"forks_count":0,"mirror_url":null,"open_issues_count":0,"forks":0,"open_issues":0,"watchers":4,"default_branch":"master"}},"base":{"label":"rust-lang:master","ref":"master","sha":"cf51e55274d6f2eabaf04ff2fc7a6cd61180a0ac","user":{"login":"rust-lang","id":5430905,"avatar_url":"https://avatars.githubusercontent.com/u/5430905?v=3","gravatar_id":"","url":"https://api.github.com/users/rust-lang","html_url":"https://github.com/rust-lang","followers_url":"https://api.github.com/users/rust-lang/followers","following_url":"https://api.github.com/users/rust-lang/following{/other_user}","gists_url":"https://api.github.com/users/rust-lang/gists{/gist_id}","starred_url":"https://api.github.com/users/rust-lang/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rust-lang/subscriptions","organizations_url":"https://api.github.com/users/rust-lang/orgs","repos_url":"https://api.github.com/users/rust-lang/repos","events_url":"https://api.github.com/users/rust-lang/events{/privacy}","received_events_url":"https://api.github.com/users/rust-lang/received_events","type":"Organization","site_admin":false},"repo":{"id":724712,"name":"rust","full_name":"rust-lang/rust","owner":{"login":"rust-lang","id":5430905,"avatar_url":"https://avatars.githubusercontent.com/u/5430905?v=3","gravatar_id":"","url":"https://api.github.com/users/rust-lang","html_url":"https://github.com/rust-lang","followers_url":"https://api.github.com/users/rust-lang/followers","following_url":"https://api.github.com/users/rust-lang/following{/other_user}","gists_url":"https://api.github.com/users/rust-lang/gists{/gist_id}","starred_url":"https://api.github.com/users/rust-lang/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rust-lang/subscriptions","organizations_url":"https://api.github.com/users/rust-lang/orgs","repos_url":"https://api.github.com/users/rust-lang/repos","events_url":"https://api.github.com/users/rust-lang/events{/privacy}","received_events_url":"https://api.github.com/users/rust-lang/received_events","type":"Organization","site_admin":false},"private":false,"html_url":"https://github.com/rust-lang/rust","description":"a safe, concurrent, practical language","fork":false,"url":"https://api.github.com/repos/rust-lang/rust","forks_url":"https://api.github.com/repos/rust-lang/rust/forks","keys_url":"https://api.github.com/repos/rust-lang/rust/keys{/key_id}","collaborators_url":"https://api.github.com/repos/rust-lang/rust/collaborators{/collaborator}","teams_url":"https://api.github.com/repos/rust-lang/rust/teams","hooks_url":"https://api.github.com/repos/rust-lang/rust/hooks","issue_events_url":"https://api.github.com/repos/rust-lang/rust/issues/events{/number}","events_url":"https://api.github.com/repos/rust-lang/rust/events","assignees_url":"https://api.github.com/repos/rust-lang/rust/assignees{/user}","branches_url":"https://api.github.com/repos/rust-lang/rust/branches{/branch}","tags_url":"https://api.github.com/repos/rust-lang/rust/tags","blobs_url":"https://api.github.com/repos/rust-lang/rust/git/blobs{/sha}","git_tags_url":"https://api.github.com/repos/rust-lang/rust/git/tags{/sha}","git_refs_url":"https://api.github.com/repos/rust-lang/rust/git/refs{/sha}","trees_url":"https://api.github.com/repos/rust-lang/rust/git/trees{/sha}","statuses_url":"https://api.github.com/repos/rust-lang/rust/statuses/{sha}","languages_url":"https://api.github.com/repos/rust-lang/rust/languages","stargazers_url":"https://api.github.com/repos/rust-lang/rust/stargazers","contributors_url":"https://api.github.com/repos/rust-lang/rust/contributors","subscribers_url":"https://api.github.com/repos/rust-lang/rust/subscribers","subscription_url":"https://api.github.com/repos/rust-lang/rust/subscription","commits_url":"https://api.github.com/repos/rust-lang/rust/commits{/sha}","git_commits_url":"https://api.github.com/repos/rust-lang/rust/git/commits{/sha}","comments_url":"https://api.github.com/repos/rust-lang/rust/comments{/number}","issue_comment_url":"https://api.github.com/repos/rust-lang/rust/issues/comments{/number}","contents_url":"https://api.github.com/repos/rust-lang/rust/contents/{+path}","compare_url":"https://api.github.com/repos/rust-lang/rust/compare/{base}...{head}","merges_url":"https://api.github.com/repos/rust-lang/rust/merges","archive_url":"https://api.github.com/repos/rust-lang/rust/{archive_format}{/ref}","downloads_url":"https://api.github.com/repos/rust-lang/rust/downloads","issues_url":"https://api.github.com/repos/rust-lang/rust/issues{/number}","pulls_url":"https://api.github.com/repos/rust-lang/rust/pulls{/number}","milestones_url":"https://api.github.com/repos/rust-lang/rust/milestones{/number}","notifications_url":"https://api.github.com/repos/rust-lang/rust/notifications{?since,all,participating}","labels_url":"https://api.github.com/repos/rust-lang/rust/labels{/name}","releases_url":"https://api.github.com/repos/rust-lang/rust/releases{/id}","created_at":"2010-06-16T20:39:03Z","updated_at":"2015-04-06T19:01:09Z","pushed_at":"2015-04-06T19:01:10Z","git_url":"git://github.com/rust-lang/rust.git","ssh_url":"git@github.com:rust-lang/rust.git","clone_url":"https://github.com/rust-lang/rust.git","svn_url":"https://github.com/rust-lang/rust","homepage":"http://www.rust-lang.org","size":537818,"stargazers_count":10139,"watchers_count":10139,"language":"Rust","has_issues":true,"has_downloads":true,"has_wiki":false,"has_pages":false,"forks_count":1948,"mirror_url":null,"open_issues_count":2069,"forks":1948,"open_issues":2069,"watchers":10139,"default_branch":"master"}},"_links":{"self":{"href":"https://api.github.com/repos/rust-lang/rust/pulls/24056"},"html":{"href":"https://github.com/rust-lang/rust/pull/24056"},"issue":{"href":"https://api.github.com/repos/rust-lang/rust/issues/24056"},"comments":{"href":"https://api.github.com/repos/rust-lang/rust/issues/24056/comments"},"review_comments":{"href":"https://api.github.com/repos/rust-lang/rust/pulls/24056/comments"},"review_comment":{"href":"https://api.github.com/repos/rust-lang/rust/pulls/comments{/number}"},"commits":{"href":"https://api.github.com/repos/rust-lang/rust/pulls/24056/commits"},"statuses":{"href":"https://api.github.com/repos/rust-lang/rust/statuses/0d56699d41c5683935ec4c182baa867756ae4e79"}},"merged":true,"mergeable":null,"mergeable_state":"unknown","merged_by":{"login":"bors","id":3372342,"avatar_url":"https://avatars.githubusercontent.com/u/3372342?v=3","gravatar_id":"","url":"https://api.github.com/users/bors","html_url":"https://github.com/bors","followers_url":"https://api.github.com/users/bors/followers","following_url":"https://api.github.com/users/bors/following{/other_user}","gists_url":"https://api.github.com/users/bors/gists{/gist_id}","starred_url":"https://api.github.com/users/bors/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/bors/subscriptions","organizations_url":"https://api.github.com/users/bors/orgs","repos_url":"https://api.github.com/users/bors/repos","events_url":"https://api.github.com/users/bors/events{/privacy}","received_events_url":"https://api.github.com/users/bors/received_events","type":"User","site_admin":false},"comments":6,"review_comments":0,"commits":1,"additions":112,"deletions":5,"changed_files":5}}