{"action":"created","issue":{"url":"https://api.github.com/repos/JuliaLang/julia/issues/9147","labels_url":"https://api.github.com/repos/JuliaLang/julia/issues/9147/labels{/name}","comments_url":"https://api.github.com/repos/JuliaLang/julia/issues/9147/comments","events_url":"https://api.github.com/repos/JuliaLang/julia/issues/9147/events","html_url":"https://github.com/JuliaLang/julia/issues/9147","id":50041971,"number":9147,"title":"zero out memory of uninitialized fields","user":{"login":"StefanKarpinski","id":153596,"avatar_url":"https://avatars.githubusercontent.com/u/153596?v=3","gravatar_id":"","url":"https://api.github.com/users/StefanKarpinski","html_url":"https://github.com/StefanKarpinski","followers_url":"https://api.github.com/users/StefanKarpinski/followers","following_url":"https://api.github.com/users/StefanKarpinski/following{/other_user}","gists_url":"https://api.github.com/users/StefanKarpinski/gists{/gist_id}","starred_url":"https://api.github.com/users/StefanKarpinski/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/StefanKarpinski/subscriptions","organizations_url":"https://api.github.com/users/StefanKarpinski/orgs","repos_url":"https://api.github.com/users/StefanKarpinski/repos","events_url":"https://api.github.com/users/StefanKarpinski/events{/privacy}","received_events_url":"https://api.github.com/users/StefanKarpinski/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/JuliaLang/julia/milestones/11","html_url":"https://github.com/JuliaLang/julia/milestones/0.4.0","labels_url":"https://api.github.com/repos/JuliaLang/julia/milestones/11/labels","id":748886,"number":11,"title":"0.4.0","description":"For tracking release-defining items for 0.4: important new features, breaking changes, and blocking bugs.\r\n\r\nAfter a brief period for deciding scope, adding issues to this milestone is not allowed. Once the items in this milestone are done, 0.4 will enter its stabilizing period and a release candidate can be made soon after.","creator":{"login":"JeffBezanson","id":744556,"avatar_url":"https://avatars.githubusercontent.com/u/744556?v=3","gravatar_id":"","url":"https://api.github.com/users/JeffBezanson","html_url":"https://github.com/JeffBezanson","followers_url":"https://api.github.com/users/JeffBezanson/followers","following_url":"https://api.github.com/users/JeffBezanson/following{/other_user}","gists_url":"https://api.github.com/users/JeffBezanson/gists{/gist_id}","starred_url":"https://api.github.com/users/JeffBezanson/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/JeffBezanson/subscriptions","organizations_url":"https://api.github.com/users/JeffBezanson/orgs","repos_url":"https://api.github.com/users/JeffBezanson/repos","events_url":"https://api.github.com/users/JeffBezanson/events{/privacy}","received_events_url":"https://api.github.com/users/JeffBezanson/received_events","type":"User","site_admin":false},"open_issues":20,"closed_issues":45,"state":"open","created_at":"2014-08-10T18:13:46Z","updated_at":"2015-06-02T16:48:40Z","due_on":"2015-06-20T18:30:00Z","closed_at":null},"comments":63,"created_at":"2014-11-25T15:34:28Z","updated_at":"2015-06-02T19:32:02Z","closed_at":null,"body":"Raised here: https://groups.google.com/forum/#!topic/julia-users/O5S8pPav5Ks."},"comment":{"url":"https://api.github.com/repos/JuliaLang/julia/issues/comments/108068117","html_url":"https://github.com/JuliaLang/julia/issues/9147#issuecomment-108068117","issue_url":"https://api.github.com/repos/JuliaLang/julia/issues/9147","id":108068117,"user":{"login":"carnaval","id":5307791,"avatar_url":"https://avatars.githubusercontent.com/u/5307791?v=3","gravatar_id":"","url":"https://api.github.com/users/carnaval","html_url":"https://github.com/carnaval","followers_url":"https://api.github.com/users/carnaval/followers","following_url":"https://api.github.com/users/carnaval/following{/other_user}","gists_url":"https://api.github.com/users/carnaval/gists{/gist_id}","starred_url":"https://api.github.com/users/carnaval/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/carnaval/subscriptions","organizations_url":"https://api.github.com/users/carnaval/orgs","repos_url":"https://api.github.com/users/carnaval/repos","events_url":"https://api.github.com/users/carnaval/events{/privacy}","received_events_url":"https://api.github.com/users/carnaval/received_events","type":"User","site_admin":false},"created_at":"2015-06-02T19:32:02Z","updated_at":"2015-06-02T19:32:02Z","body":"I think performance is not the problem here. Even if we initialize all memory my point is that it should always be explicit. i.e., remove the Array constructor for bits types and only allow zeros(), ones(), fill() ...\r\n\r\nAgain, the zero bit pattern has no meaning for non-numeric types. The fact that it often does is only more of a pitfall, not less. I'm not arguing for performance, I'm arguing _for_ actively undefined behavior, coupled with good tools to catch it."}}