{"action":"closed","issue":{"url":"https://api.github.com/repos/JuliaLang/julia/issues/10647","labels_url":"https://api.github.com/repos/JuliaLang/julia/issues/10647/labels{/name}","comments_url":"https://api.github.com/repos/JuliaLang/julia/issues/10647/comments","events_url":"https://api.github.com/repos/JuliaLang/julia/issues/10647/events","html_url":"https://github.com/JuliaLang/julia/issues/10647","id":64754588,"number":10647,"title":"Self-referential Dict hangs Julia on display","user":{"login":"mauro3","id":4098145,"avatar_url":"https://avatars.githubusercontent.com/u/4098145?v=3","gravatar_id":"","url":"https://api.github.com/users/mauro3","html_url":"https://github.com/mauro3","followers_url":"https://api.github.com/users/mauro3/followers","following_url":"https://api.github.com/users/mauro3/following{/other_user}","gists_url":"https://api.github.com/users/mauro3/gists{/gist_id}","starred_url":"https://api.github.com/users/mauro3/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/mauro3/subscriptions","organizations_url":"https://api.github.com/users/mauro3/orgs","repos_url":"https://api.github.com/users/mauro3/repos","events_url":"https://api.github.com/users/mauro3/events{/privacy}","received_events_url":"https://api.github.com/users/mauro3/received_events","type":"User","site_admin":false},"labels":[],"state":"closed","locked":false,"assignee":{"login":"mbauman","id":154641,"avatar_url":"https://avatars.githubusercontent.com/u/154641?v=3","gravatar_id":"","url":"https://api.github.com/users/mbauman","html_url":"https://github.com/mbauman","followers_url":"https://api.github.com/users/mbauman/followers","following_url":"https://api.github.com/users/mbauman/following{/other_user}","gists_url":"https://api.github.com/users/mbauman/gists{/gist_id}","starred_url":"https://api.github.com/users/mbauman/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/mbauman/subscriptions","organizations_url":"https://api.github.com/users/mbauman/orgs","repos_url":"https://api.github.com/users/mbauman/repos","events_url":"https://api.github.com/users/mbauman/events{/privacy}","received_events_url":"https://api.github.com/users/mbauman/received_events","type":"User","site_admin":false},"milestone":null,"comments":8,"created_at":"2015-03-27T12:35:34Z","updated_at":"2015-05-06T14:58:17Z","closed_at":"2015-05-06T14:58:17Z","body":"```\r\n   _       _ _(_)_     |  A fresh approach to technical computing\r\n  (_)     | (_) (_)    |  Documentation: http://docs.julialang.org\r\n   _ _   _| |_  __ _   |  Type \"help()\" for help.\r\n  | | | | | | |/ _` |  |\r\n  | | |_| | | | (_| |  |  Version 0.4.0-dev+4022 (2015-03-26 19:08 UTC)\r\n _/ |\\__'_|_|_|\\__'_|  |  Commit 01a3216* (0 days old master)\r\n|__/                   |  x86_64-unknown-linux-gnu\r\n\r\njulia> oid = ObjectIdDict()\r\nObjectIdDict with 0 entries\r\n\r\njulia> oid[oid] = 5\r\n5\r\n\r\njulia> oid\r\nObjectIdDict with 1 entry:Error showing value of type ObjectIdDict:\r\n```\r\nand just hangs, Ctrl-c has no effect.  In fact it leaves the julia process in a uninterruptible sleep state, i.e. I cannot even kill it:\r\n```\r\n  PID USER      PR  NI    VIRT    RES  %CPU %MEM     TIME+ S COMMAND                          \r\n12875 mauro     20   0 8654.7m 243.2m   0.0  1.5   0:16.66 D julia0.4-pre                     \r\n  593 mauro     20   0  358.1m 119.8m   0.0  0.8   0:02.05 D julia                            \r\n```\r\n(on Arch Linux)\r\n\r\nSame for 0.3.6 and 0.2. Same for straight `Dict`.  Stumbled upon this when trying to see `Base.META`\r\n\r\nOf course there is little sense in using a self-referential Dict.  But Julia should crash more gracefully.  Self-referential ObjectIdDicts should work though.\r\n\r\nRelated:\r\n#3066 (test case in that issue works)\r\n#7217, which now also causes an uninterruptible sleep state, and not a stack-overflow like back then."}}