{"action":"created","issue":{"url":"https://api.github.com/repos/manastech/crystal/issues/1964","labels_url":"https://api.github.com/repos/manastech/crystal/issues/1964/labels{/name}","comments_url":"https://api.github.com/repos/manastech/crystal/issues/1964/comments","events_url":"https://api.github.com/repos/manastech/crystal/issues/1964/events","html_url":"https://github.com/manastech/crystal/issues/1964","id":123578806,"number":1964,"title":"(Still) cannot compile Crystal","user":{"login":"stugol","id":1113153,"avatar_url":"https://avatars.githubusercontent.com/u/1113153?v=3","gravatar_id":"","url":"https://api.github.com/users/stugol","html_url":"https://github.com/stugol","followers_url":"https://api.github.com/users/stugol/followers","following_url":"https://api.github.com/users/stugol/following{/other_user}","gists_url":"https://api.github.com/users/stugol/gists{/gist_id}","starred_url":"https://api.github.com/users/stugol/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/stugol/subscriptions","organizations_url":"https://api.github.com/users/stugol/orgs","repos_url":"https://api.github.com/users/stugol/repos","events_url":"https://api.github.com/users/stugol/events{/privacy}","received_events_url":"https://api.github.com/users/stugol/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":51,"created_at":"2015-12-23T00:02:34Z","updated_at":"2015-12-27T00:38:23Z","closed_at":null,"body":"After an absence, I came back to Crystal and tried to run a script. As far as I know, nothing had changed. Nevertheless, I received the following errors:\r\n```\r\nUsing compiled compiler at .build/crystal\r\n/opt/t/crystal/.crystal/mnt/data/Documents/Programming/crystal/delta-backup-tests.cr/main.o: In function `__crystal_main':\r\nmain_module:(.text+0x5604): undefined reference to `GC_get_push_other_roots'\r\nmain_module:(.text+0x566a): undefined reference to `GC_set_push_other_roots'\r\nmain_module:(.text+0x566f): undefined reference to `co_thread_init'\r\n/opt/t/crystal/.crystal/mnt/data/Documents/Programming/crystal/delta-backup-tests.cr/Fiber.o: In function `*Fiber#initialize<Fiber>:Fiber':\r\nFiber:(.text+0x193): undefined reference to `co_set_data'\r\n/opt/t/crystal/.crystal/mnt/data/Documents/Programming/crystal/delta-backup-tests.cr/Fiber.o: In function `*Fiber#initialize<Fiber, &( -> Void)>:Fiber':\r\nFiber:(.text+0x333): undefined reference to `co_set_data'\r\n/opt/t/crystal/.crystal/mnt/data/Documents/Programming/crystal/delta-backup-tests.cr/Fiber.o: In function `*Fiber::current:Fiber':\r\nFiber:(.text+0x62d): undefined reference to `co_get_data'\r\ncollect2: error: ld returned 1 exit status\r\n```\r\nSo I figured my installation of Crystal was broken, and tried to download and compile a fresh one:\r\n```\r\n> git clone https://github.com/manastech/crystal.git\r\n> cd crystal\r\n> make\r\nCRYSTAL_CONFIG_PATH=`pwd`/src ./bin/crystal build  -o .build/crystal src/compiler/crystal.cr\r\nUsing compiled compiler at .build/crystal\r\nError in ./src/compiler/crystal/tools/context.cr:32: undefined method 'mapping' for JSON:Class\r\n\r\n    JSON.mapping({\r\n         ^~~~~~~\r\n\r\n\r\nMakefile:31: recipe for target '.build/crystal' failed\r\nmake: *** [.build/crystal] Error 1\r\n```\r\nSo I'm kinda at a loss here. Should I reinstall the Debian repo version, and use that to compile the latest version? Would that even work?\r\n\r\nMy current version of Crystal is apparently:\r\n```\r\n> crystal -v\r\nUsing compiled compiler at .build/crystal\r\nCrystal 0.7.6 [60e7974] (Thu 20 Aug 00:29:07 UTC 2015)\r\n```\r\n...help please?"},"comment":{"url":"https://api.github.com/repos/manastech/crystal/issues/comments/167373430","html_url":"https://github.com/manastech/crystal/issues/1964#issuecomment-167373430","issue_url":"https://api.github.com/repos/manastech/crystal/issues/1964","id":167373430,"user":{"login":"waterlink","id":609046,"avatar_url":"https://avatars.githubusercontent.com/u/609046?v=3","gravatar_id":"","url":"https://api.github.com/users/waterlink","html_url":"https://github.com/waterlink","followers_url":"https://api.github.com/users/waterlink/followers","following_url":"https://api.github.com/users/waterlink/following{/other_user}","gists_url":"https://api.github.com/users/waterlink/gists{/gist_id}","starred_url":"https://api.github.com/users/waterlink/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/waterlink/subscriptions","organizations_url":"https://api.github.com/users/waterlink/orgs","repos_url":"https://api.github.com/users/waterlink/repos","events_url":"https://api.github.com/users/waterlink/events{/privacy}","received_events_url":"https://api.github.com/users/waterlink/received_events","type":"User","site_admin":false},"created_at":"2015-12-27T00:38:23Z","updated_at":"2015-12-27T00:38:23Z","body":"The difference of docker from conventional virtualization tools, is that most of the time you don't run a whole OS inside (though you can), rather you run only one program (for example `crystal spec`) and it will be the only process inside (with PID=1)."}}