{"action":"opened","issue":{"url":"https://api.github.com/repos/antoinealb/rust-demo-cortex-m4/issues/4","labels_url":"https://api.github.com/repos/antoinealb/rust-demo-cortex-m4/issues/4/labels{/name}","comments_url":"https://api.github.com/repos/antoinealb/rust-demo-cortex-m4/issues/4/comments","events_url":"https://api.github.com/repos/antoinealb/rust-demo-cortex-m4/issues/4/events","html_url":"https://github.com/antoinealb/rust-demo-cortex-m4/issues/4","id":104462978,"number":4,"title":"hard float: wrong argument type","user":{"login":"nuft","id":7102039,"avatar_url":"https://avatars.githubusercontent.com/u/7102039?v=3","gravatar_id":"","url":"https://api.github.com/users/nuft","html_url":"https://github.com/nuft","followers_url":"https://api.github.com/users/nuft/followers","following_url":"https://api.github.com/users/nuft/following{/other_user}","gists_url":"https://api.github.com/users/nuft/gists{/gist_id}","starred_url":"https://api.github.com/users/nuft/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nuft/subscriptions","organizations_url":"https://api.github.com/users/nuft/orgs","repos_url":"https://api.github.com/users/nuft/repos","events_url":"https://api.github.com/users/nuft/events{/privacy}","received_events_url":"https://api.github.com/users/nuft/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2015-09-02T11:48:22Z","updated_at":"2015-09-02T11:48:22Z","closed_at":null,"body":"In [LM4F_startup.c](https://github.com/antoinealb/rust-demo-cortex-m4/blob/feature-hardfloat-abi/LM4F_startup.c#L279) you should add a C declaration for the function rust_float_test to tell the C compiler what argument type is expected. (something like `float rust_float_test(float);`)\r\n\r\nThis prevents GCC from assuming double as the default argument type, leading to the following incorrect function call:\r\n```\r\nvldr        d0, [pc, #28]    ; 300 <rst_handler+0x68>\r\nbl          34c <rust_float_test>\r\n```\r\n"}}