message: format warnings
diff: @@ -85,7 +85,7 @@ unsafe impl glium::backend::Backend for DummyBackend {
  "glGenBuffers" | "glGenTextures" | "glGenFramebuffers" | "glGenRenderbuffers" |
  "glGenVertexArrays" | "glGenSamplers" => {
  extern "system" fn gen(num: usize, bufs: *mut u32) {
  - for i in (0 .. num) { unsafe { *bufs.offset(i as isize) = 1; } }
  + for i in 0 .. num { unsafe { *bufs.offset(i as isize) = 1; } }
  }
  gen as *const _
  },
  @@ -115,7 +115,7 @@ unsafe impl glium::backend::Backend for DummyBackend {
  },
  "glGetFramebufferAttachmentParameteriv" => {
  - extern "system" fn get_fbap(target: u32, atch: u32, pname: u32, params: *mut i32) {
  + extern "system" fn get_fbap(_target: u32, _atch: u32, _pname: u32, _params: *mut i32) {
  }
  get_fbap as *const _
  },
  @@ -177,7 +177,7 @@ unsafe impl glium::backend::Backend for DummyBackend {
  use_program as *const _
  },
  - name => ptr::null()
  + _name => ptr::null()
  }
  }
  