test/shader_io/fragment_input_locations.wgsl

@stage(fragment)
fn main(
  @location(0) @interpolate(flat) loc0 : i32,
  @location(1) @interpolate(flat) loc1 : u32,
  @location(2) loc2 : f32,
  @location(3) loc3 : vec4<f32>,
) {
  let i : i32 = loc0;
  let u : u32 = loc1;
  let f : f32 = loc2;
  let v : vec4<f32> = loc3;
}