dawn-cmake/test/shader_io/fragment_output_builtins_struct.wgsl

struct FragmentOutputs {
  [[builtin(frag_depth)]] frag_depth : f32;
  [[builtin(sample_mask)]] sample_mask : u32;
};

[[stage(fragment)]]
fn main() -> FragmentOutputs {
  return FragmentOutputs(1.0, 1u);
}