#![feature(platform_intrinsics, repr_simd)] extern "platform-intrinsic" { fn simd_select(m: M, yes: T, no: T) -> T; } #[repr(simd)] #[allow(non_camel_case_types)] #[derive(Copy, Clone)] struct i32x2(i32, i32); fn main() { unsafe { let x = i32x2(0, 1); simd_select(x, x, x); //~ERROR: must be all-0-bits or all-1-bits } }