#![feature(transmutability)] #![feature(generic_const_exprs)] //~^ WARN the feature `generic_const_exprs` is incomplete use std::mem::{Assume, TransmuteFrom}; pub fn is_transmutable() where (): TransmuteFrom<(), { Assume::SAFETY }>, { } fn foo() { is_transmutable::<{}>(); //~^ ERROR the trait bound `(): TransmuteFrom<(), { Assume::SAFETY }>` is not satisfied //~| ERROR mismatched types } fn main() {}