#![allow(incomplete_features)] #![feature(explicit_tail_calls)] const fn f() { if false { become not_const(); //~^ error: cannot call non-const fn `not_const` in constant functions } } const fn g((): ()) { if false { become yes_const(not_const()); //~^ error: cannot call non-const fn `not_const` in constant functions } } fn not_const() {} const fn yes_const((): ()) {} fn main() {}