// Don't allow unstable features in stable functions without `allow_internal_unstable`. #![stable(feature = "rust1", since = "1.0.0")] #![feature(staged_api)] #![feature(const_transmute, const_fn)] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "rust1", since = "1.0.0")] pub const fn foo() -> i32 { unsafe { std::mem::transmute(4u32) } //~ ERROR can only call `transmute` from const items } fn main() {}