// Don't allow unstable features in stable functions without `allow_internal_unstable`. #![stable(feature = "rust1", since = "1.0.0")] #![feature(staged_api)] #![feature(const_fn_floating_point_arithmetic)] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "rust1", since = "1.0.0")] pub const fn foo() -> f32 { 1.0 + 1.0 //~ ERROR const-stable function cannot use `#[feature(const_fn_floating_point_arithmetic)]` } fn main() {}