error[E0658]: floating point arithmetic is not allowed in constant functions --> $DIR/const-extern-fn-min-const-fn.rs:5:42 | LL | const unsafe extern "C" fn use_float() { 1.0 + 1.0; } | ^^^^^^^^^ | = note: see issue #57241 for more information = help: add `#![feature(const_fn_floating_point_arithmetic)]` to the crate attributes to enable error: pointers cannot be cast to integers during const eval --> $DIR/const-extern-fn-min-const-fn.rs:7:48 | LL | const extern "C" fn ptr_cast(val: *const u8) { val as usize; } | ^^^^^^^^^^^^ | = note: at compile-time, pointers do not have an integer value = note: avoiding this restriction via `transmute`, `union`, or raw pointers leads to compile-time undefined behavior error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0658`.