rust/tests/ui/consts/const-extern-fn/const-extern-fn-min-const-fn.rs

const extern "C" fn ptr_cast(val: *const u8) {
    val as usize;
    //~^ ERROR pointers cannot be cast to integers
}

fn main() {}
stabilize `const_extern_fn` 2024-08-29 15:33:34 +02:00			`const extern "C" fn ptr_cast(val: *const u8) {`
			`val as usize;`
			`//~^ ERROR pointers cannot be cast to integers`
			`}`
Add support for 'extern const fn' This works just as you might expect - an 'extern const fn' is a 'const fn' that is callable from foreign code. Currently, panicking is not allowed in consts. When RFC 2345 is stabilized, then panicking in an 'extern const fn' will produce a compile-time error when invoked at compile time, and an abort when invoked at runtime. Since this is extending the language (we're allowing the `const` keyword in a new context), I believe that this will need an FCP. However, it's a very minor change, so I didn't think that filing an RFC was necessary. This will allow libc (and other FFI crates) to make many functions `const`, without having to give up on making them `extern` as well. 2019-09-29 19:22:18 -04:00
			`fn main() {}`