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|
#![allow(dead_code, path_statements)]
#![deny(unused_attributes, unused_must_use)]
#![feature(asm_experimental_arch, stmt_expr_attributes, trait_alias)]
#[must_use] //~ ERROR `#[must_use]` has no effect
extern crate std as std2;
#[must_use] //~ ERROR `#[must_use]` has no effect
mod test_mod {}
#[must_use] //~ ERROR `#[must_use]` has no effect
use std::arch::global_asm;
#[must_use] //~ ERROR `#[must_use]` has no effect
const CONST: usize = 4;
#[must_use] //~ ERROR `#[must_use]` has no effect
#[no_mangle]
static STATIC: usize = 4;
#[must_use]
struct X;
#[must_use]
enum Y {
Z,
}
#[must_use]
union U {
unit: (),
}
#[must_use] //~ ERROR `#[must_use]` has no effect
impl U {
#[must_use]
fn method() -> i32 {
4
}
}
#[must_use]
#[no_mangle]
fn foo() -> i64 {
4
}
#[must_use] //~ ERROR `#[must_use]` has no effect
extern "Rust" {
#[link_name = "STATIC"]
#[must_use] //~ ERROR `#[must_use]` has no effect
static FOREIGN_STATIC: usize;
#[link_name = "foo"]
#[must_use]
fn foreign_foo() -> i64;
}
#[must_use] //~ ERROR unused attribute
global_asm!("");
#[must_use] //~ ERROR `#[must_use]` has no effect
type UseMe = ();
fn qux<#[must_use] T>(_: T) {} //~ ERROR `#[must_use]` has no effect
#[must_use]
trait Use {
#[must_use] //~ ERROR `#[must_use]` has no effect
const ASSOC_CONST: usize = 4;
#[must_use] //~ ERROR `#[must_use]` has no effect
type AssocTy;
#[must_use]
fn get_four(&self) -> usize {
4
}
}
#[must_use] //~ ERROR `#[must_use]` has no effect
impl Use for () {
type AssocTy = ();
#[must_use] //~ ERROR `#[must_use]` has no effect
fn get_four(&self) -> usize {
4
}
}
#[must_use] //~ ERROR `#[must_use]` has no effect
trait Alias = Use;
#[must_use] //~ ERROR `#[must_use]` has no effect
macro_rules! cool_macro {
() => {
4
};
}
fn main() {
#[must_use] //~ ERROR `#[must_use]` has no effect
let x = || {};
x();
let x = #[must_use] //~ ERROR `#[must_use]` has no effect
|| {};
x();
X; //~ ERROR that must be used
Y::Z; //~ ERROR that must be used
U { unit: () }; //~ ERROR that must be used
U::method(); //~ ERROR that must be used
foo(); //~ ERROR that must be used
unsafe {
foreign_foo(); //~ ERROR that must be used
};
CONST;
STATIC;
unsafe { FOREIGN_STATIC };
cool_macro!();
qux(4);
().get_four(); //~ ERROR that must be used
match Some(4) {
#[must_use] //~ ERROR `#[must_use]` has no effect
Some(res) => res,
None => 0,
};
struct PatternField {
foo: i32,
}
let s = PatternField { #[must_use] foo: 123 }; //~ ERROR `#[must_use]` has no effect
let PatternField { #[must_use] foo } = s; //~ ERROR `#[must_use]` has no effect
}
|
