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#![deny(unconditional_recursion)]
#![allow(dead_code)]
fn foo() { //~ ERROR function cannot return without recursing
foo();
}
fn bar() {
if true {
bar()
}
}
fn baz() { //~ ERROR function cannot return without recursing
if true {
baz()
} else {
baz()
}
}
fn qux() {
loop {}
}
fn quz() -> bool { //~ ERROR function cannot return without recursing
if true {
while quz() {}
true
} else {
loop { quz(); }
}
}
// Trait method calls.
trait Foo {
fn bar(&self) { //~ ERROR function cannot return without recursing
self.bar()
}
}
impl Foo for Box<dyn Foo + 'static> {
fn bar(&self) { //~ ERROR function cannot return without recursing
loop {
self.bar()
}
}
}
// Trait method call with integer fallback after method resolution.
impl Foo for i32 {
fn bar(&self) { //~ ERROR function cannot return without recursing
0.bar()
}
}
impl Foo for u32 {
fn bar(&self) {
0.bar()
}
}
// Trait method calls via paths.
trait Foo2 {
fn bar(&self) { //~ ERROR function cannot return without recursing
Foo2::bar(self)
}
}
impl Foo2 for Box<dyn Foo2 + 'static> {
fn bar(&self) { //~ ERROR function cannot return without recursing
loop {
Foo2::bar(self)
}
}
}
struct Baz;
impl Baz {
// Inherent method call.
fn qux(&self) { //~ ERROR function cannot return without recursing
self.qux();
}
// Inherent method call via path.
fn as_ref(&self) -> &Self { //~ ERROR function cannot return without recursing
Baz::as_ref(self)
}
}
// Trait method calls to impls via paths.
impl Default for Baz {
fn default() -> Baz { //~ ERROR function cannot return without recursing
let x = Default::default();
x
}
}
// Overloaded operators.
impl std::ops::Deref for Baz {
type Target = ();
fn deref(&self) -> &() { //~ ERROR function cannot return without recursing
&**self
}
}
impl std::ops::Index<usize> for Baz {
type Output = Baz;
fn index(&self, x: usize) -> &Baz { //~ ERROR function cannot return without recursing
&self[x]
}
}
// Overloaded autoderef.
struct Quux;
impl std::ops::Deref for Quux {
type Target = Baz;
fn deref(&self) -> &Baz { //~ ERROR function cannot return without recursing
self.as_ref()
}
}
fn all_fine() {
let _f = all_fine;
}
// issue 26333
trait Bar {
fn method<T: Bar>(&self, x: &T) {
x.method(x)
}
}
// Do not trigger on functions that may diverge instead of self-recursing (#54444)
pub fn loops(x: bool) {
if x {
loops(x);
} else {
loop {}
}
}
pub fn panics(x: bool) {
if x {
panics(!x);
} else {
panic!("panics");
}
}
pub fn unreachable1() {
panic!();
unreachable1(); // WARN unreachable statement
}
pub fn unreachable2() {
loop {}
unreachable2(); // WARN unreachable statement
}
pub fn drop_and_replace(mut a: Option<String>) { //~ ERROR function cannot return without recursing
a = None;
drop_and_replace(a);
}
// Calls are assumed to return normally.
pub fn call() -> String { //~ ERROR function cannot return without recursing
let s = String::new();
call();
s
}
// Arithmetic operations are assumed not to overflow.
pub fn overflow_check(a: i32, b: i32) { //~ ERROR function cannot return without recursing
let _ = a + b;
overflow_check(a, b);
}
pub struct Point {
pub x: f32,
pub y: f32,
}
impl Default for Point {
fn default() -> Self { //~ ERROR function cannot return without recursing
Point {
x: Default::default(),
..Default::default()
}
}
}
fn main() {}
|
