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// revisions: no_drop_tracking drop_tracking drop_tracking_mir
// [drop_tracking] compile-flags: -Zdrop-tracking
// [drop_tracking_mir] compile-flags: -Zdrop-tracking-mir
#![feature(generators)]
#![feature(auto_traits)]
#![feature(negative_impls)]
auto trait Foo {}
struct No;
impl !Foo for No {}
struct A<'a, 'b>(&'a mut bool, &'b mut bool, No);
impl<'a, 'b: 'a> Foo for A<'a, 'b> {}
struct OnlyFooIfStaticRef(No);
impl Foo for &'static OnlyFooIfStaticRef {}
struct OnlyFooIfRef(No);
impl<'a> Foo for &'a OnlyFooIfRef {}
fn assert_foo<T: Foo>(f: T) {}
fn main() {
// Make sure 'static is erased for generator interiors so we can't match it in trait selection
let x: &'static _ = &OnlyFooIfStaticRef(No);
let gen = || {
let x = x;
yield;
assert_foo(x);
};
assert_foo(gen);
//~^ ERROR implementation of `Foo` is not general enough
// Allow impls which matches any lifetime
let x = &OnlyFooIfRef(No);
let gen = || {
let x = x;
yield;
assert_foo(x);
};
assert_foo(gen); // ok
// Disallow impls which relates lifetimes in the generator interior
let gen = || {
let a = A(&mut true, &mut true, No);
//~^ temporary value dropped while borrowed
//~| temporary value dropped while borrowed
yield;
assert_foo(a);
};
assert_foo(gen);
//~^ ERROR not general enough
}
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