diff --git a/tests/ui/async-await/pin-reborrow-arg.rs b/tests/ui/async-await/pin-reborrow-arg.rs index 34f23533b65..b3e8718d036 100644 --- a/tests/ui/async-await/pin-reborrow-arg.rs +++ b/tests/ui/async-await/pin-reborrow-arg.rs @@ -15,7 +15,7 @@ fn baz(self: Pin<&mut Self>) { fn foo(_: Pin<&mut Foo>) { } -fn bar(mut x: Pin<&mut Foo>) { +fn bar(x: Pin<&mut Foo>) { foo(x); foo(x); // for this to work we need to automatically reborrow, // as if the user had written `foo(x.as_mut())`. diff --git a/tests/ui/async-await/pin-reborrow-once.rs b/tests/ui/async-await/pin-reborrow-once.rs new file mode 100644 index 00000000000..241efadef7d --- /dev/null +++ b/tests/ui/async-await/pin-reborrow-once.rs @@ -0,0 +1,13 @@ +#![feature(pin_ergonomics)] +#![allow(dead_code, incomplete_features)] + +// Make sure with pin reborrowing that we can only get one mutable reborrow of a pinned reference. + +use std::pin::{pin, Pin}; + +fn twice(_: Pin<&mut i32>, _: Pin<&mut i32>) {} + +fn main() { + let x = pin!(42); + twice(x, x); //~ ERROR cannot borrow +} diff --git a/tests/ui/async-await/pin-reborrow-once.stderr b/tests/ui/async-await/pin-reborrow-once.stderr new file mode 100644 index 00000000000..b8fde8ffee8 --- /dev/null +++ b/tests/ui/async-await/pin-reborrow-once.stderr @@ -0,0 +1,12 @@ +error[E0499]: cannot borrow `*x.__pointer` as mutable more than once at a time + --> $DIR/pin-reborrow-once.rs:12:14 + | +LL | twice(x, x); + | ----- - ^ second mutable borrow occurs here + | | | + | | first mutable borrow occurs here + | first borrow later used by call + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0499`.