Add more tests

3 files changed, 30 insertions, 1 deletions

diff --git a/tests/ui/traits/dyn-drop-principal.rs b/tests/ui/traits/dyn-drop-principal.rs
index eeff0550fcb..c233127e43d 100644
--- a/tests/ui/traits/dyn-drop-principal.rs
+++ b/tests/ui/traits/dyn-drop-principal.rs
@@ -1,7 +1,7 @@
 //@ run-pass
 //@ check-run-results
 
-use std::any::Any;
+use std::{alloc::Layout, any::Any};
 
 const fn yeet_principal(x: Box<dyn Any + Send>) -> Box<dyn Send> {
     x
@@ -35,12 +35,18 @@ fn goodbye() {
 
 fn main() {
     let x = Box::new(CallMe::new(goodbye)) as Box<dyn Any + Send>;
+    let x_layout = Layout::for_value(&*x);
     let y = yeet_principal(x);
+    let y_layout = Layout::for_value(&*y);
+    assert_eq!(x_layout, y_layout);
     println!("before");
     drop(y);
 
     let x = Box::new(CallMe::new(goodbye)) as Box<dyn Bar>;
+    let x_layout = Layout::for_value(&*x);
     let y = yeet_principal_2(x);
+    let y_layout = Layout::for_value(&*y);
+    assert_eq!(x_layout, y_layout);
     println!("before");
     drop(y);
 }
diff --git a/tests/ui/traits/dyn-star-drop-principal.rs b/tests/ui/traits/dyn-star-drop-principal.rs
new file mode 100644
index 00000000000..1ad99070339
--- /dev/null
+++ b/tests/ui/traits/dyn-star-drop-principal.rs
@@ -0,0 +1,12 @@
+#![feature(dyn_star)]
+#![allow(incomplete_features)]
+
+trait Trait {}
+impl Trait for usize {}
+
+fn main() {
+    // We allow &dyn Trait + Send -> &dyn Send (i.e. dropping principal),
+    // but we don't (currently?) allow the same for dyn*
+    let x: dyn* Trait + Send = 1usize;
+    x as dyn* Send; //~ error: `dyn* Trait + Send` needs to have the same ABI as a pointer
+}
diff --git a/tests/ui/traits/dyn-star-drop-principal.stderr b/tests/ui/traits/dyn-star-drop-principal.stderr
new file mode 100644
index 00000000000..721ae7e191e
--- /dev/null
+++ b/tests/ui/traits/dyn-star-drop-principal.stderr
@@ -0,0 +1,11 @@
+error[E0277]: `dyn* Trait + Send` needs to have the same ABI as a pointer
+  --> $DIR/dyn-star-drop-principal.rs:11:5
+   |
+LL |     x as dyn* Send;
+   |     ^ `dyn* Trait + Send` needs to be a pointer-like type
+   |
+   = help: the trait `PointerLike` is not implemented for `dyn* Trait + Send`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0277`.