Disable dyn* upcasting

4 files changed, 57 insertions, 2 deletions

diff --git a/src/test/ui/dyn-star/no-unsize-coerce-dyn-trait.rs b/src/test/ui/dyn-star/no-unsize-coerce-dyn-trait.rs
new file mode 100644
index 00000000000..a4eb669e321
--- /dev/null
+++ b/src/test/ui/dyn-star/no-unsize-coerce-dyn-trait.rs
@@ -0,0 +1,13 @@
+#![feature(dyn_star, trait_upcasting)]
+//~^ WARN the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
+
+trait A: B {}
+trait B {}
+impl A for usize {}
+impl B for usize {}
+
+fn main() {
+    let x: Box<dyn* A> = Box::new(1usize as dyn* A);
+    let y: Box<dyn* B> = x;
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/dyn-star/no-unsize-coerce-dyn-trait.stderr b/src/test/ui/dyn-star/no-unsize-coerce-dyn-trait.stderr
new file mode 100644
index 00000000000..2fc751b3b4a
--- /dev/null
+++ b/src/test/ui/dyn-star/no-unsize-coerce-dyn-trait.stderr
@@ -0,0 +1,23 @@
+warning: the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/no-unsize-coerce-dyn-trait.rs:1:12
+   |
+LL | #![feature(dyn_star, trait_upcasting)]
+   |            ^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error[E0308]: mismatched types
+  --> $DIR/no-unsize-coerce-dyn-trait.rs:11:26
+   |
+LL |     let y: Box<dyn* B> = x;
+   |            -----------   ^ expected trait `B`, found trait `A`
+   |            |
+   |            expected due to this
+   |
+   = note: expected struct `Box<dyn* B>`
+              found struct `Box<dyn* A>`
+
+error: aborting due to previous error; 1 warning emitted
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/dyn-star/upcast.rs b/src/test/ui/dyn-star/upcast.rs
index cee76ada7df..24c077047e9 100644
--- a/src/test/ui/dyn-star/upcast.rs
+++ b/src/test/ui/dyn-star/upcast.rs
@@ -1,7 +1,6 @@
-// run-pass
+// known-bug: unknown
 
 #![feature(dyn_star, trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo: Bar {
     fn hello(&self);
diff --git a/src/test/ui/dyn-star/upcast.stderr b/src/test/ui/dyn-star/upcast.stderr
new file mode 100644
index 00000000000..6a95f7754e6
--- /dev/null
+++ b/src/test/ui/dyn-star/upcast.stderr
@@ -0,0 +1,20 @@
+warning: the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/upcast.rs:3:12
+   |
+LL | #![feature(dyn_star, trait_upcasting)]
+   |            ^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error[E0277]: `dyn* Foo` needs to be a pointer-sized type
+  --> $DIR/upcast.rs:30:23
+   |
+LL |     let w: dyn* Bar = w;
+   |                       ^ `dyn* Foo` needs to be a pointer-sized type
+   |
+   = help: the trait `PointerSized` is not implemented for `dyn* Foo`
+
+error: aborting due to previous error; 1 warning emitted
+
+For more information about this error, try `rustc --explain E0277`.