1 files changed, 34 insertions, 0 deletions
diff --git a/src/test/ui/cast/fat-ptr-cast-rpass.rs b/src/test/ui/cast/fat-ptr-cast-rpass.rs
new file mode 100644
index 000000000..f5747eb8b
--- /dev/null
+++ b/src/test/ui/cast/fat-ptr-cast-rpass.rs
@@ -0,0 +1,34 @@
+// run-pass
+
+#![feature(ptr_metadata)]
+
+trait Foo {
+    fn foo(&self) {}
+}
+
+struct Bar;
+
+impl Foo for Bar {}
+
+fn main() {
+    // Test we can turn a fat pointer to array back into a thin pointer.
+    let a: *const [i32] = &[1, 2, 3];
+    let b = a as *const [i32; 2];
+    unsafe {
+        assert_eq!(*b, [1, 2]);
+    }
+
+    // Test conversion to an address (usize).
+    let a: *const [i32; 3] = &[1, 2, 3];
+    let b: *const [i32] = a;
+    assert_eq!(a as usize, b as *const () as usize);
+
+    // And conversion to a void pointer/address for trait objects too.
+    let a: *mut dyn Foo = &mut Bar;
+    let b = a as *mut () as usize;
+    let c = a as *const () as usize;
+    let d = a.to_raw_parts().0 as usize;
+
+    assert_eq!(b, d);
+    assert_eq!(c, d);
+}