Move /src/test to /tests

tests/ui/uninit-empty-types.rs

@@ -0,0 +1,19 @@
+// build-pass
+// Test the uninit() construct returning various empty types.
+
+// pretty-expanded FIXME #23616
+
+use std::mem::MaybeUninit;
+
+struct Foo;
+
+#[allow(deprecated)]
+pub fn main() {
+    unsafe {
+        // `Foo` and `[Foo; 2]` are both zero sized and inhabited, so this is safe.
+        let _x: Foo = MaybeUninit::uninit().assume_init();
+        let _x: [Foo; 2] = MaybeUninit::uninit().assume_init();
+        let _x: Foo = std::mem::uninitialized();
+        let _x: [Foo; 2] = std::mem::uninitialized();
+    }
+}