Test against accesses to uninitialized fields.

src/test/compile-fail/borrowck/borrowck-uninit-field-access.rs

@@ -0,0 +1,49 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// revisions: ast mir
+//[mir]compile-flags: -Z emit-end-regions -Z borrowck-mir
+
+// Check that do not allow access to fields of uninitialized or moved
+// structs.
+
+#[derive(Default)]
+struct Point {
+    x: isize,
+    y: isize,
+}
+
+#[derive(Default)]
+struct Line {
+    origin: Point,
+    middle: Point,
+    target: Point,
+}
+
+impl Line { fn consume(self) { } }
+
+fn main() {
+    let mut a: Point;
+    let _ = a.x + 1; //[ast]~ ERROR use of possibly uninitialized variable: `a.x`
+                     //[mir]~^ ERROR       [E0381]
+                     //[mir]~| ERROR (Mir) [E0381]
+
+    let mut line1 = Line::default();
+    let _moved = line1.origin;
+    let _ = line1.origin.x + 1; //[ast]~ ERROR use of collaterally moved value: `line1.origin.x`
+                                //[mir]~^       [E0382]
+                                //[mir]~| (Mir) [E0381]
+
+    let mut line2 = Line::default();
+    let _moved = (line2.origin, line2.middle);
+    line2.consume(); //[ast]~ ERROR use of partially moved value: `line2` [E0382]
+                     //[mir]~^       [E0382]
+                     //[mir]~| (Mir) [E0381]
+}