Auto merge of #29327 - sanxiyn:argument, r=nrc

Fix #24114.

src/test/compile-fail/borrowck-argument.rs

@@ -0,0 +1,43 @@
+// Copyright 2015 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.
+
+#[derive(Copy, Clone)]
+struct S;
+
+impl S {
+    fn mutate(&mut self) {
+    }
+}
+
+fn func(arg: S) {
+    arg.mutate(); //~ ERROR: cannot borrow immutable argument
+}
+
+impl S {
+    fn method(&self, arg: S) {
+        arg.mutate(); //~ ERROR: cannot borrow immutable argument
+    }
+}
+
+trait T {
+    fn default(&self, arg: S) {
+        arg.mutate(); //~ ERROR: cannot borrow immutable argument
+    }
+}
+
+impl T for S {}
+
+fn main() {
+    let s = S;
+    func(s);
+    s.method(s);
+    s.default(s);
+    (|arg: S| { arg.mutate() })(s); //~ ERROR: cannot borrow immutable argument
+}

src/test/compile-fail/borrowck-closures-unique.rs

@@ -43,7 +43,7 @@ fn d(x: &mut isize) {
 }
 
 fn e(x: &mut isize) {
-    let c1 = || x = panic!(); //~ ERROR closure cannot assign to immutable local variable
+    let c1 = || x = panic!(); //~ ERROR closure cannot assign to immutable argument
 }
 
 fn main() {

src/test/compile-fail/borrowck-unboxed-closures.rs

@@ -17,7 +17,7 @@ fn a<F:Fn(isize, isize) -> isize>(mut f: F) {
 }
 
 fn b<F:FnMut(isize, isize) -> isize>(f: F) {
-    f(1, 2);    //~ ERROR cannot borrow immutable local variable
+    f(1, 2);    //~ ERROR cannot borrow immutable argument
 }
 
 fn c<F:FnOnce(isize, isize) -> isize>(f: F) {