Regression test for #17740

Closes #17740.

src/test/compile-fail/issue-17740.rs

@@ -0,0 +1,22 @@
+// Copyright 2014 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.
+
+struct Foo<'a> {
+    data: &'a[u8],
+}
+
+impl <'a> Foo<'a>{
+    fn bar(self: &mut Foo) {
+    //~^ mismatched types: expected `Foo<'a>`, found `Foo<'_>` (lifetime mismatch)
+    //~| mismatched types: expected `Foo<'a>`, found `Foo<'_>` (lifetime mismatch)
+    }
+}
+
+fn main() {}