Rollup merge of #28435 - apasel422:issue-24533, r=nikomatsakis

Closes #24533.

src/test/run-pass/issue-24533.rs

@@ -0,0 +1,32 @@
+// 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.
+
+use std::slice::Iter;
+use std::io::{Error, ErrorKind, Result};
+use std::vec::*;
+
+fn foo(it: &mut Iter<u8>) -> Result<u8> {
+    Ok(*it.next().unwrap())
+}
+
+fn bar() -> Result<u8> {
+    let data: Vec<u8> = Vec::new();
+
+    if true {
+        return Err(Error::new(ErrorKind::NotFound, "msg"));
+    }
+
+    let mut it = data.iter();
+    foo(&mut it)
+}
+
+fn main() {
+    bar();
+}