Added fully elaborated type label for inferred arguments.

src/test/ui/issue-52533.nll.stderr

@@ -0,0 +1,17 @@
+warning: not reporting region error due to nll
+  --> $DIR/issue-52533.rs:15:16
+   |
+LL |     foo(|a, b| b)
+   |                ^
+
+error: unsatisfied lifetime constraints
+  --> $DIR/issue-52533.rs:15:16
+   |
+LL |     foo(|a, b| b)
+   |          -  -  ^ free region requires that `'1` must outlive `'2`
+   |          |  |
+   |          |  lifetime `'1` appears in this argument
+   |          lifetime `'2` appears in this argument
+
+error: aborting due to previous error
+

src/test/ui/issue-52533.rs

@@ -0,0 +1,17 @@
+// Copyright 2018 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.
+
+fn foo(_: impl for<'a> FnOnce(&'a u32, &u32) -> &'a u32) {
+}
+
+fn main() {
+    foo(|a, b| b)
+    //~^ ERROR lifetime of reference outlives lifetime of borrowed content...
+}

src/test/ui/issue-52533.stderr

@@ -0,0 +1,20 @@
+error[E0312]: lifetime of reference outlives lifetime of borrowed content...
+  --> $DIR/issue-52533.rs:15:16
+   |
+LL |     foo(|a, b| b)
+   |                ^
+   |
+note: ...the reference is valid for the anonymous lifetime #2 defined on the body at 15:9...
+  --> $DIR/issue-52533.rs:15:9
+   |
+LL |     foo(|a, b| b)
+   |         ^^^^^^^^
+note: ...but the borrowed content is only valid for the anonymous lifetime #3 defined on the body at 15:9
+  --> $DIR/issue-52533.rs:15:9
+   |
+LL |     foo(|a, b| b)
+   |         ^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0312`.