From ba8e09415b00fdfcda8feeb1cf233f2f065ef6c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Wed, 21 Aug 2019 11:49:51 -0700
Subject: [PATCH] Add clarification on E0308 about opaque types

---
 src/librustc/ty/error.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/librustc/ty/error.rs b/src/librustc/ty/error.rs
index 6daecd7ae94..c1593799286 100644
--- a/src/librustc/ty/error.rs
+++ b/src/librustc/ty/error.rs
@@ -268,6 +268,7 @@ impl<'tcx> TyCtxt<'tcx> {
                     let e_str = values.expected.to_string();
                     let f_str = values.found.to_string();
                     if &e_str == &f_str && &e_str == "impl std::future::Future" {
+                        // FIXME: use non-string based check.
                         db.help("if both futures resolve to the same type, consider `await`ing \
                                  on both of them");
                     }