From 5eed95ede9d68e9c18c5798aad60b5f94b8a213b Mon Sep 17 00:00:00 2001
From: Eduard-Mihai Burtescu <edy.burt@gmail.com>
Date: Sat, 25 Nov 2017 14:08:59 +0200
Subject: [PATCH] rustc_trans: don't apply noalias on returned references.

---
 src/librustc_trans/abi.rs              |  3 ++-
 src/test/run-make/issue-46239/Makefile |  5 +++++
 src/test/run-make/issue-46239/main.rs  | 18 ++++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 src/test/run-make/issue-46239/Makefile
 create mode 100644 src/test/run-make/issue-46239/main.rs

diff --git a/src/librustc_trans/abi.rs b/src/librustc_trans/abi.rs
index 54828044de670..1cd138d4ee6e9 100644
--- a/src/librustc_trans/abi.rs
+++ b/src/librustc_trans/abi.rs
@@ -792,7 +792,8 @@ impl<'a, 'tcx> FnType<'tcx> {
                     // dependencies rather than pointer equality
                     let no_alias = match kind {
                         PointerKind::Shared => false,
-                        PointerKind::Frozen | PointerKind::UniqueOwned => true,
+                        PointerKind::UniqueOwned => true,
+                        PointerKind::Frozen |
                         PointerKind::UniqueBorrowed => !is_return
                     };
                     if no_alias {
diff --git a/src/test/run-make/issue-46239/Makefile b/src/test/run-make/issue-46239/Makefile
new file mode 100644
index 0000000000000..698a605f7e9ba
--- /dev/null
+++ b/src/test/run-make/issue-46239/Makefile
@@ -0,0 +1,5 @@
+-include ../tools.mk
+
+all:
+	$(RUSTC) main.rs -C opt-level=1
+	$(call RUN,main)
diff --git a/src/test/run-make/issue-46239/main.rs b/src/test/run-make/issue-46239/main.rs
new file mode 100644
index 0000000000000..3b3289168abe9
--- /dev/null
+++ b/src/test/run-make/issue-46239/main.rs
@@ -0,0 +1,18 @@
+// Copyright 2017 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 project<T>(x: &(T,)) -> &T { &x.0 }
+
+fn dummy() {}
+
+fn main() {
+    let f = (dummy as fn(),);
+    (*project(&f))();
+}