From 2fb5d5df89897115cb4c7fba6b8da41ed665f75d Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge@japaric.io>
Date: Sun, 9 Sep 2018 15:43:28 +0200
Subject: [PATCH] stabilize `#[used]`

closes #40289
---
 src/libstd/lib.rs                          |  2 +-
 src/libsyntax/feature_gate.rs              | 11 ++++-------
 src/test/run-make-fulldeps/used/used.rs    |  1 -
 src/test/ui/run-pass/issues/issue-41628.rs |  1 -
 src/test/ui/used.rs                        |  2 --
 5 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 4278926b042..5c9e88dc57c 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -307,7 +307,7 @@
 #![feature(doc_cfg)]
 #![feature(doc_masked)]
 #![feature(doc_spotlight)]
-#![cfg_attr(windows, feature(used))]
+#![cfg_attr(all(windows, stage0), feature(used))]
 #![feature(doc_alias)]
 #![feature(doc_keyword)]
 #![feature(panic_info_message)]
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 0270e36db11..cbadbf8ee16 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -349,9 +349,6 @@ pub fn walk_feature_fields<F>(&self, mut f: F)
     // Allows the `try {...}` expression
     (active, try_blocks, "1.29.0", Some(31436), None),
 
-    // Used to preserve symbols (see llvm.used)
-    (active, used, "1.18.0", Some(40289), None),
-
     // Allows module-level inline assembly by way of global_asm!()
     (active, global_asm, "1.18.0", Some(35119), None),
 
@@ -674,6 +671,9 @@ pub fn walk_feature_fields<F>(&self, mut f: F)
     // Allows all literals in attribute lists and values of key-value pairs.
     (accepted, attr_literals, "1.30.0", Some(34981), None),
     (accepted, panic_handler, "1.30.0", Some(44489), None),
+    // Used to preserve symbols (see llvm.used)
+    (accepted, used, "1.29.0", Some(40289), None),
+
 );
 
 // If you change this, please modify src/doc/unstable-book as well. You must
@@ -1064,10 +1064,7 @@ pub fn is_builtin_attr(attr: &ast::Attribute) -> bool {
                                   "unwind_attributes",
                                   "#[unwind] is experimental",
                                   cfg_fn!(unwind_attributes))),
-    ("used", Whitelisted, Gated(
-        Stability::Unstable, "used",
-        "the `#[used]` attribute is an experimental feature",
-        cfg_fn!(used))),
+    ("used", Whitelisted, Ungated),
 
     // used in resolve
     ("prelude_import", Whitelisted, Gated(Stability::Unstable,
diff --git a/src/test/run-make-fulldeps/used/used.rs b/src/test/run-make-fulldeps/used/used.rs
index 186cd0fdf5e..6992dd94af3 100644
--- a/src/test/run-make-fulldeps/used/used.rs
+++ b/src/test/run-make-fulldeps/used/used.rs
@@ -9,7 +9,6 @@
 // except according to those terms.
 
 #![crate_type = "lib"]
-#![feature(used)]
 
 #[used]
 static FOO: u32 = 0;
diff --git a/src/test/ui/run-pass/issues/issue-41628.rs b/src/test/ui/run-pass/issues/issue-41628.rs
index 75924274f1c..f4b9588ff05 100644
--- a/src/test/ui/run-pass/issues/issue-41628.rs
+++ b/src/test/ui/run-pass/issues/issue-41628.rs
@@ -10,7 +10,6 @@
 
 // run-pass
 #![deny(dead_code)]
-#![feature(used)]
 
 #[used]
 static FOO: u32 = 0;
diff --git a/src/test/ui/used.rs b/src/test/ui/used.rs
index f170d9c25f5..b3ed8601988 100644
--- a/src/test/ui/used.rs
+++ b/src/test/ui/used.rs
@@ -8,8 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(used)]
-
 #[used]
 static FOO: u32 = 0; // OK
 
-- 
2.44.0