From edae4958556a6150841b9964b322d1e96e7a4586 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Mon, 6 Jun 2022 13:55:43 +0200
Subject: [PATCH] Make {Mutex, Condvar, RwLock}::new() const.

---
 library/std/src/sync/condvar.rs      | 1 +
 library/std/src/sync/mutex.rs        | 1 +
 library/std/src/sync/rwlock.rs       | 1 +
 library/std/src/sys_common/mutex.rs  | 2 +-
 library/std/src/sys_common/rwlock.rs | 2 +-
 5 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/library/std/src/sync/condvar.rs b/library/std/src/sync/condvar.rs
index a1d7b6ff06174..eb1e7135a6e41 100644
--- a/library/std/src/sync/condvar.rs
+++ b/library/std/src/sync/condvar.rs
@@ -122,6 +122,7 @@ impl Condvar {
     /// let condvar = Condvar::new();
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
     #[must_use]
     #[inline]
     pub const fn new() -> Condvar {
diff --git a/library/std/src/sync/mutex.rs b/library/std/src/sync/mutex.rs
index d63f81e68c815..37d4454534d17 100644
--- a/library/std/src/sync/mutex.rs
+++ b/library/std/src/sync/mutex.rs
@@ -214,6 +214,7 @@ impl<T> Mutex<T> {
     /// let mutex = Mutex::new(0);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
     #[inline]
     pub const fn new(t: T) -> Mutex<T> {
         Mutex {
diff --git a/library/std/src/sync/rwlock.rs b/library/std/src/sync/rwlock.rs
index ce62c022ae08b..9fee42e236215 100644
--- a/library/std/src/sync/rwlock.rs
+++ b/library/std/src/sync/rwlock.rs
@@ -146,6 +146,7 @@ impl<T> RwLock<T> {
     /// let lock = RwLock::new(5);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
     #[inline]
     pub const fn new(t: T) -> RwLock<T> {
         RwLock {
diff --git a/library/std/src/sys_common/mutex.rs b/library/std/src/sys_common/mutex.rs
index daba9c3f2b69c..81eefa1133fa5 100644
--- a/library/std/src/sys_common/mutex.rs
+++ b/library/std/src/sys_common/mutex.rs
@@ -62,7 +62,7 @@ unsafe impl Sync for MovableMutex {}
 impl MovableMutex {
     /// Creates a new mutex.
     #[inline]
-    pub fn new() -> Self {
+    pub const fn new() -> Self {
         Self(imp::MovableMutex::new())
     }
 
diff --git a/library/std/src/sys_common/rwlock.rs b/library/std/src/sys_common/rwlock.rs
index b455074709288..265cebfdc3e0a 100644
--- a/library/std/src/sys_common/rwlock.rs
+++ b/library/std/src/sys_common/rwlock.rs
@@ -75,7 +75,7 @@ pub struct MovableRwLock(imp::MovableRwLock);
 impl MovableRwLock {
     /// Creates a new reader-writer lock for use.
     #[inline]
-    pub fn new() -> Self {
+    pub const fn new() -> Self {
         Self(imp::MovableRwLock::new())
     }