added non-poison mutex

Author: Aandreba

library/std/src/sync/mod.rs

@@ -202,6 +202,8 @@ pub use self::rwlock::{RwLock, RwLockReadGuard, RwLockWriteGuard};
 #[unstable(feature = "mpmc_channel", issue = "126840")]
 pub mod mpmc;
 pub mod mpsc;
+#[unstable(feature = "sync_nonpoison", issue = "134645")]
+pub mod nonpoison;
 
 mod barrier;
 mod condvar;

library/std/src/sync/nonpoison/mod.rs

@@ -0,0 +1,10 @@
+//! Non-poisoning syncronous locks.
+//!
+//! The locks found on this module will not become poisoned when a thread panics whilst holding a guard.
+
+#[unstable(feature = "sync_nonpoison", issue = "134645")]
+pub use self::mutex::MappedMutexGuard;
+#[unstable(feature = "sync_nonpoison", issue = "134645")]
+pub use self::mutex::{Mutex, MutexGuard};
+
+mod mutex;