1 files changed, 2 insertions, 0 deletions
diff --git a/src/libcore/sync/atomic.rs b/src/libcore/sync/atomic.rs
index 75ddd2021a8..a5efda702df 100644
--- a/src/libcore/sync/atomic.rs
+++ b/src/libcore/sync/atomic.rs
@@ -95,6 +95,7 @@ pub struct AtomicBool {
 #[cfg(target_has_atomic = "8")]
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Default for AtomicBool {
+    /// Creates an `AtomicBool` initialised as false.
     fn default() -> Self {
         Self::new(false)
     }
@@ -117,6 +118,7 @@ pub struct AtomicPtr<T> {
 #[cfg(target_has_atomic = "ptr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Default for AtomicPtr<T> {
+    /// Creates an `AtomicPtr<T>` with an initial mutable null pointer.
     fn default() -> AtomicPtr<T> {
         AtomicPtr::new(::ptr::null_mut())
     }