diff options
Diffstat (limited to 'src/libstd/thread/local.rs')
| -rw-r--r-- | src/libstd/thread/local.rs | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/src/libstd/thread/local.rs b/src/libstd/thread/local.rs index a53c76a333a..cb18eed8ee5 100644 --- a/src/libstd/thread/local.rs +++ b/src/libstd/thread/local.rs @@ -325,7 +325,10 @@ impl<T: 'static> LocalKey<T> { /// /// Once the initialization expression succeeds, the key transitions to the /// `Valid` state which will guarantee that future calls to [`with`] will - /// succeed within the thread. + /// succeed within the thread. Some keys might skip the `Uninitialized` + /// state altogether and start in the `Valid` state as an optimization + /// (e.g. keys initialized with a constant expression), but no guarantees + /// are made. /// /// When a thread exits, each key will be destroyed in turn, and as keys are /// destroyed they will enter the `Destroyed` state just before the |