diff options
| -rw-r--r-- | src/libstd/thread/mod.rs | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 4c3980b3c7b..255cd2a9bc0 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -181,6 +181,15 @@ use time::Duration; #[stable(feature = "rust1", since = "1.0.0")] pub use self::local::{LocalKey, LocalKeyState}; +// The types used by the thread_local! macro to access TLS keys. Note that there +// are two types, the "OS" type and the "fast" type. The OS thread local key +// type is accessed via platform-specific API calls and is slow, while the fast +// key type is accessed via code generated via LLVM, where TLS keys are set up +// by the elf linker. Note that the OS TLS type is always available: on macOS +// the standard library is compiled with support for older platform versions +// where fast TLS was not available; end-user code is compiled with fast TLS +// where available, but both are needed. + #[unstable(feature = "libstd_thread_internals", issue = "0")] #[cfg(target_thread_local)] #[doc(hidden)] pub use sys::fast_thread_local::Key as __FastLocalKeyInner; |