std: clean up the TLS implementation

library/std/src/sys/mod.rs

@@ -9,8 +9,6 @@ pub mod cmath;
 pub mod os_str;
 pub mod path;
 pub mod sync;
-#[allow(dead_code)]
-#[allow(unused_imports)]
 pub mod thread_local;
 
 // FIXME(117276): remove this, move feature implementations into individual

library/std/src/sys/thread_local/fast_local/lazy.rs

@@ -1,6 +1,5 @@
 use crate::cell::UnsafeCell;
 use crate::hint::unreachable_unchecked;
-use crate::mem::forget;
 use crate::ptr;
 use crate::sys::thread_local::abort_on_dtor_unwind;
 use crate::sys::thread_local_dtor::register_dtor;

library/std/src/sys/thread_local/mod.rs

@@ -1,4 +1,5 @@
 #![unstable(feature = "thread_local_internals", reason = "should not be necessary", issue = "none")]
+#![cfg(not(test))]
 
 // There are three thread-local implementations: "static", "fast", "OS".
 // The "OS" thread local key type is accessed via platform-specific API calls and is slow, while the
@@ -28,7 +29,8 @@ cfg_if::cfg_if! {
 /// fn` declared in a user crate). If the callback unwinds anyway, then
 /// `rtabort` with a message about thread local panicking on drop.
 #[inline]
-pub fn abort_on_dtor_unwind(f: impl FnOnce()) {
+#[allow(dead_code)]
+fn abort_on_dtor_unwind(f: impl FnOnce()) {
     // Using a guard like this is lower cost.
     let guard = DtorUnwindGuard;
     f();

library/std/src/sys/thread_local/os_local.rs

@@ -1,8 +1,8 @@
 use super::abort_on_dtor_unwind;
 use crate::cell::Cell;
 use crate::marker::PhantomData;
+use crate::ptr;
 use crate::sys_common::thread_local_key::StaticKey as OsKey;
-use crate::{panic, ptr};
 
 #[doc(hidden)]
 #[allow_internal_unstable(thread_local_internals)]