std: Re-enable at_exit()

The new semantics of this function are that the callbacks are run when the *main
thread* exits, not when all threads have exited. This implies that other threads
may still be running when the `at_exit` callbacks are invoked and users need to
be prepared for this situation.

Users in the standard library have been audited in accordance to these new rules
as well.

Closes #20012

1 files changed, 2 insertions, 2 deletions

diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 8274baeacfa..5c70340fe10 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -228,13 +228,13 @@ pub mod thread;
 pub mod sync;
 pub mod comm;
 
+#[path = "sys/common/mod.rs"] mod sys_common;
+
 #[cfg(unix)]
 #[path = "sys/unix/mod.rs"] mod sys;
 #[cfg(windows)]
 #[path = "sys/windows/mod.rs"] mod sys;
 
-#[path = "sys/common/mod.rs"] mod sys_common;
-
 pub mod rt;
 mod failure;