Relocate Arc and Rc UnwindSafe impls

Author: dtolnay

library/alloc/src/lib.rs

@@ -177,7 +177,6 @@ mod boxed {
 pub mod borrow;
 pub mod collections;
 pub mod fmt;
-mod panic;
 pub mod prelude;
 pub mod raw_vec;
 pub mod rc;

library/alloc/src/panic.rs

@@ -262,6 +262,7 @@ use core::marker::{self, PhantomData, Unpin, Unsize};
 use core::mem::size_of_val;
 use core::mem::{self, align_of_val_raw, forget};
 use core::ops::{CoerceUnsized, Deref, DispatchFromDyn, Receiver};
+use core::panic::{RefUnwindSafe, UnwindSafe};
 #[cfg(not(no_global_oom_handling))]
 use core::pin::Pin;
 use core::ptr::{self, NonNull};
@@ -314,6 +315,9 @@ impl<T: ?Sized> !marker::Send for Rc<T> {}
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: ?Sized> !marker::Sync for Rc<T> {}
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl<T: RefUnwindSafe + ?Sized> UnwindSafe for Rc<T> {}
+
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Rc<U>> for Rc<T> {}
 

library/alloc/src/rc.rs

@@ -19,6 +19,7 @@ use core::marker::{PhantomData, Unpin, Unsize};
 use core::mem::size_of_val;
 use core::mem::{self, align_of_val_raw};
 use core::ops::{CoerceUnsized, Deref, DispatchFromDyn, Receiver};
+use core::panic::{RefUnwindSafe, UnwindSafe};
 use core::pin::Pin;
 use core::ptr::{self, NonNull};
 #[cfg(not(no_global_oom_handling))]
@@ -240,6 +241,9 @@ unsafe impl<T: ?Sized + Sync + Send> Send for Arc<T> {}
 #[stable(feature = "rust1", since = "1.0.0")]
 unsafe impl<T: ?Sized + Sync + Send> Sync for Arc<T> {}
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl<T: RefUnwindSafe + ?Sized> UnwindSafe for Arc<T> {}
+
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Arc<U>> for Arc<T> {}