Add alloc::sync cases

Author: patricklam

doc/src/challenges/new-challenge.md

@@ -61,7 +61,7 @@ All the following pub unsafe functions must be annotated with safety contracts a
 |  Weak<T:?Sized>::from_raw | alloc::sync |
 |  Weak<T:?Sized,A:Allocator>::from_raw_in | alloc::sync |
 
-These (not necessarily public) functions contain unsafe code in their bodies but are not themselves marked unsafe. At least 75% of these should be proven unconditionally safe, or safety contracts should be added.
+These (not necessarily public) functions contain unsafe code in their bodies but are not themselves marked unsafe. At least 75% of these should be proven unconditionally safe, or safety contracts should be added. From alloc::rc:
 
 | Function | Location |
 |---------|---------|
@@ -120,6 +120,70 @@ These (not necessarily public) functions contain unsafe code in their bodies but
 |  UniqueRcUninit<T:?Sized, A:Allocator>::data_ptr | alloc::rc |
 |  Drop<T:?Sized, A:Allocator>::drop for UniqueRcUninit | alloc::rc |
 
+And from alloc::sync:
+
+| Function | Location |
+|---------|---------|
+|  Arc<T:?Sized, A:Allocator>::into_inner_with_allocator   |  alloc::sync   |
+|  Arc<T>::new | alloc::sync |
+|  Arc<T>::new_uninit | alloc::sync |
+|  Arc<T>::new_zeroed | alloc::sync |
+|  Arc<T>::pin | alloc::sync |
+|  Arc<T>::try_pin | alloc::sync |
+|  Arc<T>::try_new | alloc::sync |
+|  Arc<T>::try_new_uninit | alloc::sync |
+|  Arc<T>::try_new_zeroed | alloc::sync |
+|  Arc<T,A:Allocator>::new_in | alloc::sync |
+|  Arc<T,A:Allocator>::new_uninit_in | alloc::sync |
+|  Arc<T,A:Allocator>::new_zeroed_in | alloc::sync |
+|  Arc<T,A:Allocator>::new_cyclic_in | alloc::sync |
+|  Arc<T,A:Allocator>::pin_in | alloc::sync |
+|  Arc<T,A:Allocator>::try_pin_in | alloc::sync |
+|  Arc<T,A:Allocator>::try_new_in | alloc::sync |
+|  Arc<T,A:Allocator>::try_new_uninit_in | alloc::sync |
+|  Arc<T,A:Allocator>::try_new_zeroed_in | alloc::sync |
+|  Arc<T,A:Allocator>::try_unwrap | alloc::sync |
+|  Arc<T,A:Allocator>::into_inner | alloc::sync |
+|  Arc<[T]>::new_uninit_slice | alloc::sync |
+|  Arc<[T]>::new_zeroed_slice | alloc::sync |
+|  Arc<[T]>::into_array | alloc::sync |
+|  Arc<[T],A:Allocator>::new_uninit_slice_in | alloc::sync |
+|  Arc<[T],A:Allocator>::new_zeroed_slice_in | alloc::sync |
+|  Arc<T:?Sized,A:Allocator>::into_raw_with_allocator | alloc::sync |
+|  Arc<T:?Sized,A:Allocator>::as_ptr | alloc::sync |
+|  Arc<T:?Sized,A:Allocator>::inner | alloc::sync |
+|  Arc<T:?Sized,A:Allocator>::from_box_in | alloc::sync |
+|  ArcFromSlice<T: Clone>::from_slice | alloc::sync |
+|  ArcFromSlice<T: Copy>::from_slice | alloc::sync |
+|  Clone<T: ?Sized, A:Allocator>::clone for Arc | alloc::sync |
+|  Arc<T:?Sized+CloneToUninit, A:Allocator+Clone>::make_mut | alloc::sync |
+|  Arc<T:?Sized, A:Allocator>::get_mut | alloc::sync |
+|  Drop<T: ?Sized, A:Allocator>::drop for Arc | alloc::sync |
+|  Arc<dyn Any+Send+Sync,A:Allocator>::downcast | alloc::sync |
+|  Weak<T:?Sized,A:Allocator>::as_ptr | alloc::sync |
+|  Weak<T:?Sized,A:Allocator>::into_raw_with_allocator | alloc::sync |
+|  Weak<T:?Sized,A:Allocator>::upgrade | alloc::sync |
+|  Weak<T:?Sized,A:Allocator>::inner | alloc::sync |
+|  Drop<T:?Sized, A:Allocator>::drop for Weak | alloc::sync |
+|  Default<T:Default>::default | alloc::sync |
+|  Default<str>::default | alloc::sync |
+|  Default<core::ffi::CStr>::default | alloc::sync |
+|  Default<[T]>::default | alloc::sync |
+|  From<&Str>::from | alloc::sync |
+|  From<Vec<T,A:Allocator+Clone>>::from | alloc::sync |
+|  From<Arc<str>>::from | alloc::sync |
+|  TryFrom<Arc[T],A:Allocator>::try_from | alloc::sync |
+|  ToArcSlice<T, I>::to_arc_slice | alloc::sync |
+|  UniqueArcUninit<T:?Sized, A:Allocator>::new | alloc::sync |
+|  UniqueArcUninit<T:?Sized, A:Allocator>::data_ptr | alloc::sync |
+|  Drop<T:?Sized, A:Allocator>::drop for UniqueArcUninit | alloc::sync |
+|  UniqueArc<T:?Sized,A:Allocator>::into_arc | alloc::sync |
+|  UniqueArc<T:?Sized,A:Allocator+Clone>::downgrade | alloc::sync |
+|  Deref<T:?Sized,A:Allocator>::deref | alloc::sync |
+|  DerefMut<T:?Sized,A:Allocator>::deref_mut | alloc::sync |
+|  Drop<T:?Sized, A:Allocator>::drop for UniqueArc | alloc::sync |
+
+
 (I haven't included non-public unsafe functions here, though I do include non-public functions that contain unsafe. Is that a problem? Also, need to add the Arc variants of all these.)
 
 All proofs must automatically ensure the absence of the following undefined behaviors [ref](https://github.com/rust-lang/reference/blob/142b2ed77d33f37a9973772bd95e6144ed9dce43/src/behavior-considered-undefined.md):