vendor/arc-swap-1.6.0/CHANGELOG.md - toolchain/rustc - Git at Google

 # 1.6.0

 * Fix a data race reported by MIRI.
 * Avoid violating stacked borrows (AFAIK these are still experimental and not
   normative, but better safe than sorry). (#80).
 * The `AccessConvert` wrapper is needed less often in practice (#77).

 # 1.5.1

 * bug: Insufficient synchronization on weak platforms (#76).

   Never observed in practice (it's suspected practical weak platforms like ARM
   are still stronger than the model), but still technically UB.
 * docs: Mention triomphe's `ThinArc` around the fat-pointer limitations.

 # 1.5.0

 * Support serde (by a feature).

 # 1.4.0

 * Allow const-initializing ArcSwapOption (`const_empty` method).

 # 1.3.2

 * More helpful description of the `AsRaw` trait (isn't implemented for owned
   `Arc`/`Option<Arc>`).

 # 1.3.1

 * Cache doc improvements.

 # 1.3.0

 * Allow mapping of DynAccess.
 * Fix some lints.
 * Don't leave threads running in tests/doctests. It's a bad form and annoys
   miri.

 # 1.2.0

 * Miri and 32 bit tests in CI.
 * Making the writers lock-free. Soft-removing the IndependentStrategy, as it is
   no longer needed (hidden and the same as the DafultStrategy).

 # 1.1.0

 * Fix soundness bug around access::Map. Technically a breaking change, but
   unlikely to bite and breaking seems to be the least bad option. #45.

 # 1.0.0

 * Remove Clone implementation. People are often confused by it and it is easy to
   emulate by hand in the rare case it is actually needed.

 # 1.0.0-rc1

 * Get rid of the `load_signal_safe`. It only complicates things and it is niche;
   signal-hook-registry has its own simplified version.
 * Avoid `from_ptr(as_ptr())`. Slight change in `RefCnt::inc` which technically
   is API breaking change, but this one should not matter in practice.
 * Extend documentation about clone behaviour.
 * Few more traits for Guard (`From<T: RefCnt>`, `Default`).
 * Get rid of `rcu_unwap`, the whole concept is a trap.
 * Hide the whole gen lock thing.
 * Introduce the `Strategy`, as a high level way to choose how exactly the
   locking happens.
   - Not possible to implement by downstream users just yet, or call them.
   - The CaS is its own trait for flexibility.
 * Adding the SimpleGenLock experimental strategy.
   - Not part of stability guarantees.

 # 0.4.7

 * Rename the `unstable-weak` to `weak` feature. The support is now available on
   1.45 (currently in beta).

 # 0.4.6

 * Adjust to `Weak::as_ptr` from std (the weak pointer support, relying on
   unstable features).
 * Support running on miri (without some optimizations), so dependencies may run
   miri tests.
 * Little optimization when waiting out the contention on write operations.

 # 0.4.5

 * Added `Guard::from_inner`.

 # 0.4.4

 * Top-level docs rewrite (less rambling, hopefully more readable).

 # 0.4.3

 * Fix the `Display` implementation on `Guard` to correctly delegate to the
   underlying `Display` implementation.

 # 0.4.2

 * The Access functionality ‒ ability to pass a handle to subpart of held data to
   somewhere with the ability to update itself.
 * Mapped cache can take `FnMut` as well as `Fn`.

 # 0.4.1

 * Mapped caches ‒ to allow giving access to parts of config only.

 # 0.4.0

 * Support for Weak pointers.
 * RefCnt implemented for Rc.
 * Breaking: Big API cleanups.
   - Peek is gone.
   - Terminology of getting the data unified to `load`.
   - There's only one kind of `Guard` now.
   - Guard derefs to the `Arc`/`Option<Arc>` or similar.
   - `Cache` got moved to top level of the crate.
   - Several now unneeded semi-internal traits and trait methods got removed.
 * Splitting benchmarks into a separate sub-crate.
 * Minor documentation improvements.

 # 0.3.11

 * Prevention against UB due to dropping Guards and overflowing the guard
   counter (aborting instead, such problem is very degenerate anyway and wouldn't
   work in the first place).

 # 0.3.10

 * Tweak slot allocation to take smaller performance hit if some leases are held.
 * Increase the number of lease slots per thread to 8.
 * Added a cache for faster access by keeping an already loaded instance around.

 # 0.3.9

 * Fix Send/Sync for Guard and Lease (they were broken in the safe but
   uncomfortable direction ‒ not implementing them even if they could).

 # 0.3.8

 * `Lease<Option<_>>::unwrap()`, `expect()` and `into_option()` for convenient
   use.

 # 0.3.7

 * Use the correct `#[deprecated]` syntax.

 # 0.3.6

 * Another locking store (`PrivateSharded`) to complement the global and private
   unsharded ones.
 * Comparison to other crates/approaches in the docs.

 # 0.3.5

 * Updates to documentation, made it hopefully easier to digest.
 * Added the ability to separate gen-locks of one ArcSwapAny from others.
 * Some speed improvements by inlining.
 * Simplified the `lease` method internally, making it faster in optimistic
   cases.

 # 0.3.4

 * Another potentially weak ordering discovered (with even less practical effect
   than the previous).

 # 0.3.3

 * Increased potentially weak ordering (probably without any practical effect).

 # 0.3.2

 * Documentation link fix.

 # 0.3.1

 * Few convenience constructors.
 * More tests (some randomized property testing).

 # 0.3.0

 * `compare_and_swap` no longer takes `&Guard` as current as that is a sure way
   to create a deadlock.
 * Introduced `Lease` for temporary storage, which doesn't suffer from contention
   like `load`, but doesn't block writes like `Guard`. The downside is it slows
   down with number of held by the current thread.
 * `compare_and_swap` and `rcu` uses leases.
 * Made the `ArcSwap` as small as the pointer itself, by making the
   shards/counters and generation ID global. This comes at a theoretical cost of
   more contention when different threads use different instances.

 # 0.2.0

 * Added an `ArcSwapOption`, which allows storing NULL values (as None) as well
   as a valid pointer.
 * `compare_and_swap` accepts borrowed `Arc` as `current` and doesn't consume one
   ref count.
 * Sharding internal counters, to improve performance on read-mostly contented
   scenarios.
 * Providing `peek_signal_safe` as the only async signal safe method to use
   inside signal handlers. This removes the footgun with dropping the `Arc`
   returned from `load` inside a signal handler.

 # 0.1.4

 * The `peek` method to use the `Arc` inside without incrementing the reference
   count.
 * Some more (and hopefully better) benchmarks.

 # 0.1.3

 * Documentation fix (swap is *not* lock-free in current implementation).

 # 0.1.2

 * More freedom in the `rcu` and `rcu_unwrap` return types.

 # 0.1.1

 * `rcu` support.
 * `compare_and_swap` support.
 * Added some primitive benchmarks.

 # 0.1.0

 * Initial implementation.
	# 1.6.0

	* Fix a data race reported by MIRI.
	* Avoid violating stacked borrows (AFAIK these are still experimental and not
	normative, but better safe than sorry). (#80).
	* The `AccessConvert` wrapper is needed less often in practice (#77).

	# 1.5.1

	* bug: Insufficient synchronization on weak platforms (#76).

	Never observed in practice (it's suspected practical weak platforms like ARM
	are still stronger than the model), but still technically UB.
	* docs: Mention triomphe's `ThinArc` around the fat-pointer limitations.

	# 1.5.0

	* Support serde (by a feature).

	# 1.4.0

	* Allow const-initializing ArcSwapOption (`const_empty` method).

	# 1.3.2

	* More helpful description of the `AsRaw` trait (isn't implemented for owned
	`Arc`/`Option<Arc>`).

	# 1.3.1

	* Cache doc improvements.

	# 1.3.0

	* Allow mapping of DynAccess.
	* Fix some lints.
	* Don't leave threads running in tests/doctests. It's a bad form and annoys
	miri.

	# 1.2.0

	* Miri and 32 bit tests in CI.
	* Making the writers lock-free. Soft-removing the IndependentStrategy, as it is
	no longer needed (hidden and the same as the DafultStrategy).

	# 1.1.0

	* Fix soundness bug around access::Map. Technically a breaking change, but
	unlikely to bite and breaking seems to be the least bad option. #45.

	# 1.0.0

	* Remove Clone implementation. People are often confused by it and it is easy to
	emulate by hand in the rare case it is actually needed.

	# 1.0.0-rc1

	* Get rid of the `load_signal_safe`. It only complicates things and it is niche;
	signal-hook-registry has its own simplified version.
	* Avoid `from_ptr(as_ptr())`. Slight change in `RefCnt::inc` which technically
	is API breaking change, but this one should not matter in practice.
	* Extend documentation about clone behaviour.
	* Few more traits for Guard (`From<T: RefCnt>`, `Default`).
	* Get rid of `rcu_unwap`, the whole concept is a trap.
	* Hide the whole gen lock thing.
	* Introduce the `Strategy`, as a high level way to choose how exactly the
	locking happens.
	- Not possible to implement by downstream users just yet, or call them.
	- The CaS is its own trait for flexibility.
	* Adding the SimpleGenLock experimental strategy.
	- Not part of stability guarantees.

	# 0.4.7

	* Rename the `unstable-weak` to `weak` feature. The support is now available on
	1.45 (currently in beta).

	# 0.4.6

	* Adjust to `Weak::as_ptr` from std (the weak pointer support, relying on
	unstable features).
	* Support running on miri (without some optimizations), so dependencies may run
	miri tests.
	* Little optimization when waiting out the contention on write operations.

	# 0.4.5

	* Added `Guard::from_inner`.

	# 0.4.4

	* Top-level docs rewrite (less rambling, hopefully more readable).

	# 0.4.3

	* Fix the `Display` implementation on `Guard` to correctly delegate to the
	underlying `Display` implementation.

	# 0.4.2

	* The Access functionality ‒ ability to pass a handle to subpart of held data to
	somewhere with the ability to update itself.
	* Mapped cache can take `FnMut` as well as `Fn`.

	# 0.4.1

	* Mapped caches ‒ to allow giving access to parts of config only.

	# 0.4.0

	* Support for Weak pointers.
	* RefCnt implemented for Rc.
	* Breaking: Big API cleanups.
	- Peek is gone.
	- Terminology of getting the data unified to `load`.
	- There's only one kind of `Guard` now.
	- Guard derefs to the `Arc`/`Option<Arc>` or similar.
	- `Cache` got moved to top level of the crate.
	- Several now unneeded semi-internal traits and trait methods got removed.
	* Splitting benchmarks into a separate sub-crate.
	* Minor documentation improvements.

	# 0.3.11

	* Prevention against UB due to dropping Guards and overflowing the guard
	counter (aborting instead, such problem is very degenerate anyway and wouldn't
	work in the first place).

	# 0.3.10

	* Tweak slot allocation to take smaller performance hit if some leases are held.
	* Increase the number of lease slots per thread to 8.
	* Added a cache for faster access by keeping an already loaded instance around.

	# 0.3.9

	* Fix Send/Sync for Guard and Lease (they were broken in the safe but
	uncomfortable direction ‒ not implementing them even if they could).

	# 0.3.8

	* `Lease<Option<_>>::unwrap()`, `expect()` and `into_option()` for convenient
	use.

	# 0.3.7

	* Use the correct `#[deprecated]` syntax.

	# 0.3.6

	* Another locking store (`PrivateSharded`) to complement the global and private
	unsharded ones.
	* Comparison to other crates/approaches in the docs.

	# 0.3.5

	* Updates to documentation, made it hopefully easier to digest.
	* Added the ability to separate gen-locks of one ArcSwapAny from others.
	* Some speed improvements by inlining.
	* Simplified the `lease` method internally, making it faster in optimistic
	cases.

	# 0.3.4

	* Another potentially weak ordering discovered (with even less practical effect
	than the previous).

	# 0.3.3

	* Increased potentially weak ordering (probably without any practical effect).

	# 0.3.2

	* Documentation link fix.

	# 0.3.1

	* Few convenience constructors.
	* More tests (some randomized property testing).

	# 0.3.0

	* `compare_and_swap` no longer takes `&Guard` as current as that is a sure way
	to create a deadlock.
	* Introduced `Lease` for temporary storage, which doesn't suffer from contention
	like `load`, but doesn't block writes like `Guard`. The downside is it slows
	down with number of held by the current thread.
	* `compare_and_swap` and `rcu` uses leases.
	* Made the `ArcSwap` as small as the pointer itself, by making the
	shards/counters and generation ID global. This comes at a theoretical cost of
	more contention when different threads use different instances.

	# 0.2.0

	* Added an `ArcSwapOption`, which allows storing NULL values (as None) as well
	as a valid pointer.
	* `compare_and_swap` accepts borrowed `Arc` as `current` and doesn't consume one
	ref count.
	* Sharding internal counters, to improve performance on read-mostly contented
	scenarios.
	* Providing `peek_signal_safe` as the only async signal safe method to use
	inside signal handlers. This removes the footgun with dropping the `Arc`
	returned from `load` inside a signal handler.

	# 0.1.4

	* The `peek` method to use the `Arc` inside without incrementing the reference
	count.
	* Some more (and hopefully better) benchmarks.

	# 0.1.3

	* Documentation fix (swap is not lock-free in current implementation).

	# 0.1.2

	* More freedom in the `rcu` and `rcu_unwrap` return types.

	# 0.1.1

	* `rcu` support.
	* `compare_and_swap` support.
	* Added some primitive benchmarks.

	# 0.1.0

	* Initial implementation.