================
@@ -0,0 +1,48 @@
+.. title:: clang-tidy - misc-coroutine-hostile-raii
+
+misc-coroutine-hostile-raii
+====================
+
+This check detects hostile-RAII objects which should not persist across a
+suspension point in a coroutine.
+
+Some objects require that they be destroyed on the same thread that created
them.
+Traditionally this requirement was often phrased as "must be a local variable",
+under the assumption that local variables always work this way. However this is
+incorrect with C++20 coroutines, since an intervening `co_await` may cause the
+coroutine to suspend and later be resumed on another thread.
+
+The lifetime of an object that requires being destroyed on the same thread
must
+not encompass a `co_await` or `co_yield` point. If you create/destroy an
object,
+you must do so without allowing the coroutine to suspend in the meantime.
+
+The check considers the following type as hostile:
+
+ - Scoped-lockable types: A scoped-lockable object persisting across a
suspension
+ point is problematic as the lock held by this object could be unlocked by a
+ different thread. This would be undefined behaviour.
+
+ - Types belonging to a configurable denylist.
+
+.. code-block:: c++
+
+ // Call some async API while holding a lock.
+ {
+ const my::MutexLock l(&mu_);
+
+ // Oops! The async Bar function may finish on a different
+ // thread from the one that created the MutexLock object and therefore
called
+ // Mutex::Lock -- now Mutex::Unlock will be called on the wrong thread.
+ co_await Bar();
+ }
+
+
+Options
+-------
+
+.. option:: RAIIDenyList
+
+ A semicolon-separated list of qualified types which should not be allowed
to
+ persist across suspension points.
----------------
PiotrZSL wrote:
do not wrap line on "Do"
https://github.com/llvm/llvm-project/pull/68738
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