waitQueue.compare_exchange_strong in the true loop can be weak

weak is more suitable for this while loop than strong.

Author: AZero13

stdlib/public/Concurrency/TaskGroup.cpp

@@ -1786,7 +1786,7 @@ reevaluate_if_taskgroup_has_results:;
     }
     // Put the waiting task at the beginning of the wait queue.
     SWIFT_TASK_GROUP_DEBUG_LOG(this, "WATCH OUT, SET WAITER ONTO waitQueue.head = %p", waitQueue.load(std::memory_order_relaxed));
-    if (waitQueue.compare_exchange_strong(
+    if (waitQueue.compare_exchange_weak(
         waitHead, waitingTask,
         /*success*/ std::memory_order_release,
         /*failure*/ std::memory_order_acquire)) {
@@ -1947,7 +1947,7 @@ void TaskGroupBase::waitAll(SwiftError* bodyError, AsyncTask *waitingTask,
       waitingTask->flagAsSuspendedOnTaskGroup(asAbstract(this));
     }
     // Put the waiting task at the beginning of the wait queue.
-    if (waitQueue.compare_exchange_strong(
+    if (waitQueue.compare_exchange_weak(
         waitHead, waitingTask,
         /*success*/ std::memory_order_release,
         /*failure*/ std::memory_order_acquire)) {