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Author: Catfish-Man

include/swift/ABI/TaskStatus.h

@@ -176,7 +176,9 @@ class TaskGroupTaskStatusRecord : public TaskStatusRecord {
   TaskGroupTaskStatusRecord(AsyncTask *child)
       : TaskStatusRecord(TaskStatusRecordKind::TaskGroup),
         FirstChild(child),
-        LastChild(child) {}
+        LastChild(child) {
+    assert(!LastChild || !LastChild->childFragment()->getNextChild());
+  }
 
   TaskGroup *getGroup() { return reinterpret_cast<TaskGroup *>(this); }