Use optional for type-safe retval

include/serializedAsynchronousContinuation.h

@@ -7,6 +7,7 @@
 #include <atomic>
 #include <chrono>
 #include <iostream>
+#include <optional>
 #include <componentThread.h>
 #include <lockSet.h>
 #include <asynchronousContinuation.h>
@@ -79,9 +80,12 @@ public:
 		invocationTarget(std::move(invocationTarget))
 		{
 #ifdef CONFIG_ENABLE_DEBUG_LOCKS
-			if (traceContinuationHistoryForDeadlock())
+			std::optional<std::reference_wrapper<Qutex>> firstFailedQutex =
+				traceContinuationHistoryForDeadlock();
+
+			if (firstFailedQutex.has_value())
 			{
-				handleDeadlock();
+				handleDeadlock(firstFailedQutex.value().get());
 				throw std::runtime_error(
 					"LockerAndInvoker::LockerAndInvoker(): Deadlock detected");
 			}
@@ -308,7 +312,8 @@ public:
 		};
 
 		bool traceContinuationHistoryForDeadlockOn(Qutex &firstFailedQutex);
-		bool traceContinuationHistoryForDeadlock(void)
+		std::optional<std::reference_wrapper<Qutex>>
+		traceContinuationHistoryForDeadlock(void)
 		{
 			for (auto& lockUsageDesc
 				: serializedContinuation.requiredLocks.locks)
@@ -316,10 +321,10 @@ public:
 				if (traceContinuationHistoryForDeadlockOn(
 					lockUsageDesc.first.get()))
 				{
-					return true;
+					return std::ref(lockUsageDesc.first.get());
 				}
 			}
-			return false;
+			return std::nullopt;
 		}
 
 		/**