core: Move Time::StaticInit call to helper constructor

src/core/model/nstime.h

@@ -840,13 +840,6 @@ typedef void (*Time)(Time oldValue, Time newValue);
 
 } // namespace TracedValueCallback
 
-/**
- * Force static initialization order of Time in each compilation unit.
- * This is internal to the Time implementation.
- * \relates Time
- */
-static bool g_TimeStaticInit [[maybe_unused]] = Time::StaticInit();
-
 /**
  * Equality operator for Time.
  * \param [in] lhs The first value
@@ -1490,6 +1483,27 @@ class TimeWithUnit
  */
 TYPENAMEGET_DEFINE(Time);
 
+/**
+ * \ingroup time
+ *
+ * \brief Helper class to force static initialization
+ * of Time in each compilation unit, ensuring it is
+ * initialized before usage.
+ * This is internal to the Time implementation.
+ * \relates Time
+ */
+class TimeInitializationHelper
+{
+  public:
+    /** Default constructor calls Time::StaticInit */
+    TimeInitializationHelper()
+    {
+        Time::StaticInit();
+    }
+};
+
+static TimeInitializationHelper g_timeInitHelper; ///< Instance of Time static initialization helper
+
 } // namespace ns3
 
 #endif /* TIME_H */