diff --git a/os/hal/osal/nil/osal.h b/os/hal/osal/nil/osal.h
index 77afc18eb..37838cc88 100644
--- a/os/hal/osal/nil/osal.h
+++ b/os/hal/osal/nil/osal.h
@@ -731,6 +731,8 @@ static inline msg_t osalThreadEnqueueTimeoutS(threads_queue_t *tqp,
  */
 static inline void osalEventObjectInit(event_source_t *esp) {
 
+  osalDbgCheck(esp != NULL);
+
   esp->flags = 0;
   esp->cb    = NULL;
   esp->param = NULL;
@@ -747,6 +749,8 @@ static inline void osalEventObjectInit(event_source_t *esp) {
 static inline void osalEventBroadcastFlagsI(event_source_t *esp,
                                             eventflags_t flags) {
 
+  osalDbgCheck(esp != NULL);
+
   esp->flags |= flags;
   if (esp->cb != NULL)
     esp->cb(esp);
@@ -763,12 +767,37 @@ static inline void osalEventBroadcastFlagsI(event_source_t *esp,
 static inline void osalEventBroadcastFlags(event_source_t *esp,
                                            eventflags_t flags) {
 
+  osalDbgCheck(esp != NULL);
+
   chSysLock();
   osalEventBroadcastFlagsI(esp, flags);
   chSchRescheduleS();
   chSysUnlock();
 }
 
+/**
+ * @brief   Event callback setup.
+ * @note    The callback is invoked from ISR context and can
+ *          only invoke I-Class functions. The callback is meant
+ *          to wakeup the task that will handle the event by
+ *          calling @p osalEventGetAndClearFlagsI().
+ *
+ * @param[in] esp       pointer to the event flags object
+ * @param[in] cb        pointer to the callback function
+ * @param[in] param     parameter to be passed to the callback function
+ *
+ * @api
+ */
+static inline void osalEventSetCallback(event_source_t *esp,
+                                        eventcallback_t cb,
+                                        void *param) {
+
+  osalDbgCheck(esp != NULL);
+
+  esp->cb    = cb;
+  esp->param = param;
+}
+
 /**
  * @brief   Initializes s @p mutex_t object.
  *
diff --git a/os/nil/include/nil.h b/os/nil/include/nil.h
index f815b2153..109f99533 100644
--- a/os/nil/include/nil.h
+++ b/os/nil/include/nil.h
@@ -391,8 +391,10 @@ typedef struct {
    * @brief   Panic message.
    * @note    This field is only present if some debug options have been
    *          activated.
+   * @note    Accesses to this pointer must never be optimized out so the
+   *          field itself is declared volatile.
    */
-  const char            *dbg_panic_msg;
+  const char            * volatile dbg_panic_msg;
 #endif
 } nil_system_t;