action: allow fence ModelActions to have location == NULL

diff --git a/action.cc b/action.cc
index 9427c7d204e4a8e3a509f7cda437c7c67439e58f..402ff5064ace78cc8e2076aa7254e905063fc3bc 100644 (file)
--- a/action.cc
+++ b/action.cc
@@ -37,7 +37,7 @@ ModelAction::ModelAction(action_type_t type, memory_order order, void *loc,
        sleep_flag(false)
 {
        /* References to NULL atomic variables can end up here */
-       ASSERT(loc || type == MODEL_FIXUP_RELSEQ);
+       ASSERT(loc || type == ATOMIC_FENCE || type == MODEL_FIXUP_RELSEQ);
 
        Thread *t = thread ? thread : thread_current();
        this->tid = t->get_id();