diff --git a/src/V3Assert.cpp b/src/V3Assert.cpp
index 87cd14f5b..2adda9d22 100644
--- a/src/V3Assert.cpp
+++ b/src/V3Assert.cpp
@@ -709,9 +709,8 @@ class AssertVisitor final : public VNVisitor {
         }
         VL_DO_DANGLING(pushDeletep(nodep), nodep);
     }
-    void visit(AstVarRef* nodep) override {
-        iterateChildren(nodep);
-        if (m_inSampled && !(nodep->varp() && nodep->varp()->noSample())) {
+    void visit(AstNodeVarRef* nodep) override {
+        if (m_inSampled && !nodep->varp()->noSample()) {
             if (!nodep->access().isReadOnly()) {
                 nodep->v3warn(E_UNSUPPORTED,
                               "Unsupported: Write to variable in sampled expression");