diff --git a/src/V3SchedVirtIface.cpp b/src/V3SchedVirtIface.cpp
index cbd0c9fc3..2a4b4a435 100644
--- a/src/V3SchedVirtIface.cpp
+++ b/src/V3SchedVirtIface.cpp
@@ -42,6 +42,7 @@ class VirtIfaceVisitor final : public VNVisitor {
 private:
     // NODE STATE
     // AstIface::user1() -> AstVarScope*. Trigger var for this interface
+    // AstVar::user1() -> AstIface*. Interface under which variable is
     const VNUser1InUse m_user1InUse;
 
     // TYPES
@@ -149,10 +150,7 @@ private:
             memberVarp = nodep->varp();
         } else if (VN_IS(nodep->backp(), AssignW)) {
             memberVarp = nodep->varScopep()->varp();
-            AstNode* backp = memberVarp;
-            while ((backp = backp->backp())) {
-                if ((ifacep = VN_CAST(backp, Iface))) break;
-            }
+            ifacep = VN_CAST(memberVarp->backp(), Iface);
         }
 
         if (ifacep && memberVarp) {
@@ -168,6 +166,11 @@ public:
     // CONSTRUCTORS
     explicit VirtIfaceVisitor(AstNetlist* nodep)
         : m_netlistp{nodep} {
+        nodep->foreach([](AstIface* const ifacep) {
+            for (AstNode* nodep = ifacep->stmtsp(); nodep; nodep = nodep->nextp()) {
+                if (AstVar* const varp = VN_CAST(nodep, Var)) varp->user1p(ifacep);
+            }
+        });
         iterate(nodep);
     }
     ~VirtIfaceVisitor() override = default;