diff --git a/ets2panda/checker/types/ets/etsFunctionType.cpp b/ets2panda/checker/types/ets/etsFunctionType.cpp
index 0ec3b4ecaca3259907143dc8f1e7358d05407ff4..3a333a507e371406e58a9798e0d446d5511e50de 100644
--- a/ets2panda/checker/types/ets/etsFunctionType.cpp
+++ b/ets2panda/checker/types/ets/etsFunctionType.cpp
@@ -209,6 +209,9 @@ static bool SignatureIsSupertypeOf(TypeRelation *relation, Signature *super, Sig
     if (super->MinArgCount() < sub->MinArgCount()) {
         return false;
     }
+    if (super->MinArgCount() == sub->MinArgCount() && super->Params().size() != sub->Params().size()) {
+        return false;
+    }
     if ((super->RestVar() != nullptr && sub->RestVar() == nullptr) ||
         (super->RestVar() == nullptr && sub->RestVar() != nullptr)) {
         return false;