diff --git a/src/Expr.h b/src/Expr.h
index b92ae708c8..656933ce81 100644
--- a/src/Expr.h
+++ b/src/Expr.h
@@ -1153,6 +1153,9 @@ public:
 	// Optimization-related:
 	ExprPtr Duplicate() override;
 
+	bool IsReduced(Reducer* c) const override;
+	ExprPtr Reduce(Reducer* c, StmtPtr& red_stmt) override;
+
 protected:
 	ValPtr Fold(Val* v) const override;
 
diff --git a/src/script_opt/Expr.cc b/src/script_opt/Expr.cc
index dbf40a1991..c9679838a4 100644
--- a/src/script_opt/Expr.cc
+++ b/src/script_opt/Expr.cc
@@ -1917,6 +1917,22 @@ ExprPtr HasFieldExpr::Duplicate()
 	return SetSucc(new HasFieldExpr(op->Duplicate(), util::copy_string(field_name)));
 	}
 
+bool HasFieldExpr::IsReduced(Reducer* c) const
+	{
+	return op->GetType<RecordType>()->FieldHasAttr(field, ATTR_OPTIONAL);
+	}
+
+ExprPtr HasFieldExpr::Reduce(Reducer* c, StmtPtr& red_stmt)
+	{
+	if ( ! op->GetType<RecordType>()->FieldHasAttr(field, ATTR_OPTIONAL) )
+		{
+		auto true_constant = make_intrusive<ConstExpr>(val_mgr->True());
+		return TransformMe(true_constant, c, red_stmt);
+		}
+
+	return UnaryExpr::Reduce(c, red_stmt);
+	}
+
 ExprPtr RecordConstructorExpr::Duplicate()
 	{
 	auto op_l = op->Duplicate()->AsListExprPtr();