Fix the error message for "missing separator"
diff --git a/eval.go b/eval.go
index 11e376b..dbff80f 100644
--- a/eval.go
+++ b/eval.go
@@ -161,7 +161,7 @@
 	result := ev.evalExpr(ast.expr)
 	if result != "" {
 		// TODO: Fix rule_in_var.mk.
-		fmt.Printf("%s:%d: *** missing separator.  Stop.\n", ast.filename, ast.lineno)
+		Error(ast.filename, ast.lineno, "*** missing separator.")
 	}
 }