From 978264b08d09b6bd6b863f37811f5fb82740140d Mon Sep 17 00:00:00 2001
From: Benjamin Schwendinger <benjaminschwe@gmail.com>
Date: Mon, 2 Dec 2024 11:22:08 +0100
Subject: [PATCH] add UNPROTECT

---
 src/assign.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/assign.c b/src/assign.c
index 396f8e5b9..9fc12cabd 100644
--- a/src/assign.c
+++ b/src/assign.c
@@ -115,6 +115,7 @@ static int _selfrefok(SEXP x, Rboolean checkNames, Rboolean verbose) {
     //  Not being an extptr is for when users construct a data.table via structure() using dput, post
     //  a question, and find the extptr doesn't parse so put quotes around it (for example).
     //  In both cases the selfref is not ok.
+    UNPROTECT(1);
     return 0;
   }
   p = R_ExternalPtrAddr(v);