From 4ff53269f024e7bd4b5b0958d6dd3dfc3dce685c Mon Sep 17 00:00:00 2001
From: Aoran Zeng <ccmywish@qq.com>
Date: Sat, 9 Aug 2025 19:38:14 +0800
Subject: [PATCH] Warn when` xy_strdup()` called with NULL

---
 lib/xy.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/xy.h b/lib/xy.h
index d44bc3b..c08f66b 100644
--- a/lib/xy.h
+++ b/lib/xy.h
@@ -287,6 +287,12 @@ xy_strjoin (unsigned int count, ...)
 static char *
 xy_strdup (const char *str)
 {
+  if (!str)
+    {
+      fprintf (stderr, "xy.h: xy_strdup() called with NULL!");
+      return NULL;
+    }
+
   size_t len = strlen (str);
   char *new = xy_malloc0 (len + 1);
   strcpy (new, str);