From da2ff102238e5d9ae4f634f89f6a1425ef99770d Mon Sep 17 00:00:00 2001
From: Dale Glass <dale@daleglass.net>
Date: Mon, 13 Apr 2026 20:03:25 +0200
Subject: [PATCH] Warn on null pointer in callback in Font.cpp

---
 libraries/render-utils/src/text/Font.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libraries/render-utils/src/text/Font.cpp b/libraries/render-utils/src/text/Font.cpp
index 6fcdffbfc21..710a3f63e1b 100644
--- a/libraries/render-utils/src/text/Font.cpp
+++ b/libraries/render-utils/src/text/Font.cpp
@@ -103,6 +103,11 @@ void Font::handleFontNetworkReply() {
 QThreadStorage<size_t> _readOffset;
 QThreadStorage<size_t> _readMax;
 int readHelper(void* dst, int length, void* data) {
+    if (!dst) {
+        qWarning() << "readHelper called with NULL pointer as first argument: dst = " << dst << "; length = " << length << "; data =" << data;
+        return 0;
+    }
+
     if (_readOffset.localData() + length > _readMax.localData()) {
         return -1;
     }