Fix false positive -Wstringop-overread warning in GCC

Author: odygrd

CHANGELOG.md

@@ -93,6 +93,7 @@
 - Add support for `void*` formatting ([#759](https://github.com/odygrd/quill/issues/759))
 - Fix a bug in `RotatingJsonFileSink.h` where file size-based rotation wasn't triggering
   properly ([#767](https://github.com/odygrd/quill/issues/767))
+- Fix false positive `-Wstringop-overread` warning in GCC ([#766](https://github.com/odygrd/quill/issues/766))
 
 ## v9.0.2
 

include/quill/core/Codec.h

@@ -94,7 +94,20 @@ QUILL_NODISCARD inline size_t safe_strnlen(char const* str, size_t maxlen) noexc
     return 0;
   }
 
+#if defined(__GNUC__) && !defined(__clang__)
+  // Suppress false positive in GCC - memchr safely stops at null terminator
+  #pragma GCC diagnostic push
+  #if __GNUC__ >= 13
+    #pragma GCC diagnostic ignored "-Wstringop-overread"
+  #endif
+#endif
+
   auto end = static_cast<char const*>(std::memchr(str, '\0', maxlen));
+
+#if defined(__GNUC__) && !defined(__clang__)
+  #pragma GCC diagnostic pop
+#endif
+
   return end ? static_cast<size_t>(end - str) : maxlen;
 }