diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2450d0016f..f71c9e98bb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,6 +24,7 @@ project(OpenMW)
 
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
 
 include(GNUInstallDirs)