diff --git a/Source/CMakeLists.txt b/Source/CMakeLists.txt
index b5a92a5c1b..71ed5876c5 100644
--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -20,12 +20,9 @@ else()
   # CMAKE_CXX_STANDARD cannot be used here because we require C++14 or newer, not any standard.
   check_and_add_flag(CXX17 -std=c++17)
   if(NOT FLAG_CXX_CXX17)
-    check_and_add_flag(CXX1Z -std=c++1z)
-    if (NOT FLAG_CXX_CXX1Z)
-      set(CMAKE_CXX_STANDARD 14)
-      set(CMAKE_CXX_STANDARD_REQUIRED ON)
-      set(CMAKE_CXX_EXTENSIONS OFF)
-    endif()
+    set(CMAKE_CXX_STANDARD 14)
+    set(CMAKE_CXX_STANDARD_REQUIRED ON)
+    set(CMAKE_CXX_EXTENSIONS OFF)
   endif()
 
   # These compat headers must not be in the include path when building with MSVC,