suppress pointless warning for Ninja

CMakeLists.txt

@@ -2,6 +2,11 @@
 
 cmake_minimum_required(VERSION 2.8.12)
 
+if (POLICY CMP0058)
+	# Ninja requires custom command byproducts to be explicit
+	cmake_policy(SET CMP0058 NEW)
+endif()
+
 project (CotireExample)
 
 set (CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/CMake")