Set standard as cache variable

CMakeLists.txt

@@ -8,8 +8,9 @@ set(
 	FILEPATH
 	"Default toolchain"
 	)
-set(CMAKE_CXX_STANDARD 17)
-set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 17 CACHE STRING "C++ standard")
+set(CMAKE_CXX_STANDARD_REQUIRED ON CACHE BOOL "Require C++ standard to be supported")
+set(CMAKE_POSITION_INDEPENDENT_CODE ON CACHE BOOL "compile as PIC by default")
 
 option(HUNTER_ENABLED "Enable Hunter package manager" OFF)
 include("cmake/HunterGate.cmake")