Add checks for useful c++1y features

CMakeLists.txt

@@ -52,6 +52,19 @@ IF(SDL2PP_WITH_WERROR)
 	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WERROR_FLAG}")
 ENDIF(SDL2PP_WITH_WERROR)
 
+# platform checks
+INCLUDE(CheckCompile)
+CHECK_COMPILE(
+	SDL2PP_WITH_EXPERIMENTAL_OPTIONAL
+	${PROJECT_SOURCE_DIR}/cmake/std_experimental_optional_test.cc
+	"Checking for experimental/optional header"
+)
+CHECK_COMPILE(
+	SDL2PP_WITH_DEPRECATED
+	${PROJECT_SOURCE_DIR}/cmake/attribute_deprecated_test.cc
+	"Checking for [[deprecated]] attribute"
+)
+
 # config.h
 CONFIGURE_FILE(
 	SDL2pp/Config.hh.in

SDL2pp/Config.hh.in

@@ -30,5 +30,7 @@
 
 #cmakedefine SDL2PP_WITH_IMAGE
 #cmakedefine SDL2PP_WITH_2_0_4
+#cmakedefine SDL2PP_WITH_EXPERIMENTAL_OPTIONAL
+#cmakedefine SDL2PP_WITH_DEPRECATED
 
 #endif

cmake/CheckCompile.cmake

@@ -0,0 +1,11 @@
+MACRO(CHECK_COMPILE RESULT_VAR SOURCE_FILE DESCRIPTION)
+	SET(SAVED_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
+	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WERROR_FLAG}")
+	TRY_COMPILE(${RESULT_VAR} ${CMAKE_BINARY_DIR} ${SOURCE_FILE})
+	IF(${RESULT_VAR})
+		MESSAGE(STATUS "${DESCRIPTION}: yes")
+	ELSE(${RESULT_VAR})
+		MESSAGE(STATUS "${DESCRIPTION}: no")
+	ENDIF(${RESULT_VAR})
+	SET(CMAKE_CXX_FLAGS "${SAVED_CXX_FLAGS}")
+ENDMACRO(CHECK_COMPILE)

cmake/attribute_deprecated_test.cc

@@ -0,0 +1,7 @@
+[[deprecated]]
+void f() {
+}
+
+int main() {
+	return 0;
+}

cmake/std_experimental_optional_test.cc

@@ -0,0 +1,8 @@
+#include <experimental/optional>
+#include <string>
+
+int main() {
+	std::experimental::optional<std::string> o;
+
+	return !o;
+}