From 4b1054e1aaa97d7e7da62bb0e96c49d1736a9c9e Mon Sep 17 00:00:00 2001
From: "Azamat H. Hackimov" <azamat.hackimov@gmail.com>
Date: Tue, 27 Feb 2018 10:42:48 +0500
Subject: [PATCH] Added CMake's checks for C++11 standards

Raised minimal version of CMake to 3.1, since on old systems there no
decent compilers that supports c++11.

Closes #377.
---
 CMakeLists.txt      | 9 ++++++---
 test/CMakeLists.txt | 6 ------
 util/CMakeLists.txt | 4 +---
 3 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index f821a91..059ce9e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,9 +1,8 @@
 ###
 ### CMake settings
 ###
-## Due to Mac OSX we need to keep compatibility with CMake 2.6
 # see http://www.cmake.org/Wiki/CMake_Policies
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 3.1)
 # see http://www.cmake.org/cmake/help/cmake-2-8-docs.html#policy:CMP0012
 if(POLICY CMP0012)
 	cmake_policy(SET CMP0012 OLD)
@@ -46,6 +45,10 @@ option(YAML_CPP_BUILD_CONTRIB "Enable contrib stuff in library" ON)
 #     http://www.cmake.org/cmake/help/cmake2.6docs.html#command:add_library
 option(BUILD_SHARED_LIBS "Build Shared Libraries" OFF)
 
+# Set minimum C++ to 2011 standards
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
 # --> Apple
 option(APPLE_UNIVERSAL_BIN "Apple: Build universal binary" OFF)
 
@@ -185,7 +188,7 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "GNU" OR
 		set(GCC_EXTRA_OPTIONS "${GCC_EXTRA_OPTIONS} ${FLAG_TESTED}")
 	endif()
 	#
-	set(yaml_cxx_flags "-Wall ${GCC_EXTRA_OPTIONS} -pedantic -Wno-long-long -std=c++11 ${yaml_cxx_flags}")
+	set(yaml_cxx_flags "-Wall ${GCC_EXTRA_OPTIONS} -pedantic -Wno-long-long ${yaml_cxx_flags}")
 
 	### Make specific
 	if(${CMAKE_BUILD_TOOL} MATCHES make OR ${CMAKE_BUILD_TOOL} MATCHES gmake)
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 3633da5..d24a05f 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -15,12 +15,6 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "GNU" OR
   if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     set(yaml_test_flags "${yaml_test_flags} -Wno-c99-extensions")
   endif()
-
-  if(CMAKE_COMPILER_IS_GNUCXX)
-    set(yaml_test_flags "${yaml_test_flags} -std=gnu++11")
-  else()
-    set(yaml_test_flags "${yaml_test_flags} -std=c++11")
-  endif()
 endif()
 
 file(GLOB test_headers [a-z_]*.h)
diff --git a/util/CMakeLists.txt b/util/CMakeLists.txt
index 2286627..6777686 100644
--- a/util/CMakeLists.txt
+++ b/util/CMakeLists.txt
@@ -1,14 +1,12 @@
 add_sources(parse.cpp)
 add_executable(parse parse.cpp)
 target_link_libraries(parse yaml-cpp)
-set_target_properties(parse PROPERTIES COMPILE_FLAGS "-std=c++11")
 
 add_sources(sandbox.cpp)
 add_executable(sandbox sandbox.cpp)
 target_link_libraries(sandbox yaml-cpp)
-set_target_properties(sandbox PROPERTIES COMPILE_FLAGS "-std=c++11")
 
 add_sources(read.cpp)
 add_executable(read read.cpp)
 target_link_libraries(read yaml-cpp)
-set_target_properties(read PROPERTIES COMPILE_FLAGS "-std=c++11")
+