From d638508d332958c618264c432e71138f44f81794 Mon Sep 17 00:00:00 2001
From: Andy Maloney <asmaloney@gmail.com>
Date: Tue, 10 Sep 2019 10:51:13 -0400
Subject: [PATCH] Set C++ standard options in CMake per-target instead of
 globally (#735)

Setting CMAKE_CXX_STANDARD and CMAKE_CXX_STANDARD_REQUIRED directly is problematic when including yaml-cpp as a subproject.

The proper way is to set these per-target.
---
 CMakeLists.txt      |  9 +++++----
 test/CMakeLists.txt |  5 +++++
 util/CMakeLists.txt | 12 ++++++++++++
 3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 60bff7e..03848bb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,10 +26,6 @@ option(YAML_CPP_INSTALL "Enable generation of install target" 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)
 
@@ -261,6 +257,11 @@ if (NOT CMAKE_VERSION VERSION_LESS 2.8.12)
         PRIVATE $<BUILD_INTERFACE:${YAML_CPP_SOURCE_DIR}/src>)
 endif()
 
+set_target_properties(yaml-cpp PROPERTIES
+    CXX_STANDARD 11
+    CXX_STANDARD_REQUIRED ON
+)
+
 set_target_properties(yaml-cpp PROPERTIES
   COMPILE_FLAGS "${yaml_c_flags} ${yaml_cxx_flags}"
 )
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 8bdf303..0a669d5 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -51,6 +51,11 @@ add_executable(run-tests
     ${test_headers}
 )
 
+set_target_properties(run-tests PROPERTIES
+    CXX_STANDARD 11
+    CXX_STANDARD_REQUIRED ON
+)
+
 add_dependencies(run-tests googletest_project)
 
 set_target_properties(run-tests PROPERTIES
diff --git a/util/CMakeLists.txt b/util/CMakeLists.txt
index 8a803b0..09dafa2 100644
--- a/util/CMakeLists.txt
+++ b/util/CMakeLists.txt
@@ -2,13 +2,25 @@ cmake_minimum_required(VERSION 3.5)
 
 add_sources(parse.cpp)
 add_executable(parse parse.cpp)
+set_target_properties(parse PROPERTIES
+    CXX_STANDARD 11
+    CXX_STANDARD_REQUIRED ON
+)
 target_link_libraries(parse yaml-cpp)
 
 add_sources(sandbox.cpp)
 add_executable(sandbox sandbox.cpp)
+set_target_properties(sandbox PROPERTIES
+    CXX_STANDARD 11
+    CXX_STANDARD_REQUIRED ON
+)
 target_link_libraries(sandbox yaml-cpp)
 
 add_sources(read.cpp)
 add_executable(read read.cpp)
+set_target_properties(read PROPERTIES
+    CXX_STANDARD 11
+    CXX_STANDARD_REQUIRED ON
+)
 target_link_libraries(read yaml-cpp)