Bump to C++17

CI/before_script.osx.sh

@@ -13,7 +13,7 @@ cmake \
 -D CMAKE_PREFIX_PATH="$DEPENDENCIES_ROOT;$QT_PATH" \
 -D CMAKE_C_COMPILER_LAUNCHER="$CCACHE_EXECUTABLE" \
 -D CMAKE_CXX_COMPILER_LAUNCHER="$CCACHE_EXECUTABLE" \
--D CMAKE_CXX_FLAGS="-std=c++11 -stdlib=libc++" \
+-D CMAKE_CXX_FLAGS="-stdlib=libc++" \
 -D CMAKE_C_FLAGS_RELEASE="-g -O0" \
 -D CMAKE_CXX_FLAGS_RELEASE="-g -O0" \
 -D CMAKE_OSX_DEPLOYMENT_TARGET="10.12" \

CMakeLists.txt

@@ -416,7 +416,7 @@ endif()
 
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL GNU OR CMAKE_CXX_COMPILER_ID STREQUAL Clang)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Wundef -Wno-unused-parameter -std=c++14 -pedantic -Wno-long-long")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Wundef -Wno-unused-parameter -std=c++17 -pedantic -Wno-long-long")
     add_definitions( -DBOOST_NO_CXX11_SCOPED_ENUMS=ON )
 
     if (APPLE)