How to use >C++11 with a ignition or gazebo project

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If I am compiling against ign-*, or gazebo, I get -std=c++11 added to my CMAKE_CXX_FLAGS. Now, I understand that ign-* and gazebo require C++11, but I want to use C++14 or C++17.

For example, target_link_library(target ${IGNITION-TRANSPORT-LIBRARIES) will add -std=c++11 to the very end of my compile flags rendering any attempts like set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++1z useless.