How to use c++98 without gnu extensions in cmake >= 2.6?

Question

I have to support cmake 2.6 at least (and latest versions like 3.12 too):

cmake_minimum_required(VERSION 2.6)

And want to specify the old c++ standard (c++98) and forbid gnu extensions (use -std=c++98 instead of -std=gnu++98). In newer versions (since 3.0) we have CXX_EXTENSIONS and CXX_STANDARD , but I can't use them because cmake 2.6 doesn't support them.

I tried to specify add_definitions(-std=c++98) , but it causes compile string like this:

/usr/bin/c++ ..... -std=c++98 ..... -std=gnu++98 .....

Answer 1

您始终可以将CMAKE_CXX_FLAGS设置（或修改）为-std=c++98以否决CMake自己设置的内容。