when set CMAKE_TOOLCHAIN_FILE, can't find include paths.

I want use Clion for embedded development.

When I set CMAKE_TOOLCHAIN_FILE, CMakeCache and build is correct, but the IDE can't find the header cearch path, editor's autocomplete doesn't work for include_directories.

And I have compared the generated CMakeModel file, the one with CMAKE_TOOLCHAIN_FILE has smller size and stoped at:

The host system is: Windows - 6.2 - AMD64

The target system is: mbedOS - 1 - armv7-m

Maybe this is the key.