Due to the commit of f13cb20ed19c41b9ff85ef1c9ec0883a21d1d5bf, the environment file doesn't need to include the c++ include path int the CXXFLAGS.
Need to remove it from meta-environment.
fixed in commit f5a1f1d.
http://git.pokylinux.org/cgit/cgit.cgi/poky/commit/?id=d38ad3271829b2d282c973e69edd265ef52174c8
Verified that the c++ include path is removed in commit f5a1f1d.