+ cxx_ver=m[0].str;
+ while(!cxx_ver.empty() && !FS::is_dir(FS::Path("/usr/include/c++")/cxx_ver))
+ {
+ string::size_type dot=cxx_ver.rfind('.');
+ if(dot==string::npos)
+ break;
+ cxx_ver.erase(dot);
+ }
+ if(verbose>=5)
+ IO::print("C++ version is %s\n", cxx_ver);