1. -dumpmachine
Print the compiler's target machine
2. -print-sysroot
Print the target sysroot directory that is used during compilation. (编译期间使用到的目录)
3. -print-libgcc-file-name(或-print-file-name)
获取libgcc.a文件的路径
4. -print-search-dirs
列出gcc搜索可配置的安装目录，程序和库目录清单时的路径