-Wpointer-sign -Wreorder -Wreturn-type -Wsequence-point
-Wsign-compare (only in C++) -Wstrict-aliasing -Wstrict-overflow=1
-Wswitch -Wtrigraphs -Wuninitialized (only with -O1 and above)
-Wunknown-pragmas -Wunused-function -Wunused-label -Wunused-value
-Wunused-variable
下列选项控制编译器警告信息:
例如 ：-Wstrict-prototypes使用了非原型的函数声明时给出警告
参考一下： GNU Makefile 使用手册 吧 。
