main.c(3): warning: no previous prototype for function 'SystemInit' [-Wmissing-prototypes]
void SystemInit ( void ) //为<C1><CB>骗<B1><E0><D2><EB><C6><F7><B5><C4>
没在头文件里面声明吗?头文件加上声明看下。或者看下这个https://blog.csdn.net/yaoyaohyl/article/details/113133290