Keil报错:declaration may not appear after executable statement in block.

错误提示：declaration may not appear after executable statement in block.

错误举例：

int main()
{
   int a=0; //声明变量a
   a=1; //给变量a赋值
   int b=0; //声明变量b并赋值，此处报错。因为b的声明在执行语句“a=1”之后。应该把声明放在函数开头位置
   while(1)
   {
   }
}

解决办法1：

int main()
{
   int a=0; //声明变量a
   int b=0; //声明变量b并赋值

   a=1; //给变量a赋值

   while(1)
   {
   }
}

解决办法2：keil中把c/c++的C99 Mode勾上即可