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问 /**********测试代码*********************/  
#define CHANGE 1

unsigned char i;

#if CHANGE
  void dump(void)
  {
    if(i>0) i++;
  }
#endif

void test(void*p)
{
    i=1;
    p=p;

}

unsigned char argu_test(void (*ppdata)(void*pp),unsigned char m)
{
    unsigned int p,t;
    t=(unsigned int)(*ppdata);
    p=(unsigned int)ppdata;
    return ++m;
}

void main(void)
{
    unsigned char j=0;
    while(1)
    {
         if(argu_test(test,3)) continue;
        j++;
    }
}

很显然，改变CHANGE的宏定义就可以改变test函数的首地止
我得测试结果

   编译器             CHANGE的值           p值        t值
  Turbo C 2.0             1                522        522
                          0                506        506
  KeilC  7.01             1                0x3c       0x3c
                          0                0x32       0x32
  ICCAVR 6.28             1                0x54       0x54
                          0                0x54       0x54

从反汇编来看，KeilC里的值和其地址值是对应的，TurboC没看，ICC中的值和其首地址明显不对应（无论首地址是多少，p、t值都是常量0x0054）！
  请大虾们用自己的ICC测试一下，看看是不是只是我的编译器有问题，谢谢！


答 1: 没人有ICC吗？把程序复制进去运行一下好像不麻烦吧？ 答 2: ICCAVR BUG? 答 3: ICCAVR BUG?CHANGE=1,test=0x38, CHANGE=0,test=0x2e,使用AVR STUDIO3.56用模拟运行方式查看. 答 4: zhaohuoc兄：你查看的是test的值！
这个值是正确的
我说的是在函数调用时，这个值不会被正确的传递！◎

不信老兄再运行一次，看看 p的值和 t 的值！ 答 5: 我发信给imagecraft,问题解决了但不理解为什么他们要把编译器做成这样。TC是直接传送地址的。不知道到底TC和标准C兼容还是ICC.

When you pass an address of a function, ICCAVR creates a word in the
flash
that CONTAINS the address of the function, and uses the address of that
label as the value, e.g.

_PF_test::
         .word   `_test

         ...
In C, when you say
         void test();
         ...

         argu_test(test,...

instead of passing address of test, we would pass the address the of
PF_test. It all works right because when you call a function pointer,
the
compiler does the indirect fetching for you, so it works right.



答 6: 音乐乐乐 你试试下面这一段，
unsigned char argu_test(void (*ppdata)(void*pp),unsigned char m)
{
    unsigned int p,t;
    t=(unsigned int)(*(unsigned char *)ppdata);
    p=(unsigned int)ppdata;
    return ++m;
}

按照你的代码，AVRSTUDIO算出的P=T，P一段的代码干脆给优化了，好象并没有把ppdata当做指针，我还是不明白你这段代码到底想说明写什么 答 7: 我想说明再其他编译器传递的是函数首地址而ICC传递的是一个指向函数首地址的指针 答 8: 明白ICC传递的是一个指向函数首地址的指针的指针

感谢分享