C/C++:"for"宏来跟踪运行多次迭代的循环

Question

我尝试使用下面的代码来跟踪使用新变量的各个循环的迭代ForloopCountM.该代码适用于循环内的循环和循环循环.但是Macro在以下两种情况下都失败了,我需要帮助如何解决这个问题并跟踪迭代次数.

void    forloopTrace(int ForloopCount)
{
    if( ForloopCount==50)
    printf("Invalid \n");
}

#define CONCAT_IMPL( x, y ) x##y
#define MACRO_CONCAT( x, y ) CONCAT_IMPL( x, y )

#define FORlOOPCOUNTM MACRO_CONCAT(ForloopCountM,__LINE__)

#define for(args...)\
    int FORlOOPCOUNTM=0;\
for(args,FORlOOPCOUNTM++,forloopTrace(FORlOOPCOUNTM))\

int main()
{
    int i,j,x,y;
    j=100;
    y=200;
    for(i=0;i<j;i)   //works fine
    {
        i++;
        for(x=0;x<y;x) //works fine
            x++;
    }
    if(i>0)
       for(;i>0;)    //ERROR
         i--;
    for(;;)   //Error
    {
        i++;
    }

    return 0;
}

Answer 1

您可以添加__LINE__ 预定义的宏来声明您的ForloopCountM

#define CONCAT_IMPL( x, y ) x##y
#define MACRO_CONCAT( x, y ) CONCAT_IMPL( x, y )

#define FORlOOPCOUNTM MACRO_CONCAT(ForloopCountM,__LINE__)

#define for(args...)\
int FORlOOPCOUNTM=0;\
for(args,FORlOOPCOUNTM++)\
    if(FORlOOPCOUNTM==50)\
        printf("\n For loop is running more than 50 iterations !! \n");\
    else

int main()
{
    int i,j,x,y;
    j=100;
    y=200;
    for(i=0;i<j;i)   //works fine
    {
        i++;
        for(x=0;x<y;x) //works fine
            x++;
    }
    for(i=0;i<y;i)   //works fine too :)
    {
        i++;
    }
    return 0;
}

http://ideone.com/kvQ09r

编辑:感谢user3956566我添加了一个关于预定义宏的gcc页面的链接