海湾合作委员会:建议围绕比较括号的括号不能自己解决

Question

我试图检查这是否等于零

//Address already malloc

void MyCheck (void *Address){

    if ( (long)Address & (~(sizeof(long)-1)) != 0 ){
           printf("Invalid");
    }

}

当试图编译它给我:

Error:  suggest parentheses around comparison in operand 
         of '&' [-Werror=parentheses]

Answer 1

!=优先级高于&,所以你的代码实际上是这样的:

if ((long)Address &  ( (~(sizeof(long)-1)) != 0 ) )
                     ^                          ^

gcc建议这可能是一个错误,它可能是.你想要:

if ( ( (long)Address &  (~(sizeof(long)-1)) ) != 0 )
     ^                                      ^