带返回值宏函数[C语言]

#include 
 
#define compute(x, y, n)\                                                       
({\                                                                             
        int sum_tmp = 0;\                                                       
        for (int i = 0; i < n; ++i)\                                            
                sum_tmp += x[i] * y[i];\                                        
        sum_tmp;\                                                               
})                                                                              
                                                                                
                                                                                
int dotProduct(int x[], int y[], int n)                                         
{                                                                               
        int i, sum;                                                             
                                                                                
        sum = compute(x, y, n);                                                 
                                                                                
        return sum;                                                             
}                                                                               
                                                                                
int main(void)                                                                  
{                                                                               
        int x[] = {1, 2};                                                       
        int y[] = {3, 4};                                                       
                                                                                
        int result = dotProduct(x, y, 2);                                       
                                                                                
        printf("%d\n", result);                                                 
                                                                                
        return 0;                                                               
}