StanfordSwap vs EvineSwap

#include <stdio.h>
#include <string.h>

void StanfordSwap(void *vp1, void *vp2, int size)
{
    char buffer[size];
    memcpy(buffer,vp1,size);
    memcpy(vp1,vp2,size);
    memcpy(vp2,buffer,size);
}

#define EvineSwap(thing1,thing2,Type)       \
    {                                       \
        Type temp = thing1;                 \
        thing1 = thing2;                    \
        thing2 = temp;                      \
    }


#define EvineOtherSwap_Define(Type)                         \
    void EvineOtherSwap_##Type(Type *thing1, Type *thing2)  \
    {                                                       \
        Type temp = *thing1;                                \
        *thing1 = *thing2;                                  \
        *thing2 = temp;                                     \
    }
    
EvineOtherSwap_Define(int)
EvineOtherSwap_Define(char)


int main() {
    int apple = 4;
    int pear = 70;
    
    EvineOtherSwap_int(&apple,&pear);
    //EvineSwap(apple,pear,int);
    
    //StanfordSwap(&apple,&pear,sizeof(int));
    
    printf("apple: %i\n",apple);
    printf("pear: %i\n",pear);
    return 0;
}