ref: 647f85d6fac7e0aee9881909cd5086941e3d11c7
dir: /lib/c/src/memcpy.c/
#include <string.h>
#undef memcpy
void *
memcpy(void * restrict dst, const void * restrict src, size_t n)
{
char *s1 = dst;
const char *s2 = src;
while (n-- > 0)
*s1++ = *s2++;
return dst;
}