ref: ec4c79f3a6ed97ec0c407a870827382cbefb1166
dir: /src/libc/string/memcpy.c/
#include <string.h>
#undef memcpy
void *
memcpy(void *restrict s1, const void *restrict s2, size_t n)
{
	char *d = s1;
	const char *s = s2;
	while (n-- > 0)
		*d++ = *s++;
	return s1;
}