util.c:315
static void
push_element(const char *path, VALUE vinfo)
{
    struct PathList *p;
    struct PathInfo *info = (struct PathInfo *)vinfo;

    p = ALLOC(struct PathList);
    MEMZERO(p, struct PathList, 1);
    p->path = ruby_strdup(path);
    p->next = info->head;
    info->head = p;
    info->count++;
}
