VPRINTF
VPRINTF("F %u\n", i);
VPRINTF("A %d\n", j);
VPRINTF("F %u\n", i);
VPRINTF("A %d\n", j);
VPRINTF("alloc_unr_specific failed %d %d\n", x, v);
VPRINTF("alloc_unr_specific failed %d %d\n", x,
VPRINTF("iter %d: iter %d != val %d\n", i, v, vals[i]);
VPRINTF("iter %d: val %d\n", i, v);