/* May as well allocate all the spaces at once: it saves us from
* having to decide what to do if only some of the allocations
* succeed. SPACES must be page-aligned, since the GC expects the
/* May as well allocate all the spaces at once: it saves us from
* having to decide what to do if only some of the allocations
* succeed. SPACES must be page-aligned, since the GC expects the