Kaffe Memory Manager

[Chris Pedley]

I'm having some trouble understanding Kaffe's memory manager
and there is one particular part that is confusing me a lot.
In gc-mem.c, function gc_block_alloc (about line 881) appears:
        if (GCMEM2BLOCK(heap_addr + size) 
            > ((gc_block *)gc_block_base) + nblocks
            || heap_addr < gc_heap_base) {

what is this test for?

Thanks,
Chris.