C++ slow/swappy problem solved

[Tony Bryant <brd@paradise.net.nz>]

I've reduced the 160Mb compile down to 
this fragment:

-------------------------------------
class x
{
public:
    unsigned long mem[1024*1024*10];
    x();
};

class y : public x
{
public:
     y();
};
----------------------------------------

Some digging show that "record_subobject_offset" in class.c is being
called for EVERY item in x::mem

I now have enough info for a workaround, and I've put an entry in gnatsweb - 
Do with it what you will....

BTW- the allocated offset information isn't showing up in -fmem-report....