Pete Buelow wrote:
> I'm trying to build FlightGear for FC4 on an nifty new amd64 game
> machine. I used to fly on a slightly slower Athlon, but want to
> step up to the plate and see if things are that much better with
> my new video card and 64 bit processor. Here's the issue.
> [... a spot where a pointer is cast to an int ...]

Yes, gcc 4.0 will not allow you to directly cast a pointer to an
integer on systems where their sizes differ, due to the
information loss problem (which is real in this case, as the
value is used as an "ID").  I think I posted this a while back,
but maybe I just remember thinking about doing it.

On my build, I just hacked the casts (I think there are two,
actually) to be of the form:


This "double cast" construction compiles and works.  At least on
my system, you can verify using pmap that there is no heap memory
mapped to addresses that are equal "modulo 2^32", so there is no
possibility of collision.  It really isn't an appropriate
permanent solution, though.  The ID values should be guaranteed
to be unique on all platforms.


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