[fpc-pascal] fast integer multiplication

[Peter Vreman]

> Now, concerning "both fpc and delphi". That Delphi code can be
> compiled with FPC is rather good thing but FPC has not to follow
> Delphi. The future of Pascal is not Delphi, it is FreePascal. And,
> no, for once, I am not joking. :-)

Most users expect the same behaviour in delphi and fpc. We get a lot of
bug reports if we make something incompatible. Even if we document things
properly  the users will start complaining. And projects like CrossFPC are
requesting even more compatibility with Kylix/Delphi.