On Fri, 19 Dec 2008, Mark Morgan Lloyd wrote:
> I've got a few thousand lines of Pascal which I'm converting to FPC. It's > actually the Meta-2 compiler-compiler which despite its age I still find > useful for embedded script processing, I hope eventually to get it running on > SPARC and possibly ARM as well as x86. Linux will not be the first OS this > code has run on, by any means. > > This code was originally written using MT+86, but compatibility with that has > been sacrificed and it now works with TopSpeed Pascal, TP5.5 and Delphi. > Because it is still compilable with TopSpeed which doesn't use the "standard" > directive and conditional-compilation format I'm having to be very careful > with the source. > > In one place I am checking a number of procedure variables which are actually > callbacks for reading input etc., if they're NIL then default procedures are > used instead. For portability I have defined myself a function > > FUNCTION AddressOf(VAR x): POINTER; > > Hence > > IF AddressOf(source) <> NIL THEN > state.source:= source > ELSE > state.source:= dummyRead; > > That works OK with the other compilers but when compiling with FPC it reports > "Wrong number of parameters specified for call to "<Procedure > Variable>". > > If instead I use > > IF @source <> NIL THEN > state.source:= source > ELSE > state.source:= dummyRead; > > that works with FPC and probably other Borland-style compilers, but not with > TopSpeed. > > Is there a directive or mode that will allow a procedure variable to be > compatible with AddressOf() as defined? Alternatively is there a type which is > compatible with any procedure variable (i.e. like Modula-2's PROC, if my > memory is correct), and can I overload AddressOf() to handle the specific case > of a procedure passed as parameter while leaving it tolerant of other types? No you cannot. Did you try using Delphi mode ? The compiler uses other rules then. Michael. _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
