[fpc-devel] Re: Comparison FPC 2.6.2 - Kylix 3

[Martin Schreiber]

On Monday 04 March 2013 14:37:40 Daniël Mantione wrote:

> Originally the compiler was doing the candidate selection with a simple
> loop through the parameters that took the first suitable match. When the
> type conversion matters became more complex the "Unable to determine
> overloaded procedure" error became increasingle annoying.
>
> At some point I did redesign it with scoring system: Each candidate that
> is compatible gets assigned a score how well the overloaded procedure
> matches the parameters. The best match is selected.
>
> At that point, the compiler became highly intelligent in finding the
> correct overloaded procedure/operator, but the amount of computing power
> involved with overloading went up: Instead of selecting the first
> candidate, we need to compute the score for all candidates. This even
> requires floating point arithmetic.
>
This improvement is very visible. I had big problems to make MSEide Delphi 
compatible because Delphi many times reported "Unable to determine overloaded 
procedure" where FPC has no problems. I think this is worth a slow down of 
compile time. :-)

Martin