#603 Firebird driver doesn't work on FPC trunk

[marsupilami79]

Due to a bug in FPC the Firebird driver doesn't work on FPC trunk. A tickt was created with the FPC people: https://gitlab.com/freepascal.org/fpc/source/-/issues/40810

Users are advised switch to the legacy API by adding FirebirdAPI=legacy to TZConnection.Properties if they absolutely need to use FPC trunk.

[marsupilami79]

So - the FPC devs answered to our ticket:

This is a known issue with Firebird, however the error is in the implementation:
The implementation as shown implicitly assumes that TObject has no fields. This is no longer correct in FPC trunk.
You must define a record with function pointers and use that instead.

This seems to be a lot of work. It seems that the people at MWA Software have a correct translation:
https://www.mwasoftware.co.uk/fb-pascal-api

See the file fbintf/client/3.0/firebird/FirebirdOOAPI.pas in their fbintf package. I am not sure, if we can use that file without problems though for licensing reasons.