As people following recent commits might have already seen, work is being done to switch the Windows header units to unicode (-W), and switch base file operations to use it.

That is not (yet) committed, but some minor other work has been committed. The following IFDEF defines are used for that:

FPC_HAS_SYSTEMFILEREC -> textrec/filerec use unicode (compiler must match) FPC_UNICODE_RTL -> core system routines support unicode FPC_OS_UNICODE -> (windows) OS headers are unicode

UNICODE -> {$mode delphunicode} string=unicodestring but also locally defined in the various windows api units ({$ifdef FPC_OS_UNICODE} {$DEFINE UNICODE}{$ENDIF} in the headers.

There is nothing that can be built from SVN yet, so please be patient.