Since yesterday then possible macro's that can be used in the paths are changed. The following macro's are now supported, with examples of the value:

$fpcversion = 1.9.4
$fpcdate = compiler date
$fpccpu = i386
$fpcos = linux
$fpctarget = i386-linux

Also the * can now be used in one place in the middle of a path, this allows easy substitutions for the packages tree:

-Fu~/fpc/packages/base/*/units/$fpctarget
-Fu~/fpc/packages/extra/*/units/$fpctarget