error: `prefkeys.gpi' must be recompiled?

I'm using gp, and it is giving me the following error:

/Source/InterarchySupportBundle.p:18: error: `prefkeys.gpi' must be recompiled

Clearly this is actually a gpc error. I've attached a -v3 output from gp. Interestingly, it ends with:

/Source/PrefKeys.p: recompiling because interface of `GPCMacOSAll.pas' has changed /Source/InterarchySupportBundle.p: recompiling because an interface used indirectly has changed

and then proceeds to compile InterarchySupportBundle.p, so GPC may well be quite correct that PrefKeys.p does indeed need recompiling and gp either skipped it for some reason or is doing it in the wrong order.

Any ideas as to why this might happen or what I should look in to to try to debug the cause?

I'm guessing that the cyclic dependencies (in the implementation section) are causing problems. Peter.

gp -v3 -g -gstabs -O0 --uses=GPCMacOSAll --no-check-platform -DINTERARCHY -Wall --unit-path=/Developer/Pascal/GPCPInterfaces:/Source/PNLLibraries:/Source/MacOSXSupport:/Source:/Build --object-path=/IAObjects --unit-destination-path=/IAObjects --Pascal=--include=/Source/PNLLibraries/Prefix.GPC --c=-no-cpp-precomp --c=-I/Developer/Headers/FlatCarbon --c=-I/usr/include/libxml2 --c=-flat_namespace /Source/URLFiles.p gpc -dumpmachine gpc -dumpversion gpc -print-file-name=units gpc --print-needed-options -x Preprocessed-Pascal /var/tmp/GPaaa00594 Needed option for GPC: -D__ppc__ Needed option for GPC: -D__POWERPC__ Needed option for GPC: -D__NATURAL_ALIGNMENT__ Needed option for GPC: -D__MACH__ Needed option for GPC: -D__APPLE__ /Source/URLFiles.p: compiling because target files not found or not up to date /Source/BaseGlobals.p: compiling because target files not found or not up to date /Source/Logs.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyCleverAlerts.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyInternetConfig.p: recompiling interface because source has changed /Source/PNLLibraries/MyInternetConfig.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyKeychain.p: compiling implementation because target files not found or not up to date /Source/PNLLibraries/MyScrap.p: compiling implementation because target files not found or not up to date /Source/PNLLibraries/MyAEUtils.p: compiling implementation because target files not found or not up to date /Source/Utils.p: compiling because target files not found or not up to date /Source/Permissions.p: compiling because target files not found or not up to date /Source/DisplayWindow.p: compiling because target files not found or not up to date /Source/FileMapping.p: compiling implementation because target files not found or not up to date /Source/InterarchyIcons.p: compiling because target files not found or not up to date /Source/PrefKeys.p: compiling implementation because target files not found or not up to date /Source/ReportPrinting.p: compiling implementation because target files not found or not up to date /Source/TransferMode.p: compiling because target files not found or not up to date /Source/Transcript.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyCarbonEvents.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyControls.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyNotifier.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyProcesses.p: recompiling interface because source has changed /Source/PNLLibraries/MyProcesses.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyUnicode.p: compiling because target files not found or not up to date /Source/InterarchyInterface.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyDrag.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyWindow.p: compiling because target files not found or not up to date /Source/ActionToolbarItem.p: compiling because target files not found or not up to date /Source/EditWith.p: compiling because target files not found or not up to date /Source/Resume.p: compiling because target files not found or not up to date /Source/TransferActions.p: compiling because target files not found or not up to date /Source/TransferProgress.p: compiling because target files not found or not up to date /Source/URLMapping.p: compiling because target files not found or not up to date /Source/ViewWith.p: compiling because target files not found or not up to date /Source/GenericBookmarkWindow.p: compiling because target files not found or not up to date /Source/TransferNotificationCenter.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyTextDisplayWindow.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyAppearance.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyHIToolbar.p: compiling because target files not found or not up to date /Source/BookmarkManager.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyApplication.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyEditTextToolbarItem.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyHIView.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyNavigation.p: compiling because target files not found or not up to date /Source/PNLLibraries/MySegmentedView.p: compiling because target files not found or not up to date /Source/SendRecordedCommand.p: compiling because target files not found or not up to date /Source/TemporaryFiles.p: compiling because target files not found or not up to date /Source/CheckWebWindow.p: compiling because target files not found or not up to date /Source/DirectoryList.p: compiling because target files not found or not up to date /Source/DirectoryPathList.p: compiling because target files not found or not up to date /Source/DirectoryRemoveList.p: compiling because target files not found or not up to date /Source/DirectorySpecList.p: compiling because target files not found or not up to date /Source/HTTPPathList.p: compiling because target files not found or not up to date /Source/HTTPPathSuccess.p: compiling because target files not found or not up to date /Source/MirrorCache.p: compiling because target files not found or not up to date /Source/MirrorFileCollection.p: compiling because target files not found or not up to date /Source/MirrorFTPDiskPathList.p: compiling because target files not found or not up to date /Source/MirrorPutMembers.p: compiling because target files not found or not up to date /Source/MirrorPutPathList.p: compiling because target files not found or not up to date /Source/MirrorReportWindow.p: compiling because target files not found or not up to date /Source/PNLLibraries/MySuspendedEvents.p: compiling because target files not found or not up to date /Source/NotifyUser.p: compiling because target files not found or not up to date /Source/ParseFTPList.p: compiling because target files not found or not up to date /Source/ParseHTMLFile.p: compiling because target files not found or not up to date /Source/Transfer.p: compiling because target files not found or not up to date /Source/TransferUtils.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyCustomControl.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyDataBrowser.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyTextDisplay.p: compiling because target files not found or not up to date /Source/AutoUploadsEngine.p: compiling because target files not found or not up to date /Source/BookmarksBar.p: compiling because target files not found or not up to date /Source/ChasingArrows.p: compiling because target files not found or not up to date /Source/FTPDiskScriptingSupport.p: compiling because target files not found or not up to date /Source/FTPDisksEngine.p: compiling because target files not found or not up to date /Source/QueueManager.p: compiling because target files not found or not up to date /Source/ScheduledBookmarksEngine.p: compiling because target files not found or not up to date /Source/SplitViewControl.p: compiling because target files not found or not up to date /Source/StartupItems.p: compiling because target files not found or not up to date /Source/FileActions.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyCharsets.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyTXNControl.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyPlayAsyncSound.p: compiling because target files not found or not up to date /Source/HostInfoMapping.p: compiling implementation because target files not found or not up to date /Source/HostUploadPermissionsMapping.p: compiling implementation because target files not found or not up to date /Source/PNLLibraries/MyDataBrowserColumnView.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyDataBrowserIconView.p: compiling because target files not found or not up to date /Source/PNLLibraries/MyFind.p: compiling because target files not found or not up to date /Source/ScheduleWindow.p: compiling because target files not found or not up to date /Source/PrefKeys.p: recompiling because interface of `GPCMacOSAll.pas' has changed /Source/InterarchySupportBundle.p: recompiling because an interface used indirectly has changed Compiling InterarchySupportBundle.p (603) gpc -D__ppc__ -D__POWERPC__ -D__NATURAL_ALIGNMENT__ -D__MACH__ -D__APPLE__ -g -gstabs -O0 -DINTERARCHY -Wall --unit-path=/Developer/Pascal/GPCPInterfaces:/Source/PNLLibraries:/Source/MacOSXSupport:/Source:/Build --object-path=/IAObjects --include=/Source/PNLLibraries/Prefix.GPC -I /IAObjects -I /IAObjects/ -I /Developer/Pascal/GPCPInterfaces -I /Source/PNLLibraries -I /Source/MacOSXSupport -I /Source -I /Build -I /IAObjects/ -I . -I /Developer/Pascal/gpc-20050331/lib/gcc/powerpc-apple-darwin8.1.0/3.4.3/units -I /Source/ --unit-path=/Source/ --gpi-destination-path=/IAObjects/ --unit-path=/IAObjects/ --no-automake -c -o /IAObjects/InterarchySupportBundle.o /Source/InterarchySupportBundle.p --uses=GPCMacOSAll /Source/InterarchySupportBundle.p:18: error: `prefkeys.gpi' must be recompiled