The project file to check just GUI code was missing the directory
to check. This is probably due it was used originally as
"automatically" loaded project file which assumed current
directory is checked and only added some additional parameters.
GUI reads per-project settings (automatically deallocated classes) from XML project file. The project file format is described in projectfile.txt. Example project file is added for gui.
See also forum discussion at:
https://sourceforge.net/apps/phpbb/cppcheck/viewtopic.php?f=3&t=46