[KPhotoAlbum] error compiling in Ubuntu 16.04 and Mint 18.3

[Andreas Schleth]

Hi everybody,

when I try to build KPA from git master in those two systems, make fails 
with this error:

/home/as/kpa/kphotoalbum/DB/ImageInfo.cpp: In member function ‘bool 
DB::ImageInfo::hasCategoryInfo(const QString&, const StringSet&) const’:
/home/as/kpa/kphotoalbum/DB/ImageInfo.cpp:130:19: error: ‘const 
StringSet {aka const class QSet<QString>}’ has no member named ‘intersects’
      return values.intersects( m_categoryInfomation[key] );
                    ^
CMakeFiles/kphotoalbum.dir/build.make:2534: die Regel für Ziel 
„CMakeFiles/kphotoalbum.dir/DB/ImageInfo.cpp.o“ scheiterte

It builds nicely in openSuSE Leap 42.2. The main difference seems to be 
the version of gcc:

opensuse: gcc (SUSE Linux) 4.8.5

ubuntu 16.04 (and Mint): gcc (Ubuntu 5.4.0-6ubuntu1~16.04.5) 5.4.0 20160609

Any ideas?

Andreas