#40 undefined reference to symbol 'XInternAtom'

Building of v7.3 in the latest Arch Linux environment ends with an error message:

...
[ 95%] [ 97%] Building CXX object src/CMakeFiles/kchmviewer.dir/treeitem_toc.o
Building CXX object src/CMakeFiles/kchmviewer.dir/treeitem_index.o
[100%] Building CXX object src/CMakeFiles/kchmviewer.dir/qrc_images.o
Linking CXX executable kchmviewer
/usr/bin/ld: CMakeFiles/kchmviewer.dir/mainwindow.o: undefined reference to symbol 'XInternAtom'
/usr/lib/libX11.so.6: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
src/CMakeFiles/kchmviewer.dir/build.make:828: recipe for target 'src/kchmviewer' failed
make[2]: *** [src/kchmviewer] Error 1
CMakeFiles/Makefile2:190: recipe for target 'src/CMakeFiles/kchmviewer.dir/all' failed
make[1]: *** [src/CMakeFiles/kchmviewer.dir/all] Error 2
Makefile:117: recipe for target 'all' failed
make: *** [all] Error 2
==> ERROR: A failure occurred in build().
Aborting...
==> ERROR: Build failed

Used PKGBUILD instruction can be found here:
https://projects.archlinux.org/svntogit/community.git/tree/trunk/PKGBUILD?h=packages/kchmviewer
No extra patching, just the usual instruction used.

[Anonymous]

Seems like changing dependency to QT5 and updating build instructions allowed the package to build. Looking forward to have the usual 'make install' instructions available too in the future. I guess this ca be closed then.