At the "make install" stage of (e.g.) kig package a small directory structure starting with
"share" is created in the sources root.  This has the ownership of the issuer of "make install"
(typically "root") inside a directory structure that typically is owned by a normal user.

Reproducible: Always

Steps to Reproduce:
1. git clone git@git.kde.org:kig
2. cd kig
3. cmake . [options]
4. make
5. make install

Actual Results:  
$ pwd
/home/matem/paolini/Git/kdeedu/kig
$ ls -ld .
drwxr-xr-x 21 paolini matem 4096 19 mar 14.25 .
$ ls -ld share                   # this directory shouldn't even be there!
drwxr-xr-x 4 root root 4096 19 mar 15.00 share



Expected Results:  
There should be anything owned by root in the users home directory!

in
function(_ecm_update_iconcache installdir theme)
I find these two commands:

        file(WRITE \"${installdir}/${theme}/temp.txt\" \"update\")
        file(REMOVE \"${installdir}/${theme}/temp.txt\")

They are apparently missing a ${CMAKE_INSTALL_PREFIX}/ prefix... I am not sure what is the purpose of temp.txt, perhaps it is some kind of lock file... however it shouldn't use the source tree.  It might even be impossible for "root" to write here, e.g. in case of an NFS-mounted home, where "root" is typically mapped into the "nfsnobody" user on the NFS server.

The bug report https://bugs.kde.org/show_bug.cgi?id=360614 is where the problem was first spotted.