The ebuild for plasma-workspace-4.10.2 has a conditional dependency (USE=semantic-desktop) on nepomuk-core, but the build itself apparently discovers the presence or absence of nepomuk by itself. This causes a build failure when an old (<4.10) version of nepomuk is installed but semantic-desktop is disabled so that the ebuild doesn't upgrade it. Unmerging the outdated nepomuk and nepomuk-core packages and restarting the build succeeds.
If semantic-desktop is disabled, the ebuild should either block on having nepomuk and nepomuk-core installed or tell the plasma-workspace build not to build the nepomuksearchrunner.
Please attach build.log and emerge --info.
Adding $(cmake-utils_use_find_package semantic-desktop NepomukCore) may work around the issue.
This problem occurs because KdepimLibsConfig.cmake calls find_package(NepomukCore) unconditionally.
kdepimlibs has not supported optional semantic-desktop for some time, and our patches are fragile and difficult to maintain. I propose we provide optional semantic-desktop only where supported by upstream. (Note, I have been told that semantic-desktop features can be disabled easily at runtime.)
Created attachment 347838 [details]
I'm sorry, I saw the e-mail while I was away and forgot to follow up.
I'm afraid that I neglected to copy build.log out of PORTAGE_TMPDIR before the successful build clobbered it, but here's my emerge --info.
Regarding the elimination of the semantic-desktop USE flag entirely, this would resolve this bug, but the last time I tried the semantic desktop (4.8), the KDE team's claims that you could disable it were bogus. Nothing I could do, including .kde symlink twiddling, could keep it from launching a full instance of mysqld to do absolutely nothing useful, even when I got a screenful of complaining notifications. If this has changed, I'd be quite happy if the flag were removed.
This issue will disappear KDE/4.11 since we are removing the semantic-desktop USE flag.
Should be fixed since some time