Plasma failed to start after downgrade to stable version

joe6302413

Hi,
I tried to downgrade my whole system to amd64 stable. And after the reemerge the kde can't start and showed me this message,
Plasma is unable to start as it could not correctly use opengl2. Please check that your graphic drivers are set up correctly.

I found the post https://forums.gentoo.org/viewtopic-p-8026100.html, and tried the eselect opengl as well as moving the .kde file. However, the same issue is still there.

Is anyone know what should I check to correct this problem?

Added url tags to exclude the comma from the link, thereby avoiding a 404. -- desultory

joe6302413 · Posted: Fri Oct 13, 2017 4:06 am Post subject:

Emerge --info
https://pastebin.com/XAF9RYPM

asturm · Developer Joined: 05 Apr 2007 Posts: 8936

Did you downgrade from Qt5.9 to Qt5.7?

joe6302413 · Posted: Fri Oct 13, 2017 10:37 am Post subject:

fedeliallalinea · Posted: Fri Oct 13, 2017 11:56 am Post subject:

joe6302413 · Posted: Fri Oct 13, 2017 2:02 pm Post subject:

asturm · Developer Joined: 05 Apr 2007 Posts: 8936

Only the emerge.log can tell us if you had downgraded from 5.9 - and that is guaranteed to break your system.

joe6302413 · Posted: Mon Oct 16, 2017 2:14 am Post subject:

Thank asturm for your reply.
I checked with my log file, and I didn't downgrade my system from qt 5.9.
My build didn't upgrade or rebuild for more than one month ago.
Another clue I just remembered is I changed my rendering backend from opengl 2 to opengl 3.
Sorry for the late response. My computer was not close to me in the weekend.

joe6302413 · Posted: Tue Oct 17, 2017 4:58 am Post subject:

Now I am trying to eliminating the egl flag, though my previous build works well without excluded the egl Flag.
I found my qtgui build with this flag and it is required by qtwayland and kwayland.
Does anyone know how to work around these conflict?

asturm · Developer Joined: 05 Apr 2007 Posts: 8936

Don't do that.

joe6302413 · Posted: Tue Oct 17, 2017 7:14 am Post subject:

joe6302413 · Posted: Wed Oct 25, 2017 3:02 pm Post subject:

Recently, upgrading some packages (newly stablized) and hope the build will get back to original.
However, the wpa-supplicant cannot successfully emerged, and I guess the error is correlated to the qt system.
Here is my emerge --info https://pastebin.com/ah5RVCrm
emerge -pqv wpasupplicant [ebuild U ] net-wireless/wpa_supplicant-2.6-r3 [2.6-r2] USE="dbus hs2-0 qt5 readline ssl -ap -eap-sim -fasteap -gnutls (-libressl) -p2p (-ps3) (-selinux) -smartcard -tdls -uncommon-eap-types (-wimax) -wps"

The error message https://pastebin.com/7titX5tA

Hope it is related to the original problem!!
Many thanks.

asturm · Developer Joined: 05 Apr 2007 Posts: 8936

Yes, this looks like another botched gcc5 upgrade. Did you read and follow the gcc ABI breakage news item after the switch?

joe6302413 · Posted: Fri Oct 27, 2017 5:45 am Post subject: