I'm trying to install qtcreator or any other qt development package but it's not working because of broken packages. I then tried to install qtcreator manually from the qt website but I can't compile anything because of this error
cannot find -lGL.
I then tried installing libgl1-mesa-dev and I get the same error as when installing qtcreator:
> sudo apt-get install libgl1-mesa-dev Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: libgl1-mesa-dev : Depends: mesa-common-dev (= 13.0.6-1+b2) but it is not going to be installed Depends: libdrm-dev (>= 2.4.69) but it is not going to be installed Depends: libxcb-dri3-dev but it is not going to be installed E: Unable to correct problems, you have held broken packages.
It may have something to do with my sources.list, I added this:
deb http://ftp.fr.debian.org/debian testing main non-free contrib deb-src http://ftp.fr.debian.org/debian testing main non-free contrib
And I'm using debian 9.9 stable, I installed some packages using
sudo apt-get -t testing install <package>
Did I broke my system? Is there a way to fix it or should I reinstall it?