I am getting an error about a missing package dependency that is already installed. I have seen versions of this questions about different packages and tried all those solutions, but I still can't figure out what the problem is or how to fix it. In summary: I am trying to apt-get install a package call libxmlada5-dev, which says it depends on a package called gnat. Fair enough, so I try to install gnat. But then gnat says it relies on gnat-4.9. Weird, but okay. So when I try to install gnat-4.9, it says it is actually already installed! I have tried uninstalling and re-installing gnat-4.9, I have tried sudo apt-get -f install
, I have tried apt clean, etc. None of these options do anything, since it seems like the dependency is already met.
Here is my specific error:
sudo apt-get install gnat
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:
gnat : Depends: gnat-4.9 but it is not going to be installed
and here is where I try to update the dependency:
Reading package lists... Done
Building dependency tree
Reading state information... Done
gnat-4.9 is already the newest version (4.9.3-3ubuntu5).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
finally, here is what I get with listapt-cache policy gnat
and gnat-4.9:
gnat:
Installed: (none)
Candidate: 4.9ubuntu2
Version table:
4.9ubuntu2 500
500 https://my-company-apt-mirror.corp/ubuntu xenial/universe amd64 Packages
gnat-4.9:
Installed: 4.9.3-3ubuntu5
Candidate: 4.9.3-3ubuntu5
Version table:
*** 4.9.3-3ubuntu5 500
500 https://my-company-apt-mirror.corp/ubuntu xenial/universe amd64 Packages
100 /var/lib/dpkg/status