problems upgrading from 14.04 to 16.04

[Colin Law]

On 26 September 2016 at 16:02, J.L. Blom <joep at neuroweave.nl> wrote:
> On 26/09/16 15:36, Tom H wrote:
>>
>> Run
>> apt-get install -s gcc-5-base=5.4.0-6ubuntu1~16.04.2
>> to check what'll happen.
>>
>> If it looks OK, run
>> apt-get install gcc-5-base=5.4.0-6ubuntu1~16.04.2
>>
>> If that doesn't work, you'll have to try to force it:
>>
>> apt-get install -s -o Dpkg::Options::="--force-all"
>> gcc-5-base=5.4.0-6ubuntu1~16.04.2
>> then
>> apt-get install -o Dpkg::Options::="--force-all"
>> gcc-5-base=5.4.0-6ubuntu1~16.04.2
>>
> Tom, thanks for the suggestions.
> First, I don't think I downloaded this from a testing PPA as I always use
> only LTS for ubuntu.
> Second, I followed your suggestions and neither the first nor the forged
> second version did do anything else than the chicken and egg problem. I
> think something -not directly mentioned in the error messages prevents the
> re-installation of the gcc-5-base library.
> Maybe I have to forcibly remove this library, hoping at doesn't corrupt
> completely the rest of the system.
> But any suggestion is welcome.

I think the thing to do may be to remove the package that has the
unmet dependencies first so first to check it does not try and remove
half the system run (the -s means simulate)
sudo apt remove -s libstdc++6
if that is ok run it again without the -s and then the install -f and
if still ok remove and re-install gcc-5-base.

If you have any problems with the above please copy/paste from the
terminal the command and result so there is no confusion about what
you have tried.

Colin