[Aptitude-devel] Bug#963716: Bug#963716: Dependency resolution led to additional problem requiring further dependency resolution

[Axel Beckert]

Control: tag -1 + confirmed

Hi Josh,

Josh Triplett wrote:
> When trying to upgrade current unstable, I encountered a dependency
> resolution issue I've never seen in aptitude before. Because "chromium
> conflicts with libavcodec58 (= 7:4.3-2)", aptitude suggested the
> solution of removing libavcodec58 and installing libavcodec-extra58.
> However, accepting that solution (pressing '!') then introduced new
> problems, where libavcodec-extra58's dependencies weren't satisfied.

Indeed, I ran into this, too with chromium and libavcodec58, too.
Don't remember all the details anymore, though.

> Accepting *that* solution by pressing '!' again turned up the problem
> that "chromium (upgrade, 81.0.4044.92-1 -> 83.0.4103.116-1) conflicts
> with libavcodec58 (= 7:4.3-2) (provided by libavcodec-extra58 7:4.3-2)".

I didn't notice that this goes further recursively as I intervened and
solved this myself. And since it so far only surfaced one single time,
I didn't think much about it.

But the way you describe it sounds more severe than I expected. It
also shows that this wasn't just a one-time issue showing up on only
my system.

> It seems like aptitude wasn't actually evaluating the consequences of
> its proposed dependency resolutions to ensure they reached a valid
> dependency state.

Ack. This is though probably nothing new and only surfaced through the
current situation around chromium and ffmpeg where (dependency-wise)
you either can have ffmpeg from testing and chromium from unstable or
vice versa.

		Regards, Axel
-- 
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