Thanks for the report! On Sat, May 19, 2012 at 2:02 PM, Christoph Anton Mitterer <calestyo@scientia.net> wrote: > I just tried to upgrade nagios-plugins-basic which now pre-depends > on nagios-plugins-common. This makes apt segfaulting (and of course also > anything that depends on apt (e.g. aptitude) Simplified error-condition: Installed: basic=1 (common is NOT installed) Candidates: basic=2 Pre-Depends: common common=2 Breaks: basic (<= 1) Looks like there is a reason for the policy §7.2 saying "You should not specify a Pre-Depends entry for a package before this has been discussed on the debian-devel mailing list" Anyway, apt shouldn't segfault in such a situation, especially as an (ugly) solution is possible by deconfiguring basic=1 before installing (and configuring) common=2 (ugly because "dpkg: considering deconfiguration" always sounds like it could decide against it). There is a check for these kind of loops, but it wrongly ignores new installs in an attempt to ignore non-installed pre-depends or-group members. Removing the first check (as the third one checks basically the same as 0 != V) fixes the problem here. The simulation doesn't like the solution and articulates this, but continues anyway and in a real run dpkg will "complain" as described earlier but continues as well. Best regards David Kalnischkies
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