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

[Josh Triplett]

Package: aptitude
Version: 0.8.13-1+b1
Severity: normal

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

-- Package-specific info:
Terminal: xterm-256color
$DISPLAY is set.
which aptitude: /usr/bin/aptitude

aptitude version information:
aptitude 0.8.13
Compiler: g++ 9.3.0
Compiled against:
  apt version 6.0.0
  NCurses version 6.2
  libsigc++ version: 2.10.2
  Gtk+ support disabled.
  Qt support disabled.

Current library versions:
  NCurses version: ncurses 6.2.20200212
  cwidget version: 0.5.18
  Apt version: 6.0.0

aptitude linkage:
	linux-vdso.so.1 (0x00007ffe12fe1000)
	libapt-pkg.so.6.0 => /usr/lib/x86_64-linux-gnu/libapt-pkg.so.6.0 (0x00007f8b63e9f000)
	libncursesw.so.6 => /lib/x86_64-linux-gnu/libncursesw.so.6 (0x00007f8b63e64000)
	libtinfo.so.6 => /lib/x86_64-linux-gnu/libtinfo.so.6 (0x00007f8b63e35000)
	libsigc-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libsigc-2.0.so.0 (0x00007f8b63e2c000)
	libcwidget.so.4 => /usr/lib/x86_64-linux-gnu/libcwidget.so.4 (0x00007f8b63d26000)
	libsqlite3.so.0 => /usr/lib/x86_64-linux-gnu/libsqlite3.so.0 (0x00007f8b63bfa000)
	libboost_iostreams.so.1.71.0 => /usr/lib/x86_64-linux-gnu/libboost_iostreams.so.1.71.0 (0x00007f8b63bd1000)
	libxapian.so.30 => /usr/lib/x86_64-linux-gnu/libxapian.so.30 (0x00007f8b639b7000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f8b63996000)
	libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f8b637c9000)
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f8b63684000)
	libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f8b6366a000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f8b634a5000)
	libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007f8b6348d000)
	libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f8b63470000)
	libbz2.so.1.0 => /lib/x86_64-linux-gnu/libbz2.so.1.0 (0x00007f8b6345d000)
	liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007f8b63434000)
	liblz4.so.1 => /usr/lib/x86_64-linux-gnu/liblz4.so.1 (0x00007f8b63412000)
	libzstd.so.1 => /usr/lib/x86_64-linux-gnu/libzstd.so.1 (0x00007f8b63333000)
	libudev.so.1 => /lib/x86_64-linux-gnu/libudev.so.1 (0x00007f8b63307000)
	libsystemd.so.0 => /lib/x86_64-linux-gnu/libsystemd.so.0 (0x00007f8b63259000)
	libgcrypt.so.20 => /usr/lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007f8b6313c000)
	/lib64/ld-linux-x86-64.so.2 (0x00007f8b644e8000)
	libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f8b63137000)
	librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f8b6312a000)
	libuuid.so.1 => /usr/lib/x86_64-linux-gnu/libuuid.so.1 (0x00007f8b63121000)
	libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007f8b630fb000)

-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable-debug
  APT policy: (500, 'unstable-debug'), (500, 'unstable'), (1, 'experimental-debug'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 5.6.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE=C.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages aptitude depends on:
ii  aptitude-common           0.8.13-1
ii  libapt-pkg6.0             2.1.6
ii  libboost-iostreams1.71.0  1.71.0-6+b2
ii  libc6                     2.30-8
ii  libcwidget4               0.5.18-5
ii  libgcc-s1                 10.1.0-4
ii  libncursesw6              6.2-1
ii  libsigc++-2.0-0v5         2.10.2-1
ii  libsqlite3-0              3.32.3-1
ii  libstdc++6                10.1.0-4
ii  libtinfo6                 6.2-1
ii  libxapian30               1.4.15-1

Versions of packages aptitude recommends:
ii  libdpkg-perl    1.19.7
ii  sensible-utils  0.0.12+nmu1

Versions of packages aptitude suggests:
pn  apt-xapian-index                <none>
pn  aptitude-doc-en | aptitude-doc  <none>
pn  debtags                         <none>
pn  tasksel                         <none>

-- no debconf information