Bug#844810: lambdabot: FTBFS: unsatisfiable build-dependencies: libghc-lambdabot-haskell-plugins-dev (< 5.2), libghc-lambdabot-haskell-plugins-dev (>= 5.1)

[Lucas Nussbaum]

Source: lambdabot
Version: 5.1-2
Severity: serious
Tags: stretch sid
User: debian-qa at lists.debian.org
Usertags: qa-ftbfs-20161118 qa-ftbfs
Justification: FTBFS on amd64

Hi,

During a rebuild of all packages in sid, your package failed to build on
amd64.

Relevant part (hopefully):
> +------------------------------------------------------------------------------+
> | Install package build dependencies                                           |
> +------------------------------------------------------------------------------+
> 
> 
> Setup apt archive
> -----------------
> 
> Merged Build-Depends: cdbs, debhelper (>= 10), ghc (>= 8), ghc-prof, haskell-devscripts (>= 0.13), libghc-lambdabot-core-dev (<< 5.2), libghc-lambdabot-core-dev (>= 5.1), libghc-lambdabot-haskell-plugins-dev (<< 5.2), libghc-lambdabot-haskell-plugins-dev (>= 5.1), libghc-lambdabot-irc-plugins-dev (<< 5.2), libghc-lambdabot-irc-plugins-dev (>= 5.1), libghc-lambdabot-misc-plugins-dev (<< 5.2), libghc-lambdabot-misc-plugins-dev (>= 5.1), libghc-lambdabot-novelty-plugins-dev (<< 5.2), libghc-lambdabot-novelty-plugins-dev (>= 5.1), libghc-lambdabot-reference-plugins-dev (<< 5.2), libghc-lambdabot-reference-plugins-dev (>= 5.1), libghc-lambdabot-social-plugins-dev (<< 5.2), libghc-lambdabot-social-plugins-dev (>= 5.1), libghc-mtl-dev (>= 2)
> Filtered Build-Depends: cdbs, debhelper (>= 10), ghc (>= 8), ghc-prof, haskell-devscripts (>= 0.13), libghc-lambdabot-core-dev (<< 5.2), libghc-lambdabot-core-dev (>= 5.1), libghc-lambdabot-haskell-plugins-dev (<< 5.2), libghc-lambdabot-haskell-plugins-dev (>= 5.1), libghc-lambdabot-irc-plugins-dev (<< 5.2), libghc-lambdabot-irc-plugins-dev (>= 5.1), libghc-lambdabot-misc-plugins-dev (<< 5.2), libghc-lambdabot-misc-plugins-dev (>= 5.1), libghc-lambdabot-novelty-plugins-dev (<< 5.2), libghc-lambdabot-novelty-plugins-dev (>= 5.1), libghc-lambdabot-reference-plugins-dev (<< 5.2), libghc-lambdabot-reference-plugins-dev (>= 5.1), libghc-lambdabot-social-plugins-dev (<< 5.2), libghc-lambdabot-social-plugins-dev (>= 5.1), libghc-mtl-dev (>= 2)
> dpkg-deb: building package 'sbuild-build-depends-lambdabot-dummy' in '/<<BUILDDIR>>/resolver-k5i2Fu/apt_archive/sbuild-build-depends-lambdabot-dummy.deb'.
> dpkg-scanpackages: warning: Packages in archive but missing from override file:
> dpkg-scanpackages: warning:   sbuild-build-depends-lambdabot-dummy
> dpkg-scanpackages: info: Wrote 1 entries to output Packages file.
> Ign:1 copy:/<<BUILDDIR>>/resolver-k5i2Fu/apt_archive ./ InRelease
> Get:2 copy:/<<BUILDDIR>>/resolver-k5i2Fu/apt_archive ./ Release [963 B]
> Ign:3 copy:/<<BUILDDIR>>/resolver-k5i2Fu/apt_archive ./ Release.gpg
> Get:4 copy:/<<BUILDDIR>>/resolver-k5i2Fu/apt_archive ./ Sources [477 B]
> Get:5 copy:/<<BUILDDIR>>/resolver-k5i2Fu/apt_archive ./ Packages [568 B]
> Fetched 2008 B in 0s (0 B/s)
> Reading package lists...
> W: No sandbox user '_apt' on the system, can not drop privileges
> Reading package lists...
> 
> Install lambdabot build dependencies (apt-based resolver)
> ---------------------------------------------------------
> 
> Installing build dependencies
> Reading package lists...
> Building dependency tree...
> Reading state information...
> 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:
>  sbuild-build-depends-lambdabot-dummy : Depends: libghc-lambdabot-haskell-plugins-dev (< 5.2) but it is not going to be installed
>                                         Depends: libghc-lambdabot-haskell-plugins-dev (>= 5.1) but it is not going to be installed
> E: Unable to correct problems, you have held broken packages.
> apt-get failed.

The full build log is available from:
   http://aws-logs.debian.net/2016/11/18/lambdabot_5.1-2_unstable.log

A list of current common problems and possible solutions is available at
http://wiki.debian.org/qa.debian.org/FTBFS . You're welcome to contribute!

About the archive rebuild: The rebuild was done on EC2 VM instances from
Amazon Web Services, using a clean, minimal and up-to-date chroot. Every
failed build was retried once to eliminate random failures.