libzmq misconfigured? >=4.0 && <5.0, not found in the pkg-config database

[ocramz]

There are a bunch of failed doc builds mentioning conflict: pkg-config package libzmq>=4.0 && <5.0, not found in the pkg-config database. The relevant libzmq3-dev is in packages.txt however.

Example build logs :

• https://hackage.haskell.org/package/zeromq4-haskell-0.8.0/reports/2

References:

http://wiki.zeromq.org/distro:debian

[gbaz]

I imagine the library is there, but it is an older version than the package requires.