Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] next goal: HQu (user goal)
[__0] rejecting: HQu-0.0.0.4 (conflict: pkg-config package gsl-any, not found
in the pkg-config database)
[__0] rejecting: HQu-0.0.0.3, HQu-0.0.0.2, HQu-0.0.0.1, HQu-0.0.0.0
(constraint from user target requires ==0.0.0.4)
[__0] fail (backjumping, conflict set: HQu)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: HQu