Resolving dependencies... cabal: Could not resolve dependencies: trying: click-clack-1.0.1 (user goal) trying: base-4.8.1.0/installed-4f7... (dependency of click-clack-1.0.1) next goal: OpenGL (dependency of click-clack-1.0.1) rejecting: OpenGL-2.13.1.0, 2.13.0.0, 2.12.0.1, 2.12.0.0, 2.11.1.0, 2.11.0.0, 2.10.0.2, 2.10.0.1, 2.10.0.0, 2.9.2.0, 2.9.1.0, 2.9.0.0, 2.8.0.0, 2.6.0.1, 2.6.0.0 (conflict: click-clack => OpenGL>=2.4 && <2.6) trying: OpenGL-2.5.0.0 next goal: Tensor (dependency of OpenGL-2.5.0.0) rejecting: Tensor-1.1.0.1, 1.1.0.0 (conflict: OpenGL => Tensor==1.0.*) rejecting: Tensor-1.0.0.1, 1.0.0.0 (conflict: base==4.8.1.0/installed-4f7..., Tensor => base>=3 && <4.7) Dependency tree exhaustively searched.