Resolving dependencies...
cabal: Could not resolve dependencies:
trying: iptables-helpers-0.5.0 (user goal)
trying: base-4.9.0.0/installed-4.9... (dependency of iptables-helpers-0.5.0)
next goal: syb (dependency of iptables-helpers-0.5.0)
rejecting: syb-0.6, syb-0.5.1, syb-0.5, syb-0.4.4, syb-0.4.3, syb-0.4.2,
syb-0.4.1, syb-0.4.0 (conflict: iptables-helpers => syb>=0.3 && <0.4)
rejecting: syb-0.3.7, syb-0.3.6.2 (conflict: base==4.9.0.0/installed-4.9...,
syb => base>=4.0 && <4.8)
rejecting: syb-0.3.6.1, syb-0.3.6 (conflict: base==4.9.0.0/installed-4.9...,
syb => base>=4.0 && <4.6)
rejecting: syb-0.3.5, syb-0.3.4, syb-0.3.3 (conflict:
base==4.9.0.0/installed-4.9..., syb => base>=4.0 && <4.5)
rejecting: syb-0.3.2, syb-0.3.1, syb-0.3 (conflict:
base==4.9.0.0/installed-4.9..., syb => base>=4.0 && <4.4)
rejecting: syb-0.2.2, syb-0.2.1, syb-0.2, syb-0.1.0.3, syb-0.1.0.2,
syb-0.1.0.1, syb-0.1.0.0 (conflict: iptables-helpers => syb>=0.3 && <0.4)
Dependency tree exhaustively searched.