Resolving dependencies... Configuring cereal-0.5.4.0... Configuring mtl-2.2.1... Building cereal-0.5.4.0... Building mtl-2.2.1... Installed mtl-2.2.1 Configuring network-2.6.3.1... Configuring random-1.1... Installed cereal-0.5.4.0 Building random-1.1... Building network-2.6.3.1... Configuring stm-2.4.4.1... Installed random-1.1 Building stm-2.4.4.1... Configuring transformers-compat-0.5.1.4... Installed stm-2.4.4.1 Building transformers-compat-0.5.1.4... Configuring text-1.2.2.1... Installed transformers-compat-0.5.1.4 Installed network-2.6.3.1 Configuring network-data-0.5.3... Building text-1.2.2.1... Building network-data-0.5.3... Configuring exceptions-0.8.3... Installed network-data-0.5.3 Building exceptions-0.8.3... Installed exceptions-0.8.3 Configuring bimap-0.3.2... Building bimap-0.3.2... Installed bimap-0.3.2 Installed text-1.2.2.1 Configuring parsec-3.1.11... Building parsec-3.1.11... Installed parsec-3.1.11 Configuring nettle-openflow-0.1... Building nettle-openflow-0.1... Failed to install nettle-openflow-0.1 Build log ( /home/builder/.cabal/logs/nettle-openflow-0.1.log ): cabal: Entering directory '/tmp/cabal-tmp-30827/nettle-openflow-0.1' Configuring nettle-openflow-0.1... Building nettle-openflow-0.1... Preprocessing library nettle-openflow-0.1... [ 1 of 18] Compiling Nettle.Servers.TwoWayChannel ( src/Nettle/Servers/TwoWayChannel.hs, dist/build/Nettle/Servers/TwoWayChannel.o ) src/Nettle/Servers/TwoWayChannel.hs:45:33: warning: [-Wdeprecations] In the use of ‘isEmptyChan’ (imported from Control.Concurrent, but defined in Control.Concurrent.Chan): Deprecated: "if you need this operation, use Control.Concurrent.STM.TChan instead. See for details" [ 2 of 18] Compiling Nettle.Servers.TCPServer ( src/Nettle/Servers/TCPServer.hs, dist/build/Nettle/Servers/TCPServer.o ) src/Nettle/Servers/TCPServer.hs:33:1: error: Duplicate instance declarations: instance Ord SockAddr -- Defined at src/Nettle/Servers/TCPServer.hs:33:1 instance Ord SockAddr -- Defined in ‘network-2.6.3.1:Network.Socket.Types’ cabal: Leaving directory '/tmp/cabal-tmp-30827/nettle-openflow-0.1' cabal: Error: some packages failed to install: nettle-frp-0.1.1 depends on nettle-openflow-0.1 which failed to install. nettle-openflow-0.1 failed during the building phase. The exception was: ExitFailure 1