Anyone recognize this?

network>   tests/Network/SocketSpec.hs:111:9:
network>   1) Network.Socket.getAddrInfo works for IPv6 address
network>        uncaught exception: IOException of type NoSuchThing
network>        Network.Socket.getAddrInfo (called with preferred socket type/protocol: AddrInfo {addrFlags = [AI_NUMERICHOST,AI_ADDRCONFIG], addrFamily = AF_UNSPEC, addrSocketType = NoSocketType, addrProtocol = 0, addrAddress = 0.0.0.0:0, addrCanonName = Nothing}, host name: "2001:0db8:85a3:0000:0000:8a2e:0370:7334", service name: Nothing): does not exist (Address family for hostname not supported)
network>   To rerun use: --match "/Network.Socket/getAddrInfo/works for IPv6 address/" --seed 102858746
network>   tests/Network/Socket/ByteStringSpec.hs:268:9:
network>   2) Network.Socket.ByteString.recvMsg receives control messages for IPv6
network>        uncaught exception: IOException of type UnsupportedOperation
network>        Network.Socket.bind: unsupported operation (Cannot assign requested address)
network>   To rerun use: --match "/Network.Socket.ByteString/recvMsg/receives control messages for IPv6/" --seed 102858746

From 092c565d333be1e17b4779ac22104338941d913f (~5 days ago)

In reply to @jean-paul.:matrix.org
nope, Linux - but CircleCI

Just guessing, but is it because the kernel has IPv6 disabled via sysctl or perhaps even via kconfig?

Nix builds are sensitive to the host kernel.