Resolving dependencies...
Configuring QIO-1.1...
Building QIO-1.1...
Preprocessing library QIO-1.1...
[ 1 of 12] Compiling QIO.Vec          ( QIO/Vec.hs, dist/build/QIO/Vec.o )
[ 2 of 12] Compiling QIO.QioSyn       ( QIO/QioSyn.hs, dist/build/QIO/QioSyn.o )
[ 3 of 12] Compiling QIO.Qdata        ( QIO/Qdata.hs, dist/build/QIO/Qdata.o )
[ 4 of 12] Compiling QIO.Heap         ( QIO/Heap.hs, dist/build/QIO/Heap.o )
[ 5 of 12] Compiling QIO.QioClass     ( QIO/QioClass.hs, dist/build/QIO/QioClass.o )
[ 6 of 12] Compiling QIO.VecEq        ( QIO/VecEq.hs, dist/build/QIO/VecEq.o )

QIO/VecEq.hs:52:29:
    Could not deduce (Eq x) arising from a use of `=='
    from the context (Num x)
      bound by the type signature for
                 vEqTimes :: Num x => x -> VecEqL x a -> VecEqL x a
      at QIO/VecEq.hs:51:13-52
    Possible fix:
      add (Eq x) to the context of
        the type signature for
          vEqTimes :: Num x => x -> VecEqL x a -> VecEqL x a
    In the expression: l == 0
    In a stmt of a pattern guard for
                   an equation for `vEqTimes':
      l == 0
    In an equation for `vEqTimes':
        l vEqTimes (VecEqL bs)
          | l == 0 = VecEqL []
          | otherwise = VecEqL (map (\ (b, k) -> (b, l * k)) bs)
Failed to install QIO-1.1
cabal: Error: some packages failed to install:
QIO-1.1 failed during the building phase. The exception was:
ExitFailure 1