[arch-haskell] aura won't upgrade (looks like a cabal version issue)

[Martin DeMello]

I had the same problem (among others) while trying to install
haskell-elm, incidentally. it might be due to there being both

  haskell-core/cabal-install 1.18.0.3-8 [installed]
  extra/cabal-install 1.20.0.1-1 [installed: 1.18.0.3-8]

but haskell-core is before extra in my pacman.conf. full list of repos:

[core]
[haskell-core]
[haskell-happstack]
[infinality-bundle]
[infinality-bundle-fonts]
[extra]
[community]

-----------------------------------------------------------
Here's the issue:

$ cabal --version
cabal-install version 1.18.0.3
using version 1.18.1.3 of the Cabal library

$ sudo aura -A aura
aura >>= Determining dependencies...
aura >>= AUR Packages:
aura

aura >>= Continue? [Y/n] y
aura >>= Building `aura`...
aura >>= Well, building `aura` failed.
aura >>= Dumping makepkg output in 3.. 2.. 1..
==> Making package: aura 1.2.3.4-1 (Sun May 25 14:31:03 PDT 2014)
==> Checking runtime dependencies...
==> Checking buildtime dependencies...
==> Retrieving sources...
  -> Downloading aura-1.2.3.4.tar.gz...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100 99115  100 99115    0     0  66012      0  0:00:01  0:00:01 --:--:-- 29312
==> Validating source files with md5sums...
    aura-1.2.3.4.tar.gz ... Passed
==> Extracting sources...
  -> Extracting aura-1.2.3.4.tar.gz with bsdtar
==> Starting build()...

Setup.hs:1:8:
    Could not find module ‘Distribution.Simple’
    Perhaps you haven't installed the "dyn" libraries for package
‘Cabal-1.20.0.0’?
    Use -v to see a list of the files searched for.
==> ERROR: A failure occurred in build().
    Aborting...


aura >>= Would you like to continue anyway? [Y/n] n
aura >>= Building failed.