[Haskell-cafe] Haskell-Cafe Digest, Vol 121, Issue 8

[Gregory Guthrie]

> Hi all,
> 
> On behalf of the cabal maintainers and contributors I'm proud to announce the Cabal (and
> cabal-install) 1.18.0 release. To install run
> 
>     cabal update && cabal install Cabal-1.18.0 cabal-install-1.18.0
> 
> With 854 commits since the last release there are two many improvements and bug fixes to
> list them here, but two highlights are:
> 
>  * Hermetic builds using sandboxes. This should reduce the number of "dependency hell" and
> broken package DB problems.
> 
[>>]
 I was quite happy to hear of the new cabal - and the chance to escape the various mazes of cabal-dependency problems.
But I seem to have a bootstrapping problem, the new cabal won't install to help me get out of its messes!

I tried to install what I thought were its complaints (below), and they seemed OK - any hints?

The key problem seems to be:
" mtl-2.1.2-5337caef659244e51e2f5fb2e944d97f is shadowed by package mtl-2.1.2-678980f6077e9f83a86186556aa2a425"
Not sure how this happened, or how to remedy it.

Cabal FAQ says to unregister the user database version, but that notes that it would break about 20+ other packages, but do it anyway. So yes, I did and now have a bigger mess it seems.

Now mtl install gives:
Building mtl-2.1.2...
Preprocessing library mtl-2.1.2...
    Bad interface file: E:\Plang\Haskell Platform\lib\extralibs\transformers-0.3.0.0\ghc-7.4.2\Control\Monad\Trans\Error.hi
        mismatched interface file versions (wanted "7063", got "7042")
Failed to install mtl-2.1.2
cabal: Error: some packages failed to install:
mtl-2.1.2 failed during the building phase. The exception was: ExitFailure 1

I am reluctant to do a clean restart install, since it was so much trouble building some packages like wx and other graphics .dll packages.

Argh...
---------------------------------------------------------------------------------------------------
C:\Users\guthrie>cabal update
Downloading the latest package list from hackage.haskell.org
Note: there is a new version of cabal-install available.
To upgrade, run: cabal install cabal-install

C:\Users\guthrie>cabal install cabal-install
Resolving dependencies...
Downloading Cabal-1.18.0...
[ 1 of 70] Compiling Distribution.PackageDescription.Utils
 ...
[70 of 70] Compiling Main             ( C:\Users\guthrie\AppData\Local\Temp\Cabal-1.18.0-13108\Cabal-1.18.0\Setup.hs, C:\Users\guthrie\AppData\Local\Temp\Cabal-1.18.0-13108\Cabal-1.18.0\dist\setup\Main.o )
Linking C:\Users\guthrie\AppData\Local\Temp\Cabal-1.18.0-13108\Cabal-1.18.0\dist\setup\setup.exe ...
Configuring Cabal-1.18.0...
Building Cabal-1.18.0...
Preprocessing library Cabal-1.18.0...
[ 1 of 72] Compiling Paths_Cabal      ...

Distribution\Version.hs:125:1: Warning:
    Orphan instance: instance Data Version
In-place registering Cabal-1.18.0...
Installing library in C:\Users\guthrie\AppData\Roaming\cabal\i386-windows-ghc-7.6.3\Cabal-1.18.0
Registering Cabal-1.18.0...
Installed Cabal-1.18.0
Downloading cabal-install-1.18.0...
Configuring cabal-install-1.18.0...
Warning: This package indirectly depends on multiple versions of the same package. This is highly likely to cause a compile failure.
...
package mtl-2.1.2 requires transformers-0.3.0.0
package mtl-2.1.2 requires transformers-0.3.0.0
Building cabal-install-1.18.0...
Preprocessing executable 'cabal' for cabal-install-1.18.0...
<command line>: cannot satisfy -package-id mtl-2.1.2-5337caef659244e51e2f5fb2e944d97f:
    mtl-2.1.2-5337caef659244e51e2f5fb2e944d97f is shadowed by package mtl-2.1.2-678980f6077e9f83a86186556aa2a425
    (use -v for more information)
Failed to install cabal-install-1.18.0
cabal: Error: some packages failed to install:
cabal-install-1.18.0 failed during the building phase. The exception was:ExitFailure 1

C:\Users\guthrie>cabal install mtl
Resolving dependencies...
All the requested packages are already installed: mtl-2.1.2
Use --reinstall if you want to reinstall anyway.

C:\Users\guthrie>cabal install transformers
Resolving dependencies...
All the requested packages are already installed: transformers-0.3.0.0
Use --reinstall if you want to reinstall anyway.