Bug#812299: FTBFS: Ambiguous occurrence `ReifiedMonoid'

[Martin Michlmayr]

Package: haskell-lens
Version: 4.12.3-2
Severity: serious

haskell-lens fails to build in unstable:

> sbuild (Debian sbuild) 0.67.0 (26 Dec 2015) on dl580gen9-02.hlinux
...
> [18 of 81] Compiling Control.Lens.Internal.Fold ( src/Control/Lens/Internal/Fold.hs, dist-ghc/build/Control/Lens/Internal/Fold.o )
> 
> src/Control/Lens/Internal/Fold.hs:223:21:
>     Ambiguous occurrence `ReifiedMonoid'
>     It could refer to either `Control.Lens.Internal.Fold.ReifiedMonoid',
>                              defined at src/Control/Lens/Internal/Fold.hs:221:1
>                           or `Data.Reflection.ReifiedMonoid',
>                              imported from `Data.Reflection' at src/Control/Lens/Internal/Fold.hs:39:1-22
> 
> src/Control/Lens/Internal/Fold.hs:224:49:
>     Ambiguous occurrence `reifiedMappend'
>     It could refer to either `Control.Lens.Internal.Fold.reifiedMappend',
>                              defined at src/Control/Lens/Internal/Fold.hs:221:40
>                           or `Data.Reflection.reifiedMappend',
>                              imported from `Data.Reflection' at src/Control/Lens/Internal/Fold.hs:39:1-22
> 
> src/Control/Lens/Internal/Fold.hs:225:49:
>     Ambiguous occurrence `reifiedMempty'
>     It could refer to either `Control.Lens.Internal.Fold.reifiedMempty',
>                              defined at src/Control/Lens/Internal/Fold.hs:221:71
>                           or `Data.Reflection.reifiedMempty',
>                              imported from `Data.Reflection' at src/Control/Lens/Internal/Fold.hs:39:1-22
> 
> src/Control/Lens/Internal/Fold.hs:235:58:
>     Ambiguous occurrence `ReifiedMonoid'
>     It could refer to either `Control.Lens.Internal.Fold.ReifiedMonoid',
>                              defined at src/Control/Lens/Internal/Fold.hs:221:1
>                           or `Data.Reflection.ReifiedMonoid',
>                              imported from `Data.Reflection' at src/Control/Lens/Internal/Fold.hs:39:1-22
> 
> src/Control/Lens/Internal/Fold.hs:236:29:
>     Ambiguous occurrence `ReifiedMonoid'
>     It could refer to either `Control.Lens.Internal.Fold.ReifiedMonoid',
>                              defined at src/Control/Lens/Internal/Fold.hs:221:24
>                           or `Data.Reflection.ReifiedMonoid',
>                              imported from `Data.Reflection' at src/Control/Lens/Internal/Fold.hs:39:1-22
> /usr/share/cdbs/1/class/hlibrary.mk:147: recipe for target 'build-ghc-stamp' failed
> make: *** [build-ghc-stamp] Error 1
> dpkg-buildpackage: error: debian/rules build gave error exit status 2

-- 
Martin Michlmayr
Linux for HPE Helion, Hewlett Packard Enterprise