can't load .so/.DLL - undefined symbol

[Henning Thielemann]

Am 17.03.2014 15:33, schrieb Henning Thielemann:
> Am 17.03.2014 10:22, schrieb Simon Marlow:
>> package.  Perhaps you have a copy of that module on the search path
>> somewhere, or inside the alsa-seq package?
>
> This would confirm how I understood the linker message. Then I guess
> that compiling all packages at once in a single build dir with cabal was
> the problem. The command line was like:
>
> $ cabal install --builddir=/tmp/dist --with-ghc=ghc7.8.0.20140228 poll
> alsa-seq pkg1 pkg2 pkg3 ...
>
> After compiling the packages separately the problem has gone.

I think I know what the problem was: 'poll' uses HSC as preprocessor, 
thus preprocessed files were stored in "dist". This way the preprocessed 
source files were available to GHC when compiling 'alsa' and thus it was 
compiled again, but not registered in the 'alsa' package.