[Dune] conflicting defines for SuperLU ?

[Christian Engwer]

> I'll defer to others to answer authoritatively, but I believe that's
> more or less as intended by the design.  The reasoning is, I believe,
> that the SuperLU feature should not be automatically enabled when it's
> found on a particular computer system.  In other words, the developer
> using the ISTL must specifically enable SuperLU by including the
> $(SUPERLU_CPPFLAGS) in the program's (or library's) _CPPFLAGS primary
> (or globally using the AM_CPPFLAGS primary).
> 
> The $(SUPERLU_CPPFLAGS) specify, among other things such as include
> paths, the string "-DENABLE_SUPERLU=1" on systems providing SuperLU.

You are absolutely right!

Christian