using GHC for dependency generation, a couple of questions

http://www.haskell.org/ghc/docs/latest/html/users_guide/separate-compilation.html#makefile-dependencies

Recently, I stumbled on -v2 in combination with --make or -M,
which produces nice module-based output instead of the file-based
makefile dependencies of -M, but have run into a couple of :

1. --make can't be used with -fno-code, and -M always
    generates a file, so is this the best one can do:

    ghc -M -v2 -optdep-f -optdep depend Main.hs
    ?
    It would be nice to have the dry-run option (isn't that -fno-code?)
    work with all commands that produce useful stdout information
    (including --make -v2).

2. I can't seem to figure out what --include-pkg-deps does?
    In a way, it seems to be always on, since package imports
    are always listed in the -v2 output.

Claus