Package variant defined in manifest not visible by Guix

[Philippe SWARTVAGHER]

Hello,

I'm trying to use a manifest file to define a package variant which adds
an option to the configure phase:

```

(use-modules (inria storm))

(define starpu-maxnodes1
  (package
    (inherit starpu)
    (arguments
      (substitute-keyword-arguments (package-arguments starpu)
                                    ((#:configure-flags flags '())
                                     `(cons "--enable-maxnodes=1"
,flags))))))

```

When I'm trying to build this variant, guix can't find it:

```

% guix build -c 2 -m starpu-maxnodes1.scm starpu-maxnodes1
guix build: erreur : starpu-maxnodes1 : paquet inconnu

```

I don't see what I'm doing wrong. Any idea ?

Just if you want to try these exact commands, StarPU is a package
defined in this channel:

```

(channel
        (name 'guix-hpc)
        (url "https://gitlab.inria.fr/guix-hpc/guix-hpc.git";)
        (commit
          "fa8cc70bc428c08a625a533f778537314be64ce7"))

```

(I didn't subscribe to help-guix mailing list, so please keep me as
recipient of your answers.)

-- 
Philippe SWARTVAGHER

PhD Student
TADaaM team, Inria Bordeaux Sud-Ouest