Guillaume Le Vaillant schreef op zo 10-04-2022 om 14:23 [+0000]:
> It looks like the problem comes from a gexp in the builder. There's
> a gexp inside another gexp, but I don't know if that's the problem:
> 
> --8<---------------cut here---------------start------------->8---
> #:phases (modify-phases #<gexp (modify-phases #<gexp-input #<gexp ...

Suggestion:

Replace

     (substitute-keyword-arguments (package-arguments llvm)
       ((#:phases phases)
        `(modify-phases ,phases
           (delete 'install-opt-viewer)))))))

by

     (substitute-keyword-arguments (package-arguments llvm)
       ((#:phases phases)
        #~(modify-phases #$phases
            (delete 'install-opt-viewer)))))))

in llvm-3.9.1.

Greetings,
Maxime.