Raghav Gururajan via Guix-patches via schreef op do 02-09-2021 om 10:12 [-0400]:
> +        "-Dgtk_doc=true"

Only when compiling natively.  At least for json-glib,
setting Dgtk_doc=true will cause gtk-doc-scangobj to try to
execute a cross-compiled binary, which won't work, see
<https://issues.guix.gnu.org/50201#33>.

Though possibly not all packages with gtk_doc use gtk-doc-scangobj,
so leaving this for later, when all dependencies of gtk are actually
cross-compilable, might be reasonable.

Greetings,
Maxime