CPANPLUS package adds a perl-cpanplus-dist-arch dependency.

[juster]

For some reason, when creating a package for CPANPLUS, perl-cpanplus-dist-arch is listed as a dependency (version 0.0 to be exact).

This is most likely inside CPANPLUS's source code because C::D::A only translates the dependencies CPANPLUS gives it into pacman packages.

[juster]

CPANPLUS::Dist::Arch is added as a requirement of CPANPLUS when Makefile.PL runs. Makefile.PL creates a Makefile with modules required for certain features. Features are enabled (and modules required) if the running instance of CPANPLUS has certain configuration values set.
(See Makefile.PL:160)

There is a 'dist_type' feature which is enabled if the 'dist_type' config value is set to anything. The 'dist_type' in this case is set to CPANPLUS::Dist::Arch.
(See Selfupdate:95)

If the 'dist_type' feature is "enabled", its value (C::D::A) is added to CPANPLUS's prerequisite modules! Bummmer!

When 'dist_type' is set that means the packager CPANPLUS::Dist::Whatever module is trying to package CPANPLUS. This new CPANPLUS package then has a dependency on CPANPLUS::Dist::Whatever, which of course depends on CPANPLUS to even run! Weird.