buildlink issue with libarchive and xz

[Nicolas Thauvin <nico%orgrim.net@localhost>]

Hello,

I have the buildlink phase failing when building pkgin from
pkgsrc-current (cvs up'ed today) on NetBSD 5.1 i386:

# make
=> Bootstrap dependency digest>=20010302: found digest-20080510
===> Skipping vulnerability checks.
WARNING: No /var/db/pkg/pkg-vulnerabilities file found.
WARNING: To fix run: `/usr/pkg/sbin/pkg_admin -K /var/db/pkg
fetch-pkg-vulnerabilities'.
=> Checksum SHA1 OK for pkgin-0.5.2.1.tar.gz
=> Checksum RMD160 OK for pkgin-0.5.2.1.tar.gz
===> Installing dependencies for pkgin-0.5.2.1nb1
=> Full dependency pkg_install>=20110215: found pkg_install-20110805
===> Overriding tools for pkgin-0.5.2.1nb1
===> Extracting for pkgin-0.5.2.1nb1
===> Patching for pkgin-0.5.2.1nb1
===> Creating toolchain wrappers for pkgin-0.5.2.1nb1
ERROR: xz>=5.0.0 is not installed; can't buildlink files.
*** Error code 1

Stop.
make: stopped in /usr/pkgsrc/pkgtools/pkgin
*** Error code 1

Stop.
make: stopped in /usr/pkgsrc/pkgtools/pkgin


I think it comes from the recent addition of a dependency on
archivers/xz to the buildlink file of libarchive being used by pkgin.

libarchive comes from the builtin on the system, but xz is not
available as a builtin :

# make show-var VARNAME=USE_BUILTIN.libarchive
yes
# make show-var VARNAME=USE_BUILTIN.xz        
no

I don't understand why xz is not installed from pkgsrc as a build
dependencies here.

Regards,
Nicolas