Problem building devel/py-boost with Python 3.7

[Marc Baudoin <babafou%babafou.eu.org@localhost>]

Hi,

While trying to upgrade finance/ledger to version 3.2.0, which
works with Python 3 now, I noticed devel/py-boost doesn't build
anymore:

=> Generating post-install file lists
pkg_create: can't stat `/usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.a'
pkg_create: can't stat `/usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so'
pkg_create: can't stat `/usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so.1'
pkg_create: can't stat `/usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so.1.72'
pkg_create: can't stat `/usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so.1.72.0'
=> Checking file-check results for py37-boost-1.72.0
ERROR: ************************************************************
ERROR: The following files are in the PLIST but not in /usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg:
ERROR:         /usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.a
ERROR:         /usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so
ERROR:         /usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so.1
ERROR:         /usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so.1.72
ERROR:         /usr/pkgsrc/devel/py-boost/work/.destdir/usr/pkg/lib/libboost_numpy37.so.1.72.0
*** Error code 1

Indeed, PLIST contains:

lib/libboost_numpy${PYVER}.a
lib/libboost_numpy${PYVER}.so
lib/libboost_numpy${PYVER}.so.1
lib/libboost_numpy${PYVER}.so.1.72
lib/libboost_numpy${PYVER}.so.${PKGVERSION}
lib/libboost_python${PYVER}.a
lib/libboost_python${PYVER}.so
lib/libboost_python${PYVER}.so.1
lib/libboost_python${PYVER}.so.1.72
lib/libboost_python${PYVER}.so.${PKGVERSION}

but devel/py-boost/work/.destdir/usr/pkg/lib only contains:

libboost_python37.a
libboost_python37.so@
libboost_python37.so.1@
libboost_python37.so.1.72@
libboost_python37.so.1.72.0*

Did I miss something or is there a problem with this package (it
built fine in January with Python 2, I use it as a dependency for
the previous version of ledger)?