HEADS-UP: Deprecation of legacy (v3) password database support

[Ed Maste]

FreeBSD password databases (/etc/pwd.db, /etc/spwd.db) can contain
records in one or both of two versions:
 * v3, a legacy architecture-dependent format
 * v4, the current architecture- and endian-independent format

When v4 support was added in 2003 (r113596) pwd_mkdb emitted both v3 and
v4 records in the output database.  In 2015 r283981 added a -l option to
control the emission of legacy v3 records; by default only v4 records
are emitted.

r283981's commit message states:

    The -l, -B and -L options are considered deprecated and will be
    removed in FreeBSD 12.0 release.

I'd expect little impact if the -l, -B and -L options are removed, as
r113596 is included in FreeBSD 5.1 and later.  If legacy support is
removed then software built on FreeBSD 5.0 or earlier will no longer be
able to make use of password file data (via getpwent, getpwnam, etc.).
Such software would still function inside of a jail that has a v3
password database, of course.

Is anyone using pwd_mkdb's -l option and relying on legacy password
database files in a non-jailed context?