[PATCH] lib: work around xapian bug with get_mset(0,0, x)

[David Bremner]

David Bremner <david at tethera.net> writes:

> At least Fedora28 triggers this Xapian bug due to some toolchain change .
>
>    https://bugzilla.redhat.com/show_bug.cgi?id=1546162
>
> The underlying bug is fixed in xapian commit f92e2a936c1592, and
> should be fixed in Xapian 1.4.6

pushed to origin and master

d