As discussed on IRC, notmuch segfaults with 1.3.1 but not with 1.2.5 on
notmuch-new:

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff75a5367 in Xapian::TermIterator::skip_to(std::string const&) ()
from /usr/lib64/libxapian-1.3.so.1
(gdb) bt
#0  0x00007ffff75a5367 in Xapian::TermIterator::skip_to(std::string const&)
() from /usr/lib64/libxapian-1.3.so.1
#1  0x00007ffff7decaa5 in _notmuch_message_get_term(_notmuch_message*,
Xapian::TermIterator&, Xapian::TermIterator&, char const*) () from
/usr/lib64/libnotmuch.so.3
#2  0x00007ffff7ded1fb in
_notmuch_message_ensure_metadata(_notmuch_message*) () from
/usr/lib64/libnotmuch.so.3
#3  0x00007ffff7ded535 in notmuch_message_get_message_id () from
/usr/lib64/libnotmuch.so.3
#4  0x00007ffff7de9c11 in notmuch_database_add_message () from
/usr/lib64/libnotmuch.so.3
#5  0x000000000040c610 in add_files ()
#6  0x000000000040cfbf in notmuch_new_command ()
#7  0x0000000000407a1b in main ()

This occurs irrespective of the state of the database or the message being
added.