rpl.rpl_row_img_eng_noblob failed in buildbot with command "diff_files" failed

rpl.rpl_row_img_eng_noblob 'row,xtradb'  w1 [ fail ]

        Test ended at 2017-10-22 17:24:45

CURRENT_TEST: rpl.rpl_row_img_eng_noblob

mysqltest: In included file "./include/rpl_row_img_general_loop.inc": 

included from /usr/share/mysql/mysql-test/suite/rpl/t/rpl_row_img_eng_noblob.test at line 34:

At line 39: command "diff_files" failed with error: 1  my_errno: 0  errno: -1

The result from queries just before the failure was:

< snip >

UPDATE t SET c1 = '5' WHERE c1 = 1;

UPDATE t SET c4 = '8' WHERE c2 = '4';

UPDATE t SET c1 = '8' WHERE c2 = '4';

UPDATE t SET c2 = '8' WHERE c2 = '4';

UPDATE t SET c3 = '0' WHERE c4 = NULL;

UPDATE t SET c2 = '0' WHERE c4 = '0';

UPDATE t SET c2 = '2' WHERE c4 = '2';

include/rpl_sync.inc

include/diff_tables.inc [server_1:test.t, server_2:test.t, server_3:test.t]

--- /dev/shm/var/1/mysqld.1/data//diff_table-server_1-test-t	2017-10-22 17:24:45.253403230 -0400

+++ /dev/shm/var/1/mysqld.2/data//diff_table-server_2-test-t	2017-10-22 17:24:45.253403230 -0400

@@ -1,6 +1,6 @@

+1	5	1	5

 2	1	2	7

 3	1	3	7

-5	5	1	5

+4	4	4	7

 7	7	7	7

-8	8	4	8

 9	9	9	7

More results from queries before failure can be found in /dev/shm/var/1/log/rpl_row_img_eng_noblob.log