Sporadic failure in innodb.innodb_corrupt_bit on P8

innodb.innodb_corrupt_bit 'xtradb'       w2 [ fail ]

        Test ended at 2016-01-15 04:07:57

CURRENT_TEST: innodb.innodb_corrupt_bit

mysqltest: At line 79: query 'INSERT INTO corrupt_bit_test_ā VALUES(13000,'x',1,1)' failed: 1062: Duplicate entry '1-x' for key 'idxā'

The result from queries just before the failure was:

< snip >

@@unique_checks

0

select @@innodb_change_buffering_debug;

@@innodb_change_buffering_debug

1

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+1,z+1 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+10,z+10 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+20,z+20 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+50,z+50 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+100,z+100 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+200,z+200 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+400,z+400 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+800,z+800 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+1600,z+1600 FROM corrupt_bit_test_ā;

INSERT INTO corrupt_bit_test_ā SELECT 0,b,c+4000,z+4000 FROM corrupt_bit_test_ā;

select count(*) from corrupt_bit_test_ā;

count(*)

1024

CREATE INDEX idx3 ON corrupt_bit_test_ā(b, c);

INSERT INTO corrupt_bit_test_ā VALUES(13000,'x',1,1);