MDEV-4277: Crash inside mi_killed_in_mariadb() with myisammrg

- Set MI_INFO::external_ref for MyISAM tables that are parts of myisamMRG table.

1 files changed, 35 insertions, 0 deletions

diff --git a/mysql-test/t/merge.test b/mysql-test/t/merge.test
index eecf892869f..abb7c3c7da2 100644
--- a/mysql-test/t/merge.test
+++ b/mysql-test/t/merge.test
@@ -1865,6 +1865,41 @@ DROP TABLE t1, t2, t3, m1;
 
 --echo End of 5.1 tests
 
+--echo # 
+--echo # MDEV-4277: Crash inside mi_killed_in_mariadb() with myisammrg
+--echo # 
+create table t1 (a int);
+insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+
+create table t2 ( i int ) engine=myisam;
+insert into t2 values (1),(2);
+
+create table t3 (a int, b int, filler char(100), key(a), key(b)) engine=myisam;
+create table t4 like t3;
+insert into t3 
+  select A.a+10*B.a+100*C.a, 
+         A.a+10*B.a+100*C.a,
+         'filler-data-FILLER-DATA-qqq' 
+  from t1 A, t1 B, t1 C where C.a < 5;
+insert into t4
+  select A.a+10*B.a+100*C.a, 
+         A.a+10*B.a+100*C.a,
+         'filler-data-FILLER-DATA-qqq' 
+  from t1 A, t1 B, t1 C where C.a >= 5;
+
+create table t5 like t3; 
+alter table t5 engine=merge;
+alter table t5 union(t3, t4);
+
+update t5 set b=999, a=999 where b>950;
+
+explain 
+select * from t2, t5 where t5.a=999 and t5.b=999;
+select * from t2, t5 where t5.a=999 and t5.b=999;
+
+drop table t5;
+drop table t1,t2,t3,t4;
+
 --disable_result_log
 --disable_query_log
 eval set global storage_engine=$default;