A USE_INDEX_MERGE hint causes a server panic

[mrigger]

Consider the following statements:

CREATE TABLE t0(c0 INT, c1 INT, PRIMARY KEY(c1));
CREATE INDEX i0 ON t0(c0);
SELECT /*+ USE_INDEX_MERGE(t0, PRIMARY) */ * FROM t0 WHERE 1 OR t0.c1;

Unexpectedly, the SELECT causes a server panic:

[2020/04/01 21:32:35.184 +02:00] [ERROR] [conn.go:659] ["connection running loop panic"] [conn=5282] [lastSQL="SELECT /*+ USE_INDEX_MERGE(t0, PRIMARY) */ * FROM t0 WHERE 1 OR t0.c1"] [err="runtime error: invalid memory address or nil pointer dereference"] [stack="goroutine 405232527 [running]:\ngit.luolix.top/pingcap/tidb/server.(*clientConn).Run.func1(0x2cfa760, 0xc0498fe150, 0xc0022bf040)\n\t/tidb/server/conn.go:657 +0xee\npanic(0x2680ea0, 0x3db2c30)\n\t/usr/lib/go-1.13/src/runtime/panic.go:679 +0x1b2\ngit.luolix.top/pingcap/tidb/planner/core.finishCopTask(0x2d32de0, 0xc00105a600, 0x2d10060, 0xc0029ae090, 0xc001bb6420, 0x4118509555555556)\n\t/tidb/planner/core/task.go:677 +0xa1\ngit.luolix.top/pingcap/tidb/planner/core.(*DataSource).convertToIndexMergeScan(0xc001cee3c0, 0xc0048083c0, 0xc000a48ac0, 0x1, 0x4, 0xee6098, 0x10)\n\t/tidb/planner/core/find_best_task.go:567 +0x42f\ngit.luolix.top/pingcap/tidb/planner/core.(*DataSource).findBestTask(0xc001cee3c0, 0xc0048083c0, 0x2d100c0, 0x3db4ac0, 0x0, 0x0)\n\t/tidb/planner/core/find_best_task.go:455 +0x968\ngit.luolix.top/pingcap/tidb/planner/core.(*baseLogicalPlan).findBestTask(0xc001a7a5a0, 0xc004808370, 0x0, 0x0, 0x0, 0x0)\n\t/tidb/planner/core/find_best_task.go:179 +0x61f\ngit.luolix.top/pingcap/tidb/planner/core.physicalOptimize(0x2d31ae0, 0xc001a7a580, 0x20a2, 0x2d31ae0, 0xc001a7a580, 0x2d31ae0, 0xc001a7a580)\n\t/tidb/planner/core/optimizer.go:180 +0xb3\ngit.luolix.top/pingcap/tidb/planner/core.DoOptimize(0x2cfa760, 0xc0498fe150, 0x2d32de0, 0xc00105a600, 0x20a2, 0x2d31ae0, 0xc001a7a580, 0x0, 0x0, 0x0, ...)\n\t/tidb/planner/core/optimizer.go:131 +0xa7\ngit.luolix.top/pingcap/tidb/planner.optimize(0x2cfa760, 0xc0498fe150, 0x2d32de0, 0xc00105a600, 0x2cfc2e0, 0xc0024240d0, 0x2d280c0, 0xc0029565d0, 0x0, 0x0, ...)\n\t/tidb/planner/optimize.go:189 +0x5a9\ngit.luolix.top/pingcap/tidb/planner.Optimize(0x2cfa760, 0xc0498fe150, 0x2d32de0, 0xc00105a600, 0x2cfc2e0, 0xc0024240d0, 0x2d280c0, 0xc0029565d0, 0x0, 0x0, ...)\n\t/tidb/planner/optimize.go:63 +0x28f\ngit.luolix.top/pingcap/tidb/executor.(*Compiler).Compile(0xc00060edc8, 0x2cfa760, 0xc0498fe150, 0x2d01ba0, 0xc0024240d0, 0x0, 0x0, 0x0)\n\t/tidb/executor/compiler.go:61 +0x253\ngit.luolix.top/pingcap/tidb/session.(*session).execute(0xc00105a600, 0x2cfa760, 0xc0498fe150, 0xc0553e0e11, 0x45, 0xc02d12ef00, 0x0, 0x0, 0xc00060f178, 0x240dc1a)\n\t/tidb/session/session.go:1138 +0x5cf\ngit.luolix.top/pingcap/tidb/session.(*session).Execute(0xc00105a600, 0x2cfa760, 0xc0498fe150, 0xc0553e0e11, 0x45, 0x0, 0x0, 0x0, 0x0, 0x0)\n\t/tidb/session/session.go:1089 +0xdb\ngit.luolix.top/pingcap/tidb/server.(*TiDBContext).Execute(0xc00d724990, 0x2cfa760, 0xc0498fe150, 0xc0553e0e11, 0x45, 0xf081e1, 0x2a23570, 0xc00060f278, 0xc00060f268, 0xfa8572)\n\t/tidb/server/driver_tidb.go:248 +0x7c\ngit.luolix.top/pingcap/tidb/server.(*clientConn).handleQuery(0xc0022bf040, 0x2cfa760, 0xc0498fe150, 0xc0553e0e11, 0x45, 0x0, 0x0)\n\t/tidb/server/conn.go:1257 +0x91\ngit.luolix.top/pingcap/tidb/server.(*clientConn).dispatch(0xc0022bf040, 0x2cfa760, 0xc0498fe150, 0xc0553e0e11, 0x46, 0x45, 0x0, 0x0)\n\t/tidb/server/conn.go:898 +0x5e2\ngit.luolix.top/pingcap/tidb/server.(*clientConn).Run(0xc0022bf040, 0x2cfa760, 0xc0498fe150)\n\t/tidb/server/conn.go:712 +0x27c\ngit.luolix.top/pingcap/tidb/server.(*Server).onConn(0xc000171a20, 0xc0022bf040)\n\t/tidb/server/server.go:415 +0xaf9\ncreated by github.com/pingcap/tidb/server.(*Server).Run\n\t/tidb/server/server.go:333 +0x709\n"]

Environment:

mysql> SELECT tidb_version();
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version()                                                                                                                                                                                                                                                                                          |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: v4.0.0-beta.2-160-g82529c886
Git Commit Hash: 82529c886cb1cfff7810476a136acf81284bac6e
Git Branch: master
UTC Build Time: 2020-04-01 11:44:27
GoVersion: go1.13.4
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

[XuHuaiyu]

@eurekaka PTAL