Bug #20903 Crash when using CREATE TABLE .. SELECT and triggers

Description:
CREATE TABLE IF NOT EXISTS table SELECT crashes the server if table already exists and have a BEFORE INSERT trigger.

How to repeat:
CREATE TABLE t1 (i INT);
CREATE TRIGGER t1_bi BEFORE INSERT ON t1 FOR EACH ROW SET NEW.i = 1;
CREATE TABLE t2 (i INT);
INSERT INTO t2 VALUES (1), (2);
CREATE TABLE IF NOT EXISTS t1 SELECT * FROM t2;
-- Crash happens here

Back trace 5.0.23 Linux Suse 32-bit

Attachment: bt-20903.txt (text/plain), 12.41 KiB.

Thank you for the bug report. Verified as described.

ChangeSet@1.2342, 2006-12-05 15:44:34+03:00, dlenev@mockturtle.local +12 -0
  Proposed patch for bugs:
    #20662 "Infinite loop in CREATE TABLE IF NOT EXISTS ... SELECT
          with locked tables"
    #20903 "Crash when using CREATE TABLE .. SELECT and triggers"
    #24738  "CREATE TABLE ... SELECT is not isolated properly"

http://lists.mysql.com/commits/16454

Setting back to In Progress as this is the same as Bug#20662

Pushed into 5.0.42

Pushed into 5.1.19-beta

Noted in 5.0.42, 5.1.19 changelogs.

CREATE TABLE IF NOT EXISTS ... SELECT caused a server crash if the
target table already existed and had a BEFORE INSERT trigger.