LOCK+modify+OPTIMIZE bugfix

Docs/manual.texi

@@ -46929,6 +46929,9 @@ not yet 100% confident in this code.
 @appendixsubsec Changes in release 3.23.53
 @itemize @bullet
 @item
+Fixed a bug that @code{OPTIMIZE} of locked and modified MyISAM table,
+reported table corruption.
+@item
 Fixed a @code{BDB}-related @code{ALTER TABLE} bug with dropping a column
 and shutting down immediately thereafter.
 @item

mysql-test/r/myisam.result

@@ -36,3 +36,5 @@ table	type	possible_keys	key	key_len	ref	rows	Extra
 t1	ALL	NULL	NULL	NULL	NULL	4	
 table	type	possible_keys	key	key_len	ref	rows	Extra
 t1	ALL	NULL	NULL	NULL	NULL	4	
+Table	Op	Msg_type	Msg_text
+test.t1	optimize	status	OK

mysql-test/t/myisam.test

@@ -64,3 +64,14 @@ explain select a,b from t1 order by b;
 explain select a,b from t1;
 explain select a,b,c from t1;
 drop table t1;
+
+#
+# Test of OPTIMIZE of locked and modified tables
+#
+CREATE TABLE t1 (a INT);
+INSERT INTO  t1 VALUES (1), (2), (3);
+LOCK TABLES t1 WRITE;
+INSERT INTO  t1 VALUES (1), (2), (3);
+OPTIMIZE TABLE t1;
+DROP TABLE t1;
+

sql/ha_myisam.cc

@@ -561,6 +561,7 @@ int ha_myisam::repair(THD *thd, MI_CHECK &param, bool optimize)
   }
 
   if (!optimize ||
+      memcmp(file->state, & share->state.state, sizeof(MI_STATUS_INFO)) ||
       ((file->state->del || share->state.split != file->state->records) &&
        (!param.opt_rep_quick ||
 	!(share->state.changed & STATE_NOT_OPTIMIZED_KEYS))))