Fixed lock sorting and lock check issues with thr_lock that caused warnings...

Fixed lock sorting and lock check issues with thr_lock that caused warnings when running test suite.
Safety check that could cause core dump when doing create table with virtual column.

mysql-test/mysql-test-run.pl:
  Show also warnings from thr_lock (which starts with just Warning, not Warning:)
mysql-test/r/lock.result:
  Added test that showed not relevant warning when using table locks.
mysql-test/t/lock.test:
  Added test that showed not relevant warning when using table locks.
mysys/thr_lock.c:
  Fixed sorting of locks.
  (Old sort code didn't handle case where TL_WRITE_CONCURRENT_INSERT must be sorted before TL_WRITE)
  Added more information to check_locks warning output.
  Fixed wrong testing of multiple different write locks for same table.
sql/item_cmpfunc.cc:
  Safety check that could cause core dump when doing create table with virtual column.

mysql-test/mysql-test-run.pl

@@ -4383,7 +4383,7 @@ sub extract_warning_lines ($) {
 
   my @patterns =
     (
-     qr/^Warning:|mysqld: Warning|\[Warning\]/,
+     qr/^Warning|mysqld: Warning|\[Warning\]/,
      qr/^Error:|\[ERROR\]/,
      qr/^==\d+==\s+\S/, # valgrind errors
      qr/InnoDB: Warning|InnoDB: Error/,

mysql-test/r/lock.result

@@ -194,3 +194,13 @@ ERROR HY000: Table 't2' was locked with a READ lock and can't be updated
 UNLOCK TABLES;
 DROP TABLE t1,t2;
 End of 5.1 tests.
+create table t1 (a int) engine=myisam;
+lock tables t1 write concurrent, t1 as t2 read;
+lock tables t1 read local;
+unlock tables;
+unlock tables;
+lock tables t1 read local;
+lock tables t1 write concurrent, t1 as t2 read;
+unlock tables;
+unlock tables;
+drop table t1;

mysql-test/t/lock.test

@@ -245,3 +245,28 @@ UNLOCK TABLES;
 DROP TABLE t1,t2;
 
 --echo End of 5.1 tests.
+
+#
+# Test concurrent lock and read locks
+# This gave a warning:
+# Warning at 'read lock with old write lock' for lock: 5:
+# Found lock of type 8 that is write and read locked. Read_no_write_count: 1
+#
+create table t1 (a int) engine=myisam;
+lock tables t1 write concurrent, t1 as t2 read;
+connect (con1,localhost,root,,);
+connection con1;
+lock tables t1 read local;
+unlock tables;
+connection default;
+unlock tables;
+connection con1;
+lock tables t1 read local;
+connection default;
+lock tables t1 write concurrent, t1 as t2 read;
+unlock tables;
+connection con1;
+unlock tables;
+disconnect con1;
+connection default;
+drop table t1;

sql/item_cmpfunc.cc

@@ -412,7 +412,8 @@ static bool convert_constant_item(THD *thd, Item_field *field_item,
     LINT_INIT(old_maps[0]);
     LINT_INIT(old_maps[1]);
 
-    if (table)
+    /* table->read_set may not be set if we come here from a CREATE TABLE */
+    if (table && table->read_set)
       dbug_tmp_use_all_columns(table, old_maps, 
                                table->read_set, table->write_set);
     /* For comparison purposes allow invalid dates like 2000-01-32 */
@@ -448,7 +449,7 @@ static bool convert_constant_item(THD *thd, Item_field *field_item,
     }
     thd->variables.sql_mode= orig_sql_mode;
     thd->count_cuted_fields= orig_count_cuted_fields;
-    if (table)
+    if (table && table->read_set)
       dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_maps);
   }
   return result;