Merge branch '10.6' into 10.7

mysql-test/suite/innodb/r/import_bugs.result

@@ -10,3 +10,11 @@ ALTER TABLE imp_t1 IMPORT TABLESPACE;
 ERROR HY000: Schema mismatch (ROW_FORMAT mismatch)
 DROP TABLE imp_t1, t1;
 SET GLOBAL innodb_checksum_algorithm=@save_innodb_checksum_algorithm;
+#
+# MDEV-27006 Assertion `!lock_trx_has_sys_table_locks(trx)' --echo #	failed in dberr_t row_discard_tablespace_for_mysql
+#		(dict_table_t*, trx_t*)
+CREATE TABLE t1 (c INT KEY) ENGINE=INNODB;
+CREATE TABLE t2 (c INT KEY,FOREIGN KEY(c) REFERENCES t1 (c)) ENGINE=INNODB;
+ALTER TABLE t1 DISCARD TABLESPACE;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
+DROP TABLE t2, t1;

mysql-test/suite/innodb/t/import_bugs.test

@@ -18,3 +18,12 @@ DROP TABLE imp_t1, t1;
 --remove_file $datadir/test/imp_t1.ibd
 
 SET GLOBAL innodb_checksum_algorithm=@save_innodb_checksum_algorithm;
+
+--echo #
+--echo # MDEV-27006 Assertion `!lock_trx_has_sys_table_locks(trx)' --echo #	failed in dberr_t row_discard_tablespace_for_mysql
+--echo #		(dict_table_t*, trx_t*)
+CREATE TABLE t1 (c INT KEY) ENGINE=INNODB;
+CREATE TABLE t2 (c INT KEY,FOREIGN KEY(c) REFERENCES t1 (c)) ENGINE=INNODB;
+--error ER_ROW_IS_REFERENCED_2
+ALTER TABLE t1 DISCARD TABLESPACE;
+DROP TABLE t2, t1;

storage/innobase/fsp/fsp0fsp.cc

@@ -1709,18 +1709,7 @@ fseg_create(fil_space_t *space, ulint byte_offset, mtr_t *mtr,
 	mtr->x_lock_space(space);
 	ut_d(space->modify_check(*mtr));
 
-	if (block) {
-		ut_ad(block->page.id().space() == space->id);
-
-		if (!space->full_crc32()) {
-			fil_block_check_type(*block, block->page.id()
-					     == page_id_t(TRX_SYS_SPACE,
-							  TRX_SYS_PAGE_NO)
-					     ? FIL_PAGE_TYPE_TRX_SYS
-					     : FIL_PAGE_TYPE_SYS,
-					     mtr);
-		}
-	}
+	ut_ad(!block || block->page.id().space() == space->id);
 
 	if (!has_done_reservation
 	    && !fsp_reserve_free_extents(&n_reserved, space, 2,

storage/innobase/row/row0mysql.cc

@@ -2495,6 +2495,7 @@ dberr_t row_discard_tablespace_for_mysql(dict_table_t *table, trx_t *trx)
         fts_optimize_add_table(table);
       }
       trx->rollback();
+      row_mysql_unlock_data_dictionary(trx);
       return err;
     }
   }
@@ -2508,10 +2509,7 @@ dberr_t row_discard_tablespace_for_mysql(dict_table_t *table, trx_t *trx)
 
   err= row_discard_tablespace_foreign_key_checks(trx, table);
   if (err != DB_SUCCESS)
-  {
-    row_mysql_unlock_data_dictionary(trx);
     goto rollback;
-  }
 
   /* Note: The following cannot be rolled back. Rollback would see the
   UPDATE of SYS_INDEXES.TABLE_ID as two operations: DELETE and INSERT.

storage/myisam/mi_delete.c

@@ -767,6 +767,10 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
 	  returns how many chars was removed or 0 on error
 	*/
 
+#if defined(_MSC_VER) && defined(_M_X64) && _MSC_VER >= 1930
+#pragma optimize("g", off)
+#endif
+
 static uint remove_key(MI_KEYDEF *keyinfo, uint nod_flag,
 		       uchar *keypos,	/* Where key starts */
 		       uchar *lastkey,	/* key to be removed */
@@ -891,3 +895,7 @@ static uint remove_key(MI_KEYDEF *keyinfo, uint nod_flag,
 	(uint) (page_end-start-s_length));
   DBUG_RETURN((uint) s_length);
 } /* remove_key */
+
+#if defined(_MSC_VER) && defined(_M_X64) && _MSC_VER >= 1930
+#pragma optimize("",on)
+#endif