Merge bk-internal.mysql.com:/home/bk/mysql-3.23

into mashka.mysql.fi:/home/my/mysql-3.23

configure.in

@@ -4,7 +4,7 @@ dnl Process this file with autoconf to produce a configure script.
 AC_INIT(sql/mysqld.cc)
 AC_CANONICAL_SYSTEM
 # The Docs Makefile.am parses this line!
-AM_INIT_AUTOMAKE(mysql, 3.23.56)
+AM_INIT_AUTOMAKE(mysql, 3.23.57)
 AM_CONFIG_HEADER(config.h)
 
 PROTOCOL_VERSION=10

innobase/row/row0sel.c

@@ -2115,19 +2115,14 @@ row_sel_store_mysql_rec(
 				extern_field_heap = NULL;
  			}
 		} else {
-			/* MySQL sometimes seems to copy the 'data'
-			pointed to by a BLOB field even if the field
-			has been marked to contain the SQL NULL value.
-			This caused seg faults reported by two users.
-			Set the BLOB length to 0 and the data pointer
-			to NULL to avoid a seg fault. */
-
-			if (templ->type == DATA_BLOB) {
-				row_sel_field_store_in_mysql_format(
-				mysql_rec + templ->mysql_col_offset,
-				templ->mysql_col_len, NULL,
-				0, templ->type, templ->is_unsigned);
-			}
+		        /* MySQL seems to assume the field for an SQL NULL
+		        value is set to zero. Not taking this into account
+		        caused seg faults with NULL BLOB fields, and
+		        bug number 154 in the MySQL bug database: GROUP BY
+		        and DISTINCT could treat NULL values inequal. */
+
+		        memset(mysql_rec + templ->mysql_col_offset, '\0',
+			       templ->mysql_col_len);
 
 			if (!templ->mysql_null_bit_mask) {
 				fprintf(stderr,