Fixed bug in full join with many NULL fields.

Build-tools/Do-compile

@@ -108,7 +108,7 @@ $|=1;
 select STDOUT;
 $|=1;
 
-safe_cd("$host");
+safe_cd($host);
 if ($opt_stage == 0 && ! $opt_use_old_distribution)
 {
   safe_system("gunzip < $opt_distribution | $tar xf -");
@@ -118,6 +118,7 @@ if ($opt_stage == 0 && ! $opt_use_old_distribution)
   system("touch timestamp; find . -newer timestamp -print | xargs touch; rm -f timestamp");
   sleep(2);
   # Ensure that files we don't want to rebuild are newer than other files
+  safe_cd($ver);
   foreach $name ("configure",
 		 "Docs/include.texi",
 		 "Docs/*.html", "Docs/manual.txt", "Docs/mysql.info",
@@ -125,9 +126,11 @@ if ($opt_stage == 0 && ! $opt_use_old_distribution)
   {
     system("touch $name");
   }
+  # Fix some file modes in BDB tables that makes life harder.
+  system("chmod -R u+rw .");
 }
 
-safe_cd($ver);
+safe_cd("$pwd/$host/$ver");
 if ($opt_stage <= 1)
 {
   $opt_config_options.=" --with-low-memory" if ($opt_with_low_memory);

Docs/manual.texi

@@ -46833,6 +46833,7 @@ users use this code as the rest of the code and because of this we are
 not yet 100% confident in this code.
 
 @menu
+* News-3.23.49::                
 * News-3.23.48::                Changes in release 3.23.48
 * News-3.23.47::                Changes in release 3.23.47
 * News-3.23.46::                Changes in release 3.23.46
@@ -46885,7 +46886,15 @@ not yet 100% confident in this code.
 * News-3.23.0::                 Changes in release 3.23.0
 @end menu
 
-@node News-3.23.48, News-3.23.47, News-3.23.x, News-3.23.x
+@node News-3.23.49, News-3.23.48, News-3.23.x, News-3.23.x
+@appendixsubsec Changes in release 3.23.49
+@itemize @bullet
+@item
+Fixed unlikely caching bug when doing a join without keys. In this case
+the last used field for a table always returned @code{NULL}.
+@end itemize
+
+@node News-3.23.48, News-3.23.47, News-3.23.49, News-3.23.x
 @appendixsubsec Changes in release 3.23.48
 @itemize @bullet
 @item

mysql-test/r/join.result

@@ -31,3 +31,6 @@ COUNT(t1.Title)
 1
 COUNT(t1.Title)
 1
+t1_id	t2_id	type	cost_unit	min_value	max_value	t3_id	item_id	id	name
+22	1	Percent	Cost	100	-1	6	291	1	s1
+23	1	Percent	Cost	100	-1	21	291	1	s1

mysql-test/t/join.test

@@ -194,3 +194,27 @@ t3.Contractor_ID = '999999'  OR
 t3.Contractor_ID = '1') AND 
 t3.CanRead='1' AND t3.Active='1';
 drop table t1,t2,t3;
+
+#
+# Bug when doing full join and NULL fields.
+#
+
+CREATE TABLE t1 (
+  t1_id int(11) default NULL,
+  t2_id int(11) default NULL,
+  type enum('Cost','Percent') default NULL,
+  cost_unit enum('Cost','Unit') default NULL,
+  min_value double default NULL,
+  max_value double default NULL,
+  t3_id int(11) default NULL,
+  item_id int(11) default NULL
+) TYPE=MyISAM;
+INSERT INTO t1 VALUES (12,5,'Percent','Cost',-1,0,-1,-1),(14,4,'Percent','Cost',-1,0,-1,-1),(18,5,'Percent','Cost',-1,0,-1,-1),(19,4,'Percent','Cost',-1,0,-1,-1),(20,5,'Percent','Cost',100,-1,22,291),(21,5,'Percent','Cost',100,-1,18,291),(22,1,'Percent','Cost',100,-1,6,291),(23,1,'Percent','Cost',100,-1,21,291),(24,1,'Percent','Cost',100,-1,9,291),(25,1,'Percent','Cost',100,-1,4,291),(26,1,'Percent','Cost',100,-1,20,291),(27,4,'Percent','Cost',100,-1,7,202),(28,1,'Percent','Cost',50,-1,-1,137),(29,2,'Percent','Cost',100,-1,4,354),(30,2,'Percent','Cost',100,-1,9,137),(93,2,'Cost','Cost',-1,10000000,-1,-1);
+CREATE TABLE t2 (
+  id int(10) unsigned NOT NULL auto_increment,
+  name varchar(255) default NULL,
+  PRIMARY KEY  (id)
+) TYPE=MyISAM;
+INSERT INTO t2 VALUES (1,'s1'),(2,'s2'),(3,'s3'),(4,'s4'),(5,'s5');
+select t1.*, t2.*  from t1, t2 where t2.id=t1.t2_id limit 2;
+drop table t1,t2;

sql/sql_select.cc

@@ -5636,10 +5636,10 @@ SORT_FIELD *make_unireg_sortorder(ORDER *order, uint *length)
 
 
 /*****************************************************************************
-**	Fill join cache with packed records
-**	Records are stored in tab->cache.buffer and last record in
-**	last record is stored with pointers to blobs to support very big
-**	records
+  Fill join cache with packed records
+  Records are stored in tab->cache.buffer and last record in
+  last record is stored with pointers to blobs to support very big
+  records
 ******************************************************************************/
 
 static int
@@ -5701,7 +5701,7 @@ join_init_cache(THD *thd,JOIN_TAB *tables,uint table_count)
     if (null_fields && tables[i].table->null_fields)
     {						/* must copy null bits */
       copy->str=(char*) tables[i].table->null_flags;
-      copy->length=(tables[i].table->null_fields+7)/8;
+      copy->length=tables[i].table->null_bytes;
       copy->strip=0;
       copy->blob_field=0;
       length+=copy->length;