many fixes

libmysql/libmysql.c:
  Fixes a very rare bug when variable name (without '_') and it's 
  value are at the very end of the config file.
  
  I have tested it , but would liek little mobster to test it further
mysql-test/r/union.result:
  results for union test that proves that EXPLAIN UNION bugs are fixed
mysql-test/t/union.test:
  additional tests for EXPLAIN on UNION's that have previously failed
sql/sql_yacc.yy:
  Some small fixes for newer parsers.
  Only unsigned int yystacksize remains to be fixed.
  This I leave to Monty.
  Present fixes are only aesthetic and do not harm.

1 files changed, 15 insertions, 0 deletions

diff --git a/mysql-test/r/union.result b/mysql-test/r/union.result
index 6a27df648b5..e842bb3b447 100644
--- a/mysql-test/r/union.result
+++ b/mysql-test/r/union.result
@@ -86,6 +86,21 @@ explain select a,b from t1 union all select a,b from t2;
 table	type	possible_keys	key	key_len	ref	rows	Extra
 t1	ALL	NULL	NULL	NULL	NULL	4	
 t2	ALL	NULL	NULL	NULL	NULL	4	
+explain select xx from t1 union select 1;
+Unknown column 'xx' in 'field list'
+explain select a,b from t1 union select 1;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	ALL	NULL	NULL	NULL	NULL	4	
+				0		0	No tables used
+explain select 1 union select a,b from t1 union select 1;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+				0		0	No tables used
+t1	ALL	NULL	NULL	NULL	NULL	4	
+				0		0	No tables used
+explain select a,b from t1 union select 1 limit 0;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	ALL	NULL	NULL	NULL	NULL	4	
+				0		0	Impossible WHERE
 select a,b from t1 into outfile 'skr' union select a,b from t2;
 Wrong usage of UNION and INTO
 select a,b from t1 order by a union select a,b from t2;