Fixed BUG#8409: Stored procedure crash if function contains FLUSH

  by simply disabling FLUSH for stored functions. (I can't really work.)

mysql-test/r/sp-error.result

@@ -646,4 +646,12 @@ drop procedure if exists bug10537|
 create procedure bug10537()
 load data local infile '/tmp/somefile' into table t1|
 ERROR 0A000: LOAD DATA is not allowed in stored procedures
+drop function if exists bug8409|
+create function bug8409()
+returns int
+begin
+flush tables;
+return 5;
+end|
+ERROR 0A000: FLUSH is not allowed in stored procedures
 drop table t1|

mysql-test/t/sp-error.test

@@ -905,6 +905,21 @@ create procedure bug10537()
   load data local infile '/tmp/somefile' into table t1|
 
 
+#
+# BUG#8409: Stored procedure crash if function contains FLUSH
+#
+--disable_warnings
+drop function if exists bug8409|
+--enable_warnings
+--error ER_SP_BADSTATEMENT
+create function bug8409()
+  returns int
+begin
+  flush tables;
+  return 5;
+end|
+
+
 #
 # BUG#NNNN: New bug synopsis
 #

sql/sql_yacc.yy

@@ -6511,6 +6511,11 @@ flush:
 	FLUSH_SYM opt_no_write_to_binlog
 	{
 	  LEX *lex=Lex;
+	  if (lex->sphead && lex->sphead->m_type == TYPE_ENUM_FUNCTION)
+	  {
+	    my_error(ER_SP_BADSTATEMENT, MYF(0), "FLUSH");
+	    YYABORT;
+	  }
 	  lex->sql_command= SQLCOM_FLUSH; lex->type=0;
           lex->no_write_to_binlog= $2;
 	}