Fixed bug #643, which caused intermittent crashes in net_printf() with repeated

syntax errors in stored procedures.

mysql-test/r/sp-error.result

 delete from mysql.proc;
+create procedure syntaxerror(t int);
+You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
+create procedure syntaxerror(t int);
+You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
+create procedure syntaxerror(t int);
+You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
 create procedure proc1()
 set @x = 42;
 create function func1() returns int

mysql-test/t/sp-error.test

@@ -7,6 +7,16 @@ delete from mysql.proc;
 
 delimiter |;
 
+# This should give three syntax errors (sometimes crashed; bug #643)
+# (Unfortunately, this is not a 100% test, on some platforms this
+#  passed despite the bug.)
+--error 1064
+create procedure syntaxerror(t int)|
+--error 1064
+create procedure syntaxerror(t int)|
+--error 1064
+create procedure syntaxerror(t int)|
+
 # Check that we get the right error, i.e. UDF declaration parses correctly,
 # but foo.so doesn't exist.
 # QQ This generates an error message containing a misleading errno which

sql/sp_head.cc

@@ -376,6 +376,7 @@ sp_head::reset_lex(THD *thd)
   /* We must reset ptr and end_of_query again */
   sublex->ptr= m_lex->ptr;
   sublex->end_of_query= m_lex->end_of_query;
+  sublex->tok_start= m_lex->tok_start;
   /* And keep the SP stuff too */
   sublex->sphead= m_lex->sphead;
   sublex->spcont= m_lex->spcont;