Fixed BUG#8638: Test 'sp' fails: Stored Procedure often sends warning 1329

  The warning sent is by itself ok, the problem was rather why it wasn't
  sent on some other platforms...
  The real problem was that a total_warn_count which was inconsistent with warn_list
  was sent back with send_eof() during SP execution, which in turn cause a protocol
  error in mysqltest.

mysql-test/r/sp.result

@@ -656,7 +656,6 @@ delete from t1|
 drop table if exists t3|
 create table t3 ( s char(16), d int)|
 call into_test4()|
-Warnings:
 select * from t3|
 s	d
 into4	NULL
@@ -1344,9 +1343,7 @@ end if;
 insert into t4 values (2, rc, t3);
 end|
 call bug1863(10)|
-Warnings:
 call bug1863(10)|
-Warnings:
 select * from t4|
 f1	rc	t3
 2	0	NULL
@@ -1643,9 +1640,7 @@ begin
 end|
 call bug4579_1()|
 call bug4579_1()|
-Warnings:
 call bug4579_1()|
-Warnings:
 drop procedure bug4579_1|
 drop procedure bug4579_2|
 drop table t3|
@@ -2118,12 +2113,16 @@ var
 call bug7743("OneWord")|
 var
 NULL
+Warnings:
+Warning	1329	No data to FETCH
 call bug7743("anotherword")|
 var
 2
 call bug7743("AnotherWord")|
 var
 NULL
+Warnings:
+Warning	1329	No data to FETCH
 drop procedure bug7743|
 drop table t4|
 delete from t3|

sql/protocol.cc

@@ -359,7 +359,9 @@ send_eof(THD *thd, bool no_flush)
     if (thd->client_capabilities & CLIENT_PROTOCOL_41)
     {
       uchar buff[5];
-      uint tmp= min(thd->total_warn_count, 65535);
+      /* Don't send warn count during SP execution, as the warn_list
+         is cleared between substatements, and mysqltest gets confused */
+      uint tmp= (thd->spcont ? 0 : min(thd->total_warn_count, 65535));
       buff[0]=254;
       int2store(buff+1, tmp);
       /*

sql/sql_parse.cc

@@ -4185,6 +4185,12 @@ mysql_execute_command(THD *thd)
 	thd->row_count_func= 0;
 	res= sp->execute_procedure(thd, &lex->value_list);
 
+	/* If warnings have been cleared, we have to clear total_warn_count
+	 * too, otherwise the clients get confused.
+	 */
+	if (thd->warn_list.is_empty())
+	  thd->total_warn_count= 0;
+
 	thd->variables.select_limit= select_limit;
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
 	sp_restore_security_context(thd, sp, &save_ctx);