From 7e5045674c6b44fe5bb1ff04fa0d644bd4e0fbce Mon Sep 17 00:00:00 2001
From: siddontang <siddontang@gmail.com>
Date: Wed, 9 Sep 2015 09:25:11 +0800
Subject: [PATCH 1/3] tidb: try to fix the panic #57

---
 driver.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/driver.go b/driver.go
index b32fc5f81b..55f907579c 100644
--- a/driver.go
+++ b/driver.go
@@ -347,6 +347,7 @@ type driverRows struct {
 	rs   rset.Recordset
 	done chan int
 	rows chan interface{}
+	wg   sync.WaitGroup
 }
 
 func newEmptyDriverRows() *driverRows {
@@ -363,7 +364,9 @@ func newdriverRows(rs rset.Recordset) *driverRows {
 		done: make(chan int),
 		rows: make(chan interface{}, 500),
 	}
+	r.wg.Add(1)
 	go func() {
+		defer r.wg.Done()
 		err := io.EOF
 		if e := r.rs.Do(func(data []interface{}) (bool, error) {
 			vv, cloneErr := types.Clone(data)
@@ -406,6 +409,7 @@ func (r *driverRows) Columns() []string {
 // Close closes the rows iterator.
 func (r *driverRows) Close() error {
 	close(r.done)
+	r.wg.Wait()
 	return nil
 }
 

From 533e26357b7c4eb52beb26cc74eecd1ca9bf59ea Mon Sep 17 00:00:00 2001
From: siddontang <siddontang@gmail.com>
Date: Wed, 9 Sep 2015 12:01:12 +0800
Subject: [PATCH 2/3] tidb: add comment

---
 driver.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/driver.go b/driver.go
index 55f907579c..3afa1fc07e 100644
--- a/driver.go
+++ b/driver.go
@@ -366,6 +366,10 @@ func newdriverRows(rs rset.Recordset) *driverRows {
 	}
 	r.wg.Add(1)
 	go func() {
+		// We may change the whole implementation later, so here just using WaitGroup
+		// to solve issue https://github.com/pingcap/tidb/issues/57
+		// But if we forget close rows and do commit later, we may still meet this panic
+		// with very little probability.
 		defer r.wg.Done()
 		err := io.EOF
 		if e := r.rs.Do(func(data []interface{}) (bool, error) {

From 0cb3800178fee733635613f52eda672bf0834535 Mon Sep 17 00:00:00 2001
From: siddontang <siddontang@gmail.com>
Date: Wed, 9 Sep 2015 12:24:16 +0800
Subject: [PATCH 3/3] Address comment

---
 driver.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/driver.go b/driver.go
index 3afa1fc07e..b41c784a9b 100644
--- a/driver.go
+++ b/driver.go
@@ -366,7 +366,7 @@ func newdriverRows(rs rset.Recordset) *driverRows {
 	}
 	r.wg.Add(1)
 	go func() {
-		// We may change the whole implementation later, so here just using WaitGroup
+		// TODO: We may change the whole implementation later, so here just using WaitGroup
 		// to solve issue https://github.com/pingcap/tidb/issues/57
 		// But if we forget close rows and do commit later, we may still meet this panic
 		// with very little probability.