Correct broken unaligned load/store in armv5 (#1355)

Update vendor github.com/boltdb/bolt to take care of the issue #1354.

vendor/github.com/boltdb/bolt/tx.go

@@ -381,7 +381,9 @@ func (tx *Tx) Check() <-chan error {
 func (tx *Tx) check(ch chan error) {
 	// Check if any pages are double freed.
 	freed := make(map[pgid]bool)
-	for _, id := range tx.db.freelist.all() {
+	all := make([]pgid, tx.db.freelist.count())
+	tx.db.freelist.copyall(all)
+	for _, id := range all {
 		if freed[id] {
 			ch <- fmt.Errorf("page %d: already freed", id)
 		}
@@ -473,6 +475,8 @@ func (tx *Tx) write() error {
 	for _, p := range tx.pages {
 		pages = append(pages, p)
 	}
+	// Clear out page cache early.
+	tx.pages = make(map[pgid]*page)
 	sort.Sort(pages)
 
 	// Write pages to disk in order.
@@ -517,8 +521,22 @@ func (tx *Tx) write() error {
 		}
 	}
 
-	// Clear out page cache.
-	tx.pages = make(map[pgid]*page)
+	// Put small pages back to page pool.
+	for _, p := range pages {
+		// Ignore page sizes over 1 page.
+		// These are allocated using make() instead of the page pool.
+		if int(p.overflow) != 0 {
+			continue
+		}
+
+		buf := (*[maxAllocSize]byte)(unsafe.Pointer(p))[:tx.db.pageSize]
+
+		// See https://go.googlesource.com/go/+/f03c9202c43e0abb130669852082117ca50aa9b1
+		for i := range buf {
+			buf[i] = 0
+		}
+		tx.db.pagePool.Put(buf)
+	}
 
 	return nil
 }