diff --git a/CHANGELOG.md b/CHANGELOG.md
index 114eef55d7..e929f49a31 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 ### Added
 
 - [#7907](https://github.com/thanos-io/thanos/pull/7907) Receive: Add `--receive.grpc-service-config` flag to configure gRPC service config for the receivers.
+- [#7957](https://github.com/thanos-io/thanos/pull/7957) Compact, Store Gateway: Compactor will set series p90, p99, p999 and p9999 size in `meta.json` file. Lazy expanded postings will choose estimated series size based on `estimated-series-size-stat` flag.
 
 ### Changed
 
diff --git a/pkg/block/index.go b/pkg/block/index.go
index 217d9b7e0e..091c93c53a 100644
--- a/pkg/block/index.go
+++ b/pkg/block/index.go
@@ -229,7 +229,8 @@ func newSketch() *sketch {
 
 func (s *sketch) Add(v int64) {
 	s.cnt++
-	s.s.Add(float64(v))
+	// Impossible to happen since v should > 0.
+	_ = s.s.Add(float64(v))
 }
 
 func (s *sketch) Avg() int64 {