From 551de0346fe157f0910b99a2c99e8285d96d1b1c Mon Sep 17 00:00:00 2001
From: beorn7 <beorn@grafana.com>
Date: Wed, 5 Apr 2023 14:31:05 +0200
Subject: [PATCH] promql: Do not return nil slices to the pool

Signed-off-by: beorn7 <beorn@grafana.com>
---
 promql/engine.go | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/promql/engine.go b/promql/engine.go
index 4c6751088f..b49be244f1 100644
--- a/promql/engine.go
+++ b/promql/engine.go
@@ -1874,7 +1874,9 @@ func getFPointSlice(sz int) []FPoint {
 }
 
 func putFPointSlice(p []FPoint) {
-	fPointPool.Put(p[:0])
+	if p != nil {
+		fPointPool.Put(p[:0])
+	}
 }
 
 func getHPointSlice(sz int) []HPoint {
@@ -1885,7 +1887,9 @@ func getHPointSlice(sz int) []HPoint {
 }
 
 func putHPointSlice(p []HPoint) {
-	hPointPool.Put(p[:0])
+	if p != nil {
+		hPointPool.Put(p[:0])
+	}
 }
 
 // matrixSelector evaluates a *parser.MatrixSelector expression.