From 77b93d41d55d4bc359f631908d1a86bf8e8532c8 Mon Sep 17 00:00:00 2001
From: Alexander Yastrebov <yastrebov.alex@gmail.com>
Date: Sat, 6 Sep 2025 12:24:20 +0000
Subject: [PATCH] net/http: add comments for transport gzip reader

Add back comments dropped in CL 510255

Updates #61353

Change-Id: Ie84610b830599e178140bb5c2a11be74b2ad461e
GitHub-Last-Rev: d6cd890dd15aa0f2f8701cf66da11a844bbd011d
GitHub-Pull-Request: golang/go#75293
Reviewed-on: https://go-review.googlesource.com/c/go/+/701395
Reviewed-by: Sean Liao <sean@liao.dev>
Reviewed-by: Mark Freeman <markfreeman@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
---
 src/net/http/transport.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/net/http/transport.go b/src/net/http/transport.go
index c5b1a87c5c..139ad84af0 100644
--- a/src/net/http/transport.go
+++ b/src/net/http/transport.go
@@ -3046,8 +3046,8 @@ type gzipReader struct {
 	_    incomparable
 	body *bodyEOFSignal // underlying HTTP/1 response body framing
 	mu   sync.Mutex     // guards zr and zerr
-	zr   *gzip.Reader
-	zerr error
+	zr   *gzip.Reader   // stores gzip reader from the pool between reads
+	zerr error          // sticky gzip reader init error or sentinel value to detect concurrent read and read after close
 }
 
 type eofReader struct{}
-- 
2.52.0