From 7a5df2126081b83d29758ef31f9f38369ac85ae4 Mon Sep 17 00:00:00 2001
From: Paolo Barbolini <paolo.barbolini@m4ss.net>
Date: Wed, 20 Mar 2024 22:02:00 +0100
Subject: [PATCH] fix: could panic if http2 disabled but TLS negotiated h2
 (#2194)

The fix is only ask for h2 ALPN iff the http2 feature is enabled.

Closes #2192
---
 src/async_impl/client.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/async_impl/client.rs b/src/async_impl/client.rs
index 926e21e59..a64869582 100644
--- a/src/async_impl/client.rs
+++ b/src/async_impl/client.rs
@@ -590,7 +590,11 @@ impl ClientBuilder {
                             tls.alpn_protocols = vec!["h3".into()];
                         }
                         HttpVersionPref::All => {
-                            tls.alpn_protocols = vec!["h2".into(), "http/1.1".into()];
+                            tls.alpn_protocols = vec![
+                                #[cfg(feature = "http2")]
+                                "h2".into(),
+                                "http/1.1".into(),
+                            ];
                         }
                     }