diff --git a/src/tcp/ack.ml b/src/tcp/ack.ml
index d12b99dd..0385ed2e 100644
--- a/src/tcp/ack.ml
+++ b/src/tcp/ack.ml
@@ -37,7 +37,7 @@ end
 module Immediate : M = struct
 
   type t = {
-    mutable send_ack: Sequence.t Lwt_mvar.t;
+    send_ack: Sequence.t Lwt_mvar.t;
     mutable pushpending: bool;
   }
 
diff --git a/src/tcp/segment.ml b/src/tcp/segment.ml
index 75872594..c27e9367 100644
--- a/src/tcp/segment.ml
+++ b/src/tcp/segment.ml
@@ -14,8 +14,6 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
-[@@@ocaml.warning "-3"]
-
 open Lwt.Infix
 
 let src = Logs.Src.create "tcp.segment" ~doc:"Mirage TCP Segment module"
diff --git a/src/tcp/user_buffer.ml b/src/tcp/user_buffer.ml
index 0b1f5325..4ef00221 100644
--- a/src/tcp/user_buffer.ml
+++ b/src/tcp/user_buffer.ml
@@ -15,8 +15,6 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
-[@@@ocaml.warning "-3"]
-
 open Lwt.Infix
 
 let lwt_sequence_add_l s seq =