diff --git a/folly/io/async/AsyncSSLSocket.cpp b/folly/io/async/AsyncSSLSocket.cpp
index 564438c60cfb551953d4064af4c7a24ff9cd5f27..b0e54e67fd62e6ce1aa4b05bee1f9ee5715a2faa 100644
--- a/folly/io/async/AsyncSSLSocket.cpp
+++ b/folly/io/async/AsyncSSLSocket.cpp
@@ -824,6 +824,7 @@ bool AsyncSSLSocket::getSelectedNextProtocolNoThrow(
   }
   return true;
 #else
+  (void)protoType;
   return false;
 #endif
 }