diff --git a/src/misc.c b/src/misc.c
index a9f423a6..0e0525e8 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -94,8 +94,10 @@ static int wsa2errno(void)
  * Replacement for the standard recv, return -errno on failure.
  */
 ssize_t
-_libssh2_recv(libssh2_socket_t sock, void *buffer, size_t length, int flags, void **abstract)
+_libssh2_recv(libssh2_socket_t sock, void *buffer, size_t length,
+              int flags, void **abstract)
 {
+    (void) abstract;
     ssize_t rc = recv(sock, buffer, length, flags);
 #ifdef WIN32
     if (rc < 0 )
@@ -128,6 +130,7 @@ ssize_t
 _libssh2_send(libssh2_socket_t sock, const void *buffer, size_t length,
               int flags, void **abstract)
 {
+    (void) abstract;
     ssize_t rc = send(sock, buffer, length, flags);
 #ifdef WIN32
     if (rc < 0 )