diff --git a/src/mechanism.cpp b/src/mechanism.cpp
index d5e84a18..fd34bc0f 100644
--- a/src/mechanism.cpp
+++ b/src/mechanism.cpp
@@ -133,8 +133,8 @@ int zmq::mechanism_t::parse_metadata (const unsigned char *ptr_,
     return 0;
 }
 
-int zmq::mechanism_t::property (const std::string name_,
-                                const void *value_, size_t length_)
+int zmq::mechanism_t::property (const std::string /* name_ */,
+                                const void * /* value_ */, size_t /* length_ */)
 {
     //  Default implementation does not check
     //  property values and returns 0 to signal success.
diff --git a/src/mechanism.hpp b/src/mechanism.hpp
index f2a45d3a..2e40d8fd 100644
--- a/src/mechanism.hpp
+++ b/src/mechanism.hpp
@@ -46,9 +46,9 @@ namespace zmq
         //  Process the handshake command received from the peer.
         virtual int process_handshake_command (msg_t *msg_) = 0;
 
-        virtual int encode (msg_t *msg_) { return 0; }
+        virtual int encode (msg_t *) { return 0; }
 
-        virtual int decode (msg_t *msg_) { return 0; }
+        virtual int decode (msg_t *) { return 0; }
 
         //  Notifies mechanism about availability of ZAP message.
         virtual int zap_msg_available () { return 0; }
diff --git a/src/stream.cpp b/src/stream.cpp
index c7d35597..fc4d3800 100644
--- a/src/stream.cpp
+++ b/src/stream.cpp
@@ -166,9 +166,6 @@ int zmq::stream_t::xsend (msg_t *msg_)
 int zmq::stream_t::xsetsockopt (int option_, const void *optval_,
     size_t optvallen_)
 {
-    bool is_int = (optvallen_ == sizeof (int));
-    int value = is_int? *((int *) optval_): 0;
-
     switch (option_) {
         case ZMQ_NEXT_IDENTITY:
             if(optval_ && optvallen_) {
@@ -268,7 +265,7 @@ void zmq::stream_t::identify_peer (pipe_t *pipe_)
             next_identity.length());
         next_identity.clear();
     }
-    else { 
+    else {
         put_uint32 (buffer + 1, next_peer_id++);
         blob_t identity = blob_t (buffer, sizeof buffer);
         memcpy (options.identity, identity.data (), identity.size ());
diff --git a/src/stream_engine.cpp b/src/stream_engine.cpp
index 63485049..5e9e2965 100644
--- a/src/stream_engine.cpp
+++ b/src/stream_engine.cpp
@@ -182,7 +182,7 @@ void zmq::stream_engine_t::plug (io_thread_t *io_thread_,
         // application so that it knows a peer has connected.
         msg_t connector;
         connector.init();
-        int rc = (this->*write_msg) (&connector);
+        (this->*write_msg) (&connector);
         connector.close();
         session->flush ();
     }
diff --git a/src/ypipe_conflate.hpp b/src/ypipe_conflate.hpp
index 31d0f3d5..94698acf 100644
--- a/src/ypipe_conflate.hpp
+++ b/src/ypipe_conflate.hpp
@@ -70,7 +70,7 @@ namespace zmq
 #endif
 
         // There are no incomplete items for conflate ypipe
-        inline bool unwrite (T *value_)
+        inline bool unwrite (T *)
         {
             return false;
         }
diff --git a/src/zmq_utils.cpp b/src/zmq_utils.cpp
index d6b3b650..d132db03 100644
--- a/src/zmq_utils.cpp
+++ b/src/zmq_utils.cpp
@@ -188,12 +188,13 @@ int zmq_curve_keypair (char *z85_public_key, char *z85_secret_key)
     //  Is there a sensible errno to set here?
     if (rc)
         return rc;
-    
+
     zmq_z85_encode (z85_public_key, public_key, 32);
     zmq_z85_encode (z85_secret_key, secret_key, 32);
-    
+
     return 0;
 #else // requires libsodium
+    (void) z85_public_key, (void) z85_secret_key;
     errno = ENOTSUP;
     return -1;
 #endif
diff --git a/tests/test_conflate.cpp b/tests/test_conflate.cpp
index 647ad0f3..63480e3d 100644
--- a/tests/test_conflate.cpp
+++ b/tests/test_conflate.cpp
@@ -19,7 +19,7 @@
 
 #include "testutil.hpp"
 
-int main (int argc, char *argv [])
+int main (int, char *[])
 {
     const char *bind_to = "tcp://127.0.0.1:5555";
 
diff --git a/tests/test_disconnect_inproc.cpp b/tests/test_disconnect_inproc.cpp
index b6381d34..475ce0b0 100644
--- a/tests/test_disconnect_inproc.cpp
+++ b/tests/test_disconnect_inproc.cpp
@@ -28,7 +28,7 @@ memcpy(zmq_msg_data(&msg), data, size + 1);
 int publicationsReceived = 0;
 bool isSubscribed = false;
 
-int main(int argc, char** argv) {
+int main(int, char**) {
     setup_test_environment();
     void* context = zmq_ctx_new();
     void* pubSocket;
diff --git a/tests/test_hwm.cpp b/tests/test_hwm.cpp
index f7bbf170..4903248c 100644
--- a/tests/test_hwm.cpp
+++ b/tests/test_hwm.cpp
@@ -202,7 +202,7 @@ int test_inproc_connect_and_close_first (int send_hwm, int recv_hwm)
     return send_count;
 }
 
-int test_inproc_bind_and_close_first (int send_hwm, int recv_hwm)
+int test_inproc_bind_and_close_first (int send_hwm, int /* recv_hwm */)
 {
     void *ctx = zmq_ctx_new ();
     assert (ctx);
diff --git a/tests/test_stream.cpp b/tests/test_stream.cpp
index 7b86f6b0..3841087d 100644
--- a/tests/test_stream.cpp
+++ b/tests/test_stream.cpp
@@ -36,10 +36,10 @@ typedef struct {
 //  8-byte size is set to 1 for backwards compatibility
 
 static zmtp_greeting_t greeting
-    = { { 0xFF, 0, 0, 0, 0, 0, 0, 0, 1, 0x7F }, { 3, 0 }, { 'N', 'U', 'L', 'L'} };
+= { { 0xFF, 0, 0, 0, 0, 0, 0, 0, 1, 0x7F }, { 3, 0 }, { 'N', 'U', 'L', 'L'}, 0, { 0 } };
 
 static void
-test_stream_to_dealer (void) 
+test_stream_to_dealer (void)
 {
     int rc;
 
diff --git a/tests/test_stream_disconnect_notifications.cpp b/tests/test_stream_disconnect_notifications.cpp
index a0769ec9..3bf344cf 100644
--- a/tests/test_stream_disconnect_notifications.cpp
+++ b/tests/test_stream_disconnect_notifications.cpp
@@ -52,7 +52,7 @@ bool get_identity (void* socket, char* data, size_t* size)
     return rc == 0;
 }
 
-int main(int argc, char** argv)
+int main(int, char**)
 {
     setup_test_environment();