diff --git a/src/devpoll.cpp b/src/devpoll.cpp
index 0c46d14b..97c1ec04 100644
--- a/src/devpoll.cpp
+++ b/src/devpoll.cpp
@@ -70,7 +70,7 @@ zmq::devpoll_t::handle_t zmq::devpoll_t::add_fd (fd_t fd_,
         }
     }
 
-    assert (!fd_table [fd_].valid);
+    zmq_assert (!fd_table [fd_].valid);
 
     fd_table [fd_].events = 0;
     fd_table [fd_].reactor = reactor_;
@@ -88,7 +88,7 @@ zmq::devpoll_t::handle_t zmq::devpoll_t::add_fd (fd_t fd_,
 
 void zmq::devpoll_t::rm_fd (handle_t handle_)
 {
-    assert (fd_table [handle_].valid);
+    zmq_assert (fd_table [handle_].valid);
 
     devpoll_ctl (handle_, POLLREMOVE);
     fd_table [handle_].valid = false;
diff --git a/src/poll.cpp b/src/poll.cpp
index 1d1c4233..de7e0da3 100644
--- a/src/poll.cpp
+++ b/src/poll.cpp
@@ -57,7 +57,7 @@ zmq::poll_t::handle_t zmq::poll_t::add_fd (fd_t fd_, i_poll_events *events_)
 
     pollfd pfd = {fd_, 0, 0};
     pollset.push_back (pfd);
-    assert (fd_table [fd_].index == retired_fd);
+    zmq_assert (fd_table [fd_].index == retired_fd);
 
     fd_table [fd_].index = pollset.size() - 1;
     fd_table [fd_].events = events_;
@@ -71,7 +71,7 @@ zmq::poll_t::handle_t zmq::poll_t::add_fd (fd_t fd_, i_poll_events *events_)
 void zmq::poll_t::rm_fd (handle_t handle_)
 {
     fd_t index = fd_table [handle_].index;
-    assert (index != retired_fd);
+    zmq_assert (index != retired_fd);
 
     //  Mark the fd as unused.
     pollset [index].fd = retired_fd;
diff --git a/src/router.cpp b/src/router.cpp
index c8877280..3a45de6f 100644
--- a/src/router.cpp
+++ b/src/router.cpp
@@ -219,8 +219,8 @@ int zmq::router_t::xrecv (msg_t *msg_, int flags_)
     }
 
     //  Identity is not expected
-    assert ((msg_->flags () & msg_t::identity) == 0);
-    assert (pipe != NULL);
+    zmq_assert ((msg_->flags () & msg_t::identity) == 0);
+    zmq_assert (pipe != NULL);
 
     //  If we are in the middle of reading a message, just return the next part.
     if (more_in)
@@ -273,7 +273,7 @@ bool zmq::router_t::xhas_in ()
         return false;
 
     //  Identity is not expected
-    assert ((prefetched_msg.flags () & msg_t::identity) == 0);
+    zmq_assert ((prefetched_msg.flags () & msg_t::identity) == 0);
 
     blob_t identity = pipe->get_identity ();
     rc = prefetched_id.init_size (identity.size ());