diff --git a/src/gssapi_mechanism_base.cpp b/src/gssapi_mechanism_base.cpp
index b4346914..f00591bd 100644
--- a/src/gssapi_mechanism_base.cpp
+++ b/src/gssapi_mechanism_base.cpp
@@ -80,6 +80,8 @@ int zmq::gssapi_mechanism_base_t::encode_message (msg_t *msg_)
         flags |= 0x02;
 
     uint8_t *plaintext_buffer = static_cast <uint8_t *>(malloc(msg_->size ()+1));
+    alloc_assert(plaintext_buffer);
+
     plaintext_buffer[0] = flags;
     memcpy (plaintext_buffer+1, msg_->data(), msg_->size());
 
diff --git a/src/norm_engine.cpp b/src/norm_engine.cpp
index 6f813346..56bd835d 100644
--- a/src/norm_engine.cpp
+++ b/src/norm_engine.cpp
@@ -416,6 +416,7 @@ void zmq::norm_engine_t::recv_data(NormObjectHandle object)
         {
             // This is a new stream, so create rxState with zmq decoder, etc
             rxState = new (std::nothrow) NormRxStreamState(object, options.maxmsgsize);
+            errno_assert(rxState);
 
             if (!rxState->Init())
             {
diff --git a/src/req.cpp b/src/req.cpp
index 233354ac..4871df6e 100644
--- a/src/req.cpp
+++ b/src/req.cpp
@@ -84,6 +84,8 @@ int zmq::req_t::xsend (msg_t *msg_)
 
             //  Copy request id before sending (see issue #1695 for details).
             uint32_t *request_id_copy = (uint32_t *) malloc (sizeof (uint32_t));
+            zmq_assert (request_id_copy);
+
             *request_id_copy = request_id;
 
             msg_t id;
diff --git a/src/signaler.cpp b/src/signaler.cpp
index ff42c110..6f69313e 100644
--- a/src/signaler.cpp
+++ b/src/signaler.cpp
@@ -533,6 +533,8 @@ int zmq::signaler_t::make_fdpair (fd_t *r_, fd_t *w_)
     if (*r_ != INVALID_SOCKET) {
         size_t dummy_size = 1024 * 1024;        //  1M to overload default receive buffer
         unsigned char *dummy = (unsigned char *) malloc (dummy_size);
+        wsa_assert (dummy);
+
         int still_to_send = (int) dummy_size;
         int still_to_recv = (int) dummy_size;
         while (still_to_send || still_to_recv) {
diff --git a/src/socket_base.cpp b/src/socket_base.cpp
index f7b5440f..2eec07ce 100644
--- a/src/socket_base.cpp
+++ b/src/socket_base.cpp
@@ -204,9 +204,13 @@ zmq::socket_base_t::socket_base_t (ctx_t *parent_, uint32_t tid_, int sid_, bool
     options.linger = parent_->get (ZMQ_BLOCKY)? -1: 0;
 
     if (thread_safe)
+    {
         mailbox = new (std::nothrow) mailbox_safe_t(&sync);
+        zmq_assert (mailbox);
+    }
     else {
         mailbox_t *m = new (std::nothrow) mailbox_t();
+        zmq_assert (m);
 
         if (m->get_fd () != retired_fd)
             mailbox = m;
@@ -1300,6 +1304,7 @@ void zmq::socket_base_t::start_reaping (poller_t *poller_)
         scoped_optional_lock_t sync_lock(thread_safe ? &sync : NULL);
 
         reaper_signaler = new (std::nothrow) signaler_t();
+        zmq_assert (reaper_signaler);
 
         //  Add signaler to the safe mailbox
         fd = reaper_signaler->get_fd();
diff --git a/src/stream_engine.cpp b/src/stream_engine.cpp
index 4eacdc90..1f38983a 100644
--- a/src/stream_engine.cpp
+++ b/src/stream_engine.cpp
@@ -212,6 +212,7 @@ void zmq::stream_engine_t::plug (io_thread_t *io_thread_,
             //  Compile metadata.
             zmq_assert (metadata == NULL);
             metadata = new (std::nothrow) metadata_t (properties);
+            alloc_assert (metadata);
         }
 
         if (options.raw_notify) {
@@ -861,7 +862,10 @@ void zmq::stream_engine_t::mechanism_ready ()
 
     zmq_assert (metadata == NULL);
     if (!properties.empty ())
+    {
         metadata = new (std::nothrow) metadata_t (properties);
+        alloc_assert (metadata);
+    }
 
 #ifdef ZMQ_BUILD_DRAFT_API
     socket->event_handshake_succeed(endpoint, 0);
diff --git a/src/zmq_utils.cpp b/src/zmq_utils.cpp
index 88b90344..47b09e37 100644
--- a/src/zmq_utils.cpp
+++ b/src/zmq_utils.cpp
@@ -77,6 +77,7 @@ unsigned long zmq_stopwatch_stop (void *watch_)
 void *zmq_threadstart(zmq_thread_fn* func, void* arg)
 {
     zmq::thread_t* thread = new (std::nothrow) zmq::thread_t;
+    alloc_assert(thread);
     thread->start(func, arg);
     return thread;
 }