Index: pyzmq-19.0.0/zmq/utils/mutex.h
--- pyzmq-19.0.0/zmq/utils/mutex.h.orig	2017-11-10 17:11:45.000000000 +0100
+++ pyzmq-19.0.0/zmq/utils/mutex.h	2017-11-10 21:31:04.636120000 +0100
@@ -48,7 +48,7 @@
 
 mutex_t*
 mutex_allocate(void) {
-    mutex_t* mutex = malloc(sizeof(mutex_t));
+    mutex_t* mutex = (mutex_t *)malloc(sizeof(mutex_t));
     _mutex_initialize(mutex);
     return mutex;
 }