Problem: return code of make_fdpair() is not checked. Fixes #1558

src/signaler.cpp

@@ -124,10 +124,11 @@ static int close_wait_ms (int fd_, unsigned int max_ms_ = 2000)
 zmq::signaler_t::signaler_t ()
 {
     //  Create the socketpair for signaling.
-    if (make_fdpair (&r, &w) == 0) {
-        unblock_socket (w);
-        unblock_socket (r);
-    }
+    int rc = make_fdpair (&r, &w);
+    zmq_assert (rc == 0);
+
+    unblock_socket (w);
+    unblock_socket (r);
 #ifdef HAVE_FORK
     pid = getpid ();
 #endif
@@ -321,7 +322,8 @@ void zmq::signaler_t::forked ()
     //  Close file descriptors created in the parent and create new pair
     close (r);
     close (w);
-    make_fdpair (&r, &w);
+    int rc = make_fdpair (&r, &w);
+    zmq_assert (rc == 0);
 }
 #endif