diff --git a/src/lb.cpp b/src/lb.cpp
index 3ad27394..a53cab3b 100644
--- a/src/lb.cpp
+++ b/src/lb.cpp
@@ -107,7 +107,7 @@ int zmq::lb_t::sendpipe (msg_t *msg_, pipe_t **pipe_)
         // Application should handle this as suitable
         if (more) {
             pipes[current]->rollback ();
-            more = 0;
+            more = false;
             errno = EAGAIN;
             return -1;
         }
diff --git a/src/options.cpp b/src/options.cpp
index 1753bb21..fa39fcbd 100644
--- a/src/options.cpp
+++ b/src/options.cpp
@@ -209,7 +209,7 @@ zmq::options_t::options_t () :
     maxmsgsize (-1),
     rcvtimeo (-1),
     sndtimeo (-1),
-    ipv6 (0),
+    ipv6 (false),
     immediate (0),
     filter (false),
     invert_matching (false),
diff --git a/src/session_base.cpp b/src/session_base.cpp
index 4b25b251..ecf3aa2c 100644
--- a/src/session_base.cpp
+++ b/src/session_base.cpp
@@ -441,9 +441,9 @@ void zmq::session_base_t::engine_error (
         case stream_engine_t::protocol_error:
             if (pending) {
                 if (pipe)
-                    pipe->terminate (0);
+                    pipe->terminate (false);
                 if (zap_pipe)
-                    zap_pipe->terminate (0);
+                    zap_pipe->terminate (false);
             } else {
                 terminate ();
             }
diff --git a/src/xpub.cpp b/src/xpub.cpp
index cfb62a84..a7fcda89 100644
--- a/src/xpub.cpp
+++ b/src/xpub.cpp
@@ -162,7 +162,7 @@ int zmq::xpub_t::xsetsockopt (int option_,
         }
         if (option_ == ZMQ_XPUB_VERBOSE) {
             verbose_subs = (*static_cast<const int *> (optval_) != 0);
-            verbose_unsubs = 0;
+            verbose_unsubs = false;
         } else if (option_ == ZMQ_XPUB_VERBOSER) {
             verbose_subs = (*static_cast<const int *> (optval_) != 0);
             verbose_unsubs = verbose_subs;