diff --git a/qrexec/qrexec-client.c b/qrexec/qrexec-client.c
index 47a58c5..8ceeffd 100644
--- a/qrexec/qrexec-client.c
+++ b/qrexec/qrexec-client.c
@@ -155,7 +155,7 @@ static int connect_unix_socket(const char *domname)
     return s;
 }
 
-static void sigchld_handler(int x)
+static void sigchld_handler(int x __attribute__((__unused__)))
 {
     child_exited = 1;
     signal(SIGCHLD, sigchld_handler);
@@ -192,7 +192,7 @@ static void prepare_local_fds(char *cmdline)
 }
 
 /* ask the daemon to allocate vchan port */
-static void negotiate_connection_params(int s, int other_domid, int type,
+static void negotiate_connection_params(int s, int other_domid, unsigned type,
         void *cmdline_param, int cmdline_size,
         int *data_domain, int *data_port)
 {
@@ -255,11 +255,11 @@ static void send_exit_code(libvchan_t *vchan, int status)
 
     hdr.type = MSG_DATA_EXIT_CODE;
     hdr.len = sizeof(int);
-    if (libvchan_send(vchan, &hdr, sizeof(hdr)) < sizeof(hdr)) {
+    if (libvchan_send(vchan, &hdr, sizeof(hdr)) != sizeof(hdr)) {
         fprintf(stderr, "Failed to write exit code to the agent\n");
         do_exit(1);
     }
-    if (libvchan_send(vchan, &status, sizeof(status)) < sizeof(status)) {
+    if (libvchan_send(vchan, &status, sizeof(status)) != sizeof(status)) {
         fprintf(stderr, "Failed to write exit code(2) to the agent\n");
         do_exit(1);
     }
@@ -278,7 +278,7 @@ static void handle_input(libvchan_t *vchan)
     }
     hdr.type = is_service ? MSG_DATA_STDOUT : MSG_DATA_STDIN;
     hdr.len = ret;
-    if (libvchan_send(vchan, &hdr, sizeof(hdr)) < sizeof(hdr)) {
+    if (libvchan_send(vchan, &hdr, sizeof(hdr)) != sizeof(hdr)) {
         fprintf(stderr, "Failed to write STDIN data to the agent\n");
         do_exit(1);
     }
diff --git a/qrexec/qrexec-daemon.c b/qrexec/qrexec-daemon.c
index 3c91b5e..291e2e5 100644
--- a/qrexec/qrexec-daemon.c
+++ b/qrexec/qrexec-daemon.c
@@ -181,7 +181,7 @@ int handle_agent_hello(libvchan_t *ctrl, const char *domain_name)
     struct msg_header hdr;
     struct peer_info info;
 
-    if (libvchan_recv(ctrl, &hdr, sizeof(hdr)) < sizeof(hdr)) {
+    if (libvchan_recv(ctrl, &hdr, sizeof(hdr)) != sizeof(hdr)) {
         fprintf(stderr, "Failed to read agent HELLO hdr\n");
         return -1;
     }
@@ -191,7 +191,7 @@ int handle_agent_hello(libvchan_t *ctrl, const char *domain_name)
         return -1;
     }
 
-    if (libvchan_recv(ctrl, &info, sizeof(info)) < sizeof(info)) {
+    if (libvchan_recv(ctrl, &info, sizeof(info)) != sizeof(info)) {
         fprintf(stderr, "Failed to read agent HELLO body\n");
         return -1;
     }
@@ -209,12 +209,12 @@ int handle_agent_hello(libvchan_t *ctrl, const char *domain_name)
     hdr.len = sizeof(info);
     info.version = QREXEC_PROTOCOL_VERSION;
 
-    if (libvchan_send(ctrl, &hdr, sizeof(hdr)) < sizeof(hdr)) {
+    if (libvchan_send(ctrl, &hdr, sizeof(hdr)) != sizeof(hdr)) {
         fprintf(stderr, "Failed to send HELLO hdr to agent\n");
         return -1;
     }
 
-    if (libvchan_send(ctrl, &info, sizeof(info)) < sizeof(info)) {
+    if (libvchan_send(ctrl, &info, sizeof(info)) != sizeof(info)) {
         fprintf(stderr, "Failed to send HELLO hdr to agent\n");
         return -1;
     }
@@ -554,12 +554,12 @@ static void send_service_refused(libvchan_t *vchan, struct service_params *param
     hdr.type = MSG_SERVICE_REFUSED;
     hdr.len = sizeof(*params);
 
-    if (libvchan_send(vchan, &hdr, sizeof(hdr)) < sizeof(hdr)) {
+    if (libvchan_send(vchan, &hdr, sizeof(hdr)) != sizeof(hdr)) {
         fprintf(stderr, "Failed to send MSG_SERVICE_REFUSED hdr to agent\n");
         exit(1);
     }
 
-    if (libvchan_send(vchan, params, sizeof(*params)) < sizeof(*params)) {
+    if (libvchan_send(vchan, params, sizeof(*params)) != sizeof(*params)) {
         fprintf(stderr, "Failed to send MSG_SERVICE_REFUSED to agent\n");
         exit(1);
     }
@@ -809,7 +809,7 @@ int main(int argc, char **argv)
      */
     for (;;) {
         max = fill_fdsets_for_select(&read_fdset, &write_fdset);
-        if (libvchan_buffer_space(vchan) <= sizeof(struct msg_header))
+        if (libvchan_buffer_space(vchan) <= (int)sizeof(struct msg_header))
             FD_ZERO(&read_fdset);	// vchan full - don't read from clients
 
         sigprocmask(SIG_BLOCK, &chld_set, NULL);