diff --git a/sim_frontpanel.c b/sim_frontpanel.c
index 9d9eee17..f15b05e9 100644
--- a/sim_frontpanel.c
+++ b/sim_frontpanel.c
@@ -640,7 +640,7 @@ return 0;
 static int
 _panel_establish_register_bits_collection (PANEL *panel)
 {
-size_t i, buf_data, buf_needed = 1, reg_count = 0, bit_reg_count = 0;
+size_t i, buf_data, buf_needed = 1;
 int cmd_stat, bits_count = 0;
 char *buf, *response = NULL;
 
@@ -753,7 +753,7 @@ struct stat statb;
 char *buf = NULL;
 int port;
 int cmd_stat;
-size_t i, device_num;
+size_t i, device_num = 0;
 char hostport[64];
 union {int i; char c[sizeof (int)]; } end_test;
 
@@ -1444,7 +1444,7 @@ if (!panel->reg_count) {
     }
 pthread_mutex_lock (&panel->io_command_lock);
 pthread_mutex_lock (&panel->io_lock);
-if (panel->reg_query_size != _panel_send (panel, panel->reg_query, panel->reg_query_size)) {
+if ((int)panel->reg_query_size != _panel_send (panel, panel->reg_query, panel->reg_query_size)) {
     pthread_mutex_unlock (&panel->io_lock);
     pthread_mutex_unlock (&panel->io_command_lock);
     return -1;
@@ -2571,7 +2571,6 @@ int sched_policy;
 struct sched_param sched_priority;
 char *buf = NULL;
 size_t buf_data = 0;
-unsigned int callback_count = 0;
 int cmd_stat;
 
 /*
@@ -2594,7 +2593,6 @@ pthread_mutex_lock (&p->io_lock);
 while ((p->sock != INVALID_SOCKET) &&
        (p->usecs_between_callbacks) &&
        (p->State != Error)) {
-    int interval = p->usecs_between_callbacks;
     int new_register = p->new_register;
 
     pthread_mutex_unlock (&p->io_lock);
diff --git a/sim_sock.c b/sim_sock.c
index d03811de..f05a4216 100644
--- a/sim_sock.c
+++ b/sim_sock.c
@@ -163,6 +163,8 @@ typedef size_t socklen_t;
 typedef int (WSAAPI *getnameinfo_func) (const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags);
 static getnameinfo_func p_getnameinfo;
 
+#if !defined(AF_INET6) || defined(TEST_INFO_STUBS) || defined(_WIN32)
+
 static void    WSAAPI s_freeaddrinfo (struct addrinfo *ai)
 {
 struct addrinfo *a, *an;
@@ -384,6 +386,8 @@ if ((host) && (hostlen > 0)) {
 return 0;
 }
 
+#endif /* !defined(AF_INET6) || defined(TEST_INFO_STUBS) || defined(_WIN32) */
+
 #if defined(_WIN32) || defined(__CYGWIN__)
 
 #if !defined(IPV6_V6ONLY)           /* Older XP environments may not define IPV6_V6ONLY */
@@ -675,7 +679,7 @@ if (c != NULL) {
     bits = strtoul (c + 1, &c1, 10);
     if ((bits == 0) || (bits > 128) || (*c1 != '\0'))
         return status;
-    if ((c - validate_addr) > sizeof (v_cpy) - 1)
+    if ((size_t)(c - validate_addr) > sizeof (v_cpy) - 1)
         return status;
     memcpy (v_cpy, validate_addr, c - validate_addr);   /* Copy everything before the / */
     v_cpy[c - validate_addr] = '\0';                    /* NUL terminate the result */
@@ -701,7 +705,7 @@ while ((*acl != '\0') && !done) {
     permit = (*acl == '+');
     cc = strchr (acl, ',');
     if (cc != NULL) {
-        if ((cc - acl) > sizeof (rule))
+        if ((size_t)(cc - acl) > sizeof (rule))
             break;                  /* Too big - error */
         memcpy (rule, acl + 1, cc - (acl + 1));
         rule[cc - (acl + 1)] = '\0';