Address a few code analysis warnings: uninitialized vars and undefined behavior

libdnet-stripped/src/addr.c

@@ -74,7 +74,7 @@ addr_cmp(const struct addr *a, const struct addr *b)
 	if ((k = b->addr_bits % 8) == 0)
 		return (0);
 
-	k = ~0 << (8 - k);
+	k = (~(unsigned int)0) << (8 - k);
 	i = b->addr_data8[j] & k;
 	j = a->addr_data8[j] & k;
 	
@@ -449,7 +449,7 @@ addr_btom(uint16_t bits, void *mask, size_t size)
 			return (-1);
 		}
 		*(uint32_t *)mask = bits ?
-		    htonl(~0 << (IP_ADDR_BITS - bits)) : 0;
+		    htonl(~(uint32_t)0 << (IP_ADDR_BITS - bits)) : 0;
 	} else {
 		if (size * 8 < bits) {
 			errno = EINVAL;

libdnet-stripped/src/intf-win32.c

@@ -505,7 +505,7 @@ intf_loop(intf_t *intf, intf_handler callback, void *arg)
 	IP_ADAPTER_ADDRESSES *a;
 	struct intf_entry *entry;
 	u_char ebuf[1024];
-	int ret;
+	int ret = 0;
 
 	if (_refresh_tables(intf) < 0)
 		return (-1);

nbase/nbase_addrset.c

@@ -150,7 +150,7 @@ static void trie_free(struct trie_node *curr)
   /* Since we descend only down one side, we at most accumulate one tree's-depth, or 128.
    * Add 4 for safety to account for special root node and special empty stack position 0.
    */
-  struct trie_node *stack[128+4];
+  struct trie_node *stack[128+4] = {NULL};
   int i = 1;
 
   while (i > 0 && curr != NULL && curr != TRIE_NODE_TRUE) {

nsock/src/nsock_write.c

@@ -191,7 +191,7 @@ nsock_event_id nsock_printf(nsock_pool ms_pool, nsock_iod ms_iod,
       va_start(ap,format);
       res2 = Vsnprintf(buf2, buf2size, format, ap);
       va_end(ap);
-      if (res2 < 0 || res2 >= buf2size) {
+      if (res2 < 0 || (size_t) res2 >= buf2size) {
         free(buf2);
         buf2 = NULL;
       } else