diff --git a/tnt/tnt_auth.c b/tnt/tnt_auth.c
index f4d6047..ffb490b 100644
--- a/tnt/tnt_auth.c
+++ b/tnt/tnt_auth.c
@@ -76,11 +76,11 @@ tnt_auth_raw(struct tnt_stream *s, const char *user, int ulen,
 	v[3].iov_len  = ulen;
 	body_start = data;
 	data = mp_encode_uint(data, TNT_TUPLE);
+	char salt[64], scramble[TNT_SCRAMBLE_SIZE];
 	if (!guest) {
 		data = mp_encode_array(data, 2);
 		data = mp_encode_str(data, "chap-sha1", strlen("chap-sha1"));
 		data = mp_encode_strl(data, TNT_SCRAMBLE_SIZE);
-		char salt[64], scramble[TNT_SCRAMBLE_SIZE];
 		base64_decode(base64_salt, TNT_SALT_SIZE, salt, 64);
 		tnt_scramble_prepare(scramble, salt, pass, plen);
 		v[5].iov_base = scramble;
diff --git a/tnt/tnt_io.c b/tnt/tnt_io.c
index f0835fc..a06b500 100644
--- a/tnt/tnt_io.c
+++ b/tnt/tnt_io.c
@@ -68,7 +68,8 @@ tnt_io_resolve(struct sockaddr_in *addr,
 	addr->sin_family = AF_INET;
 	addr->sin_port = htons(port);
 	struct addrinfo *addr_info = NULL;
-	if (getaddrinfo(hostname, NULL, NULL, &addr_info) == 0) {
+	if (getaddrinfo(hostname, NULL, NULL, &addr_info) == 0 &&
+	    addr_info != NULL) {
 		memcpy(&addr->sin_addr,
 		       (void*)&((struct sockaddr_in *)addr_info->ai_addr)->sin_addr,
 		       sizeof(addr->sin_addr));
diff --git a/tnt/tnt_object.c b/tnt/tnt_object.c
index cd83d90..da659ce 100644
--- a/tnt/tnt_object.c
+++ b/tnt/tnt_object.c
@@ -332,7 +332,7 @@ ssize_t tnt_object_vformat(struct tnt_stream *s, const char *fmt, va_list vl)
 			if ((rv = tnt_object_add_map(s, 0)) == -1)
 				return -1;
 			result += rv;
-		} if (f[0] == ']' || f[0] == '}') {
+		} else if (f[0] == ']' || f[0] == '}') {
 			if ((rv = tnt_object_container_close(s)) == -1)
 				return -1;
 			result += rv;
diff --git a/tnt/tnt_request.c b/tnt/tnt_request.c
index 0f84a6b..faa524c 100644
--- a/tnt/tnt_request.c
+++ b/tnt/tnt_request.c
@@ -312,11 +312,12 @@ tnt_request_writeout(struct tnt_stream *s, struct tnt_request *req,
 		v[v_sz++].iov_len = pos - begin;
 	}
 	mp_encode_map(map, nd);
-	size_t plen = 0; nd = 0;
+
+	size_t plen = 0;
 	for (int i = 1; i < v_sz; ++i) plen += v[i].iov_len;
-	nd = mp_sizeof_luint32(plen);
-	v[0].iov_base -= nd;
-	v[0].iov_len  += nd;
+	size_t hlen = mp_sizeof_luint32(plen);
+	v[0].iov_base -= hlen;
+	v[0].iov_len  += hlen;
 	mp_encode_luint32(v[0].iov_base, plen);
 	ssize_t rv = s->writev(s, v, v_sz);
 	if (rv == -1)
diff --git a/tnt/tnt_schema.c b/tnt/tnt_schema.c
index 5dd5d03..ffe4bb8 100644
--- a/tnt/tnt_schema.c
+++ b/tnt/tnt_schema.c
@@ -300,7 +300,7 @@ void tnt_schema_flush(struct tnt_schema *obj) {
 
 void tnt_schema_free(struct tnt_schema *obj) {
 	if (obj == NULL)
-		return NULL;
+		return;
 	tnt_schema_space_free(obj->space_hash);
 	mh_assoc_delete(obj->space_hash);
 }