diff --git a/src/common/common.c b/src/common/common.c
index ce714652..aa942abd 100644
--- a/src/common/common.c
+++ b/src/common/common.c
@@ -30,6 +30,7 @@
 #include <netinet/ip.h>
 #include <poll.h>
 #include <limits.h>
+#include <assert.h>
 #include <nettle/sha1.h>
 #include "common.h"
 #include "defs.h"
@@ -254,7 +255,8 @@ ssize_t force_read(int sockfd, void *buf, size_t len)
 		if (ret == -1) {
 			if (errno != EAGAIN && errno != EINTR)
 				return ret;
-		} else if (ret == 0 && left != 0) {
+		} else if (ret == 0) {
+			assert(left != 0); /* ensured by the while */
 			errno = ENOENT;
 			return -1;
 		}
@@ -295,7 +297,8 @@ ssize_t force_read_timeout(int sockfd, void *buf, size_t len, unsigned sec)
 		if (ret == -1) {
 			if (errno != EAGAIN && errno != EINTR)
 				return ret;
-		} else if (ret == 0 && left != 0) {
+		} else if (ret == 0) {
+			assert(left != 0);
 			errno = ENOENT;
 			return -1;
 		}
diff --git a/src/ip-util.c b/src/ip-util.c
index 224a0f12..48a48bf6 100644
--- a/src/ip-util.c
+++ b/src/ip-util.c
@@ -21,6 +21,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <talloc.h>
+#include <assert.h>
 /* for inet_ntop */
 #include <arpa/inet.h>
 #include <syslog.h>
@@ -218,7 +219,8 @@ char *human_addr2(const struct sockaddr *sa, socklen_t salen,
 	if (salen == sizeof(struct sockaddr_in6)) {
 		port = (unsigned)ntohs(((struct sockaddr_in6*)sa)->sin6_port);
 
-		if (full != 0 && port != 0 && buflen > 0) {
+		if (full != 0 && port != 0) {
+			assert(buflen > 0); /* already checked, but to avoid regression */
 			*buf = '[';
 			buf++;
 			buflen--;