diff --git a/unittests/kex/test_kex.c b/unittests/kex/test_kex.c
index 8d9b047..92bffa1 100644
--- a/unittests/kex/test_kex.c
+++ b/unittests/kex/test_kex.c
@@ -28,7 +28,7 @@ do_send_and_receive(struct ssh *from, struct ssh *to)
 {
 	u_char type;
 	size_t len;
-	char *buf;
+	const u_char *buf;
 	int r;
 
 	for (;;) {
diff --git a/unittests/sshbuf/test_sshbuf_fuzz.c b/unittests/sshbuf/test_sshbuf_fuzz.c
index 2eeeb80..8bf5892 100644
--- a/unittests/sshbuf/test_sshbuf_fuzz.c
+++ b/unittests/sshbuf/test_sshbuf_fuzz.c
@@ -113,8 +113,7 @@ sshbuf_fuzz_tests(void)
 				goto fuzz_reserve;
 			}
 		}
-		dp = sshbuf_ptr(p1);
-		ASSERT_PTR_NE(dp, NULL);
+		ASSERT_PTR_NE(sshbuf_ptr(p1), NULL);
 		ASSERT_SIZE_T_LE(sshbuf_max_size(p1), 16 * 1024);
 	}
 	ASSERT_PTR_NE(sshbuf_ptr(p1), NULL);
diff --git a/unittests/sshkey/common.c b/unittests/sshkey/common.c
index 6728858..9944ec4 100644
--- a/unittests/sshkey/common.c
+++ b/unittests/sshkey/common.c
@@ -47,7 +47,7 @@ struct sshbuf *
 load_text_file(const char *name)
 {
 	struct sshbuf *ret = load_file(name);
-	u_char *p;
+	const u_char *p;
 
 	/* Trim whitespace at EOL */
 	for (p = sshbuf_ptr(ret); sshbuf_len(ret) > 0;) {