diff --git a/lib/accelerated/x86/aes-xts-x86-aesni.c b/lib/accelerated/x86/aes-xts-x86-aesni.c
index 3371d08..b904cbf 100644
--- a/lib/accelerated/x86/aes-xts-x86-aesni.c
+++ b/lib/accelerated/x86/aes-xts-x86-aesni.c
@@ -72,7 +72,7 @@ x86_aes_xts_cipher_setkey(void *_ctx, const void *userkey, size_t keysize)
 
 	/* Check key block according to FIPS-140-2 IG A.9 */
 	if (_gnutls_fips_mode_enabled()){
-		if (safe_memcmp(key, key + (keysize / 2), keysize / 2) == 0) {
+		if (gnutls_memcmp(key, key + (keysize / 2), keysize / 2) == 0) {
 			_gnutls_switch_lib_state(LIB_STATE_ERROR);
 			return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);
 		}
diff --git a/lib/ext/pre_shared_key.c b/lib/ext/pre_shared_key.c
index fef67d3..240be21 100644
--- a/lib/ext/pre_shared_key.c
+++ b/lib/ext/pre_shared_key.c
@@ -650,7 +650,7 @@ static int server_recv_params(gnutls_session_t session,
 	}
 
 	if (_gnutls_mac_get_algo_len(prf) != binder_recvd.size ||
-	    safe_memcmp(binder_value, binder_recvd.data, binder_recvd.size)) {
+	    gnutls_memcmp(binder_value, binder_recvd.data, binder_recvd.size)) {
 		gnutls_assert();
 		ret = GNUTLS_E_RECEIVED_ILLEGAL_PARAMETER;
 		goto fail;
diff --git a/lib/mem.h b/lib/mem.h
index dc838a2..d3eea97 100644
--- a/lib/mem.h
+++ b/lib/mem.h
@@ -35,15 +35,6 @@ char *_gnutls_strdup(const char *);
 
 unsigned _gnutls_mem_is_zero(const uint8_t *ptr, unsigned size);
 
-/* To avoid undefined behavior when s1 or s2 are null and n = 0 */
-inline static
-int safe_memcmp(const void *s1, const void *s2, size_t n)
-{
-	if (n == 0)
-		return 0;
-	return memcmp(s1, s2, n);
-}
-
 #define zrelease_mpi_key(mpi) if (*mpi!=NULL) { \
 		_gnutls_mpi_clear(*mpi); \
 		_gnutls_mpi_release(mpi); \
diff --git a/lib/nettle/cipher.c b/lib/nettle/cipher.c
index 69ed702..93afca2 100644
--- a/lib/nettle/cipher.c
+++ b/lib/nettle/cipher.c
@@ -396,7 +396,7 @@ _xts_aes128_set_encrypt_key(struct xts_aes128_key *xts_key,
 			    const uint8_t *key)
 {
 	if (_gnutls_fips_mode_enabled() &&
-	    safe_memcmp(key, key + AES128_KEY_SIZE, AES128_KEY_SIZE) == 0)
+	    gnutls_memcmp(key, key + AES128_KEY_SIZE, AES128_KEY_SIZE) == 0)
 		_gnutls_switch_lib_state(LIB_STATE_ERROR);
 
 	xts_aes128_set_encrypt_key(xts_key, key);
@@ -407,7 +407,7 @@ _xts_aes128_set_decrypt_key(struct xts_aes128_key *xts_key,
 			    const uint8_t *key)
 {
 	if (_gnutls_fips_mode_enabled() &&
-	    safe_memcmp(key, key + AES128_KEY_SIZE, AES128_KEY_SIZE) == 0)
+	    gnutls_memcmp(key, key + AES128_KEY_SIZE, AES128_KEY_SIZE) == 0)
 		_gnutls_switch_lib_state(LIB_STATE_ERROR);
 
 	xts_aes128_set_decrypt_key(xts_key, key);
@@ -418,7 +418,7 @@ _xts_aes256_set_encrypt_key(struct xts_aes256_key *xts_key,
 			    const uint8_t *key)
 {
 	if (_gnutls_fips_mode_enabled() &&
-	    safe_memcmp(key, key + AES256_KEY_SIZE, AES256_KEY_SIZE) == 0)
+	    gnutls_memcmp(key, key + AES256_KEY_SIZE, AES256_KEY_SIZE) == 0)
 		_gnutls_switch_lib_state(LIB_STATE_ERROR);
 
 	xts_aes256_set_encrypt_key(xts_key, key);
@@ -429,7 +429,7 @@ _xts_aes256_set_decrypt_key(struct xts_aes256_key *xts_key,
 			    const uint8_t *key)
 {
 	if (_gnutls_fips_mode_enabled() &&
-	    safe_memcmp(key, key + AES256_KEY_SIZE, AES256_KEY_SIZE) == 0)
+	    gnutls_memcmp(key, key + AES256_KEY_SIZE, AES256_KEY_SIZE) == 0)
 		_gnutls_switch_lib_state(LIB_STATE_ERROR);
 
 	xts_aes256_set_decrypt_key(xts_key, key);
diff --git a/lib/tls13/finished.c b/lib/tls13/finished.c
index 35ab87f..4cc1a84 100644
--- a/lib/tls13/finished.c
+++ b/lib/tls13/finished.c
@@ -112,7 +112,7 @@ int _gnutls13_recv_finished(gnutls_session_t session)
 #if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
 # warning This is unsafe for production builds
 #else
-	if (safe_memcmp(verifier, buf.data, buf.length) != 0) {
+	if (gnutls_memcmp(verifier, buf.data, buf.length) != 0) {
 		gnutls_assert();
 		ret = GNUTLS_E_ERROR_IN_FINISHED_PACKET;
 		goto cleanup;
diff --git a/lib/x509/x509.c b/lib/x509/x509.c
index 2091f3a..2b68fe4 100644
--- a/lib/x509/x509.c
+++ b/lib/x509/x509.c
@@ -360,7 +360,8 @@ static int compare_sig_algorithm(gnutls_x509_crt_t cert)
 	}
 
 	if (empty1 != empty2 ||
-	    sp1.size != sp2.size || safe_memcmp(sp1.data, sp2.data, sp1.size) != 0) {
+	    sp1.size != sp2.size ||
+	    (sp1.size > 0 && memcmp(sp1.data, sp2.data, sp1.size) != 0)) {
 		gnutls_assert();
 		ret = GNUTLS_E_CERTIFICATE_ERROR;
 		goto cleanup;