--- /dev/null
+commit 98156e90e1e83133a6a6a020db8e7333ada6156b
+Author: Steffan Karger <steffan@karger.me>
+Date: Tue Dec 2 21:42:00 2014 +0100
+
+ Really fix '--cipher none' regression
+
+ ... by not incorrectly hinting to the compiler the function argument of
+ cipher_kt_mode_{cbc,ofb_cfb}() is nonnull, since that no longer is the
+ case.
+
+ Verified the fix on Debian Wheezy, one of the platforms the reporter in
+ trac #473 mentions with a compiler that would optimize out the required
+ checks.
+
+ Also add a testcase for --cipher none to t_lpback, to prevent further
+ regressions.
+
+ Signed-off-by: Steffan Karger <steffan@karger.me>
+ Acked-by: Gert Doering <gert@greenie.muc.de>
+ Message-Id: <1417552920-31770-1-git-send-email-steffan@karger.me>
+ URL: http://article.gmane.org/gmane.network.openvpn.devel/9300
+ Signed-off-by: Gert Doering <gert@greenie.muc.de>
+
+--- a/src/openvpn/crypto_backend.h
++++ b/src/openvpn/crypto_backend.h
+@@ -237,8 +237,7 @@ int cipher_kt_mode (const cipher_kt_t *c
+ *
+ * @return true iff the cipher is a CBC mode cipher.
+ */
+-bool cipher_kt_mode_cbc(const cipher_kt_t *cipher)
+- __attribute__((nonnull));
++bool cipher_kt_mode_cbc(const cipher_kt_t *cipher);
+
+ /**
+ * Check if the supplied cipher is a supported OFB or CFB mode cipher.
+@@ -247,8 +246,7 @@ bool cipher_kt_mode_cbc(const cipher_kt_
+ *
+ * @return true iff the cipher is a OFB or CFB mode cipher.
+ */
+-bool cipher_kt_mode_ofb_cfb(const cipher_kt_t *cipher)
+- __attribute__((nonnull));
++bool cipher_kt_mode_ofb_cfb(const cipher_kt_t *cipher);
+
+
+ /**
+--- a/tests/t_lpback.sh
++++ b/tests/t_lpback.sh
+@@ -35,6 +35,9 @@ CIPHERS=$(${top_builddir}/src/openvpn/op
+ # GD, 2014-07-06 do not test RC5-* either (fails on NetBSD w/o libcrypto_rc5)
+ CIPHERS=$(echo "$CIPHERS" | egrep -v '^(DES-EDE3-CFB1|DES-CFB1|RC5-)' )
+
++# Also test cipher 'none'
++CIPHERS=${CIPHERS}$(printf "\nnone")
++
+ "${top_builddir}/src/openvpn/openvpn" --genkey --secret key.$$
+ set +e
+