diff --git a/crypto/aes/aes_cbc.c b/crypto/aes/aes_cbc.c
index d65701b5f..f1ea40ab0 100644
--- a/crypto/aes/aes_cbc.c
+++ b/crypto/aes/aes_cbc.c
@@ -49,7 +49,13 @@
  *
  */
 
+#ifndef AES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
 #include <assert.h>
+
 #include <openssl/aes.h>
 #include "aes_locl.h"
 
diff --git a/crypto/aes/aes_cfb.c b/crypto/aes/aes_cfb.c
index 41c2a5ec3..9b569dda9 100644
--- a/crypto/aes/aes_cfb.c
+++ b/crypto/aes/aes_cfb.c
@@ -105,7 +105,13 @@
  * [including the GNU Public Licence.]
  */
 
+#ifndef AES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
 #include <assert.h>
+
 #include <openssl/aes.h>
 #include "aes_locl.h"
 
diff --git a/crypto/aes/aes_core.c b/crypto/aes/aes_core.c
index 937988dd8..ea884f6f9 100644
--- a/crypto/aes/aes_core.c
+++ b/crypto/aes/aes_core.c
@@ -28,7 +28,13 @@
 /* Note: rewritten a little bit to provide error control and an OpenSSL-
    compatible API */
 
+#ifndef AES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
 #include <assert.h>
+
 #include <stdlib.h>
 #include <openssl/aes.h>
 #include "aes_locl.h"
diff --git a/crypto/aes/aes_ctr.c b/crypto/aes/aes_ctr.c
index 142ca4a14..59088499a 100644
--- a/crypto/aes/aes_ctr.c
+++ b/crypto/aes/aes_ctr.c
@@ -49,7 +49,13 @@
  *
  */
 
+#ifndef AES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
 #include <assert.h>
+
 #include <openssl/aes.h>
 #include "aes_locl.h"
 
diff --git a/crypto/aes/aes_ecb.c b/crypto/aes/aes_ecb.c
index 1cb2e07d3..28aa561c2 100644
--- a/crypto/aes/aes_ecb.c
+++ b/crypto/aes/aes_ecb.c
@@ -49,7 +49,13 @@
  *
  */
 
+#ifndef AES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
 #include <assert.h>
+
 #include <openssl/aes.h>
 #include "aes_locl.h"
 
diff --git a/crypto/aes/aes_ofb.c b/crypto/aes/aes_ofb.c
index e33bdaea2..f358bb39e 100644
--- a/crypto/aes/aes_ofb.c
+++ b/crypto/aes/aes_ofb.c
@@ -105,7 +105,13 @@
  * [including the GNU Public Licence.]
  */
 
+#ifndef AES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
 #include <assert.h>
+
 #include <openssl/aes.h>
 #include "aes_locl.h"