diff --git a/src/openssl.c b/src/openssl.c
index 9dfc487..473337c 100644
--- a/src/openssl.c
+++ b/src/openssl.c
@@ -201,7 +201,7 @@ _libssh2_cipher_crypt(_libssh2_cipher_ctx * ctx,
     return ret == 1 ? 0 : 1;
 }
 
-#if LIBSSH2_AES_CTR && !HAVE_EVP_AES128_CTR
+#if defined(LIBSSH2_AES_CTR) && !defined(HAVE_EVP_AES128_CTR)
 
 #include <openssl/aes.h>
 
diff --git a/src/openssl.h b/src/openssl.h
index 3440410..3e0512b 100644
--- a/src/openssl.h
+++ b/src/openssl.h
@@ -198,7 +198,7 @@ int _libssh2_dsa_sha1_sign(libssh2_dsa_ctx * dsactx,
 #define _libssh2_cipher_aes256 EVP_aes_256_cbc
 #define _libssh2_cipher_aes192 EVP_aes_192_cbc
 #define _libssh2_cipher_aes128 EVP_aes_128_cbc
-#if HAVE_EVP_AES128_CTR
+#ifdef HAVE_EVP_AES128_CTR
 #define _libssh2_cipher_aes128ctr EVP_aes_128_ctr
 #define _libssh2_cipher_aes192ctr EVP_aes_192_ctr
 #define _libssh2_cipher_aes256ctr EVP_aes_256_ctr