diff --git a/library/cmac.c b/library/cmac.c
index b2fe713..9fcb439 100644
--- a/library/cmac.c
+++ b/library/cmac.c
@@ -765,7 +765,7 @@
                               int block_size,
                               int num_tests )
 {
-    int i, ret;
+    int i, ret = 0;
     mbedtls_cipher_context_t ctx;
     const mbedtls_cipher_info_t *cipher_info;
     unsigned char K1[MBEDTLS_CIPHER_BLKSIZE_MAX];
@@ -847,7 +847,7 @@
                                  int num_tests )
 {
     const mbedtls_cipher_info_t *cipher_info;
-    int i, ret;
+    int i, ret = 0;
     unsigned char output[MBEDTLS_CIPHER_BLKSIZE_MAX];
 
     cipher_info = mbedtls_cipher_info_from_type( cipher_type );