--- a/src/Common/CpuCore.c
+++ b/src/Common/CpuCore.c
@@ -96,7 +96,7 @@
 		derive_key_whirlpool (  word, wordlength+1, salt, PKCS5_SALT_SIZE, 1000, headerKey, cpu_GetMaxPkcs5OutSize ());
 	else{
 		perror("Key derivation function not supported");
-		return;
+		return 0;
 	}
 
 	value=cpu_Xts(encryptionAlgorithm,encryptedHeader,headerKey,cpu_GetMaxPkcs5OutSize(), masterKey, &length);