--- a/libpurple/cipher.c Mon Sep 30 14:08:06 2013 +0530 +++ b/libpurple/cipher.c Tue Oct 01 03:24:42 2013 +0530 @@ -145,7 +145,7 @@ guchar digest[BUF_LEN * 4]; size_t digest_size, n; - g_return_val_if_fail(cipher, FALSE); + g_return_val_if_fail(PURPLE_IS_CIPHER(cipher), FALSE); g_return_val_if_fail(digest_s, FALSE); digest_size = purple_cipher_get_digest_size(cipher);