Add final attribute to many classes

In some cases this can offer better optimization, via devirtualization.
And it lets the user know the class is not intended for derivation.

Some discussion in GH #402

1 files changed, 1 insertions, 1 deletions

diff --git a/src/lib/stream/rc4/rc4.h b/src/lib/stream/rc4/rc4.h
index c8c81d1a2..db1726a18 100644
--- a/src/lib/stream/rc4/rc4.h
+++ b/src/lib/stream/rc4/rc4.h
@@ -16,7 +16,7 @@ namespace Botan {
 /**
 * RC4 stream cipher
 */
-class BOTAN_DLL RC4 : public StreamCipher
+class BOTAN_DLL RC4 final : public StreamCipher
    {
    public:
       void cipher(const byte in[], byte out[], size_t length) override;