In the attached *.dds texture, we were expecting that Devil would report that it had 10 mipmaps, but it reports 9. The Microsoft DirectX Texture Tool reports 10. Your documentation in section 9.1 says that it will create "All mipmap levels down to 1x1". Yet, getting the IL_NUM_MIPMAPS integer returns 9.
Is this a bug?
If I make our code pretend that DevIl returned one additional mipmap, the byte data for this texture crashes a later call to glCompressedTexImage2DARB. So, I'm guessing that DevIl does not actually generate the 1x1 mipmap.