Instead, segregate features and produce many patches. Use as late code as possible, for the original code. Write ChangeLog entries. Make patches in unified diff format. Don't make patches reversely.
Reverse patches are difficult to read and use.
Be careful enough of the license term and the copyright. And, if you copy code written by others, you must not ignore their copyrights. Feel free to ask GRUB maintainers, whenever you are not sure what you should do. If your patch is too large to send in e-mail, put it at somewhere we can see. Usually, you shouldn't send e-mail over 20K. Go to the first , previous , next , last section, table of contents .