So you want to add something
(and not break the build) ...

Adding files follows a very different procedure on each of the three Mozilla platforms. Engineers working on one platform often get confused and miss steps when checking in new files or directories, thus breaking the build for platforms other than their own.

This document is intended as a guide to help prevent that from happening.

The most important piece of advice is:
Don't forget to check Tinderbox after you check in!

UNIX (Autoconf build)

• If you add a file or a subdirectory to makefile.win, don't forget to add it to Makefile.in as well.
• If you add a new directory to the build, you have to add an entry for its Makefile in the directory list in mozilla/allmakefiles.sh, as well as adding the directory to the list of subdirs in ../Makefile.in.

Windows

• Change the makefile.win in the appropriate directories.

Mac

• To export a new include file, you can add the file name to the list in the MANIFEST file.
• To add a new C++ file or a new directory, you currently need to talk to a Mac person to get the new stuff added to the project. Scripts are being worked on which will allow files to be added from non-Mac machines.