Things libgcj hackers should know --------------------------------- If you want to hack on the libgcj files you need to be aware of the following things. There are probably lots of other things that should be explained in this HACKING file. Please add them if you discover them :) -- A lot of the standard library files come from the GNU Classpath project. <http://www.gnu.org/software/classpath/> The libgcj and Classpath project have officially merged, but the merge is not yet complete. Our eventual goal is for Classpath to be an upstream source provider for libgcj, however it will be some time before this becomes reality: libgcj and Classpath have different implementations of many core java classes. In order to merge them, we need to select the best (most efficient, cleanest) implementation of each method/class/package, resolve any conflicts created by the merge, and test the final result. The merged files can be recognized by the standard Classpath copyright comments at the top of the file. If you make changes to these files then you should also check in the fix to Classpath. For small changes it may be easier to send a patch to the classpath mailinglist. For large changes, if you have direct write access to the libgcj tree, then you will also need to get a Classpath account and do the work yourself. <http://mail.gnu.org/mailman/listinfo/classpath/> <mailto:classpath@gnu.org> If you merge a libgcj class with a classpath class then you must update the copyright notice at the top of the file so others can see that this is a shared libgcj/classpath file. -- If you need to add new java files to libgcj then you have to edit the Makefile.am file in the top (libjava) directory. And run automake. Tom Tromey adds: If you add a class to java.lang, java.io, or java.util (including sub-packages, like java.lang.ref). * Edit gcj/javaprims.h * Go to the `namespace java' line, and delete that entire block (the entire contents of the namespace) * Then insert the output of `perl ../scripts/classes.pl' into the file at that point. If you're generating a patch there is a program you can get to do an offline `cvs add' (it will fake an `add' if you don't have write permission yet). Then you can use `cvs diff -N' to generate the patch. See http://www.red-bean.com/cvsutils/