Options for re-adding gcj

Options for re-adding gcj

[Zopolis0]

Over the past few months I have been working on re-adding gcj back into
gcc, as the fundamental issue holding it back (the need to create an
open-source implementation of java from the ground up) has since been
solved by the opening of the JDK.

Unfortunately, as the old gcj code is several years old, it does not work
nicely with the current code and is largely incomplete. I have gotten it
into a state where gcc will compile with default options, unless you
forcibly enable java.

The issues I am now encountering are far beyond my skill level, and would
require someone with much more familiarity with the gcc tree than me and
general coding experience.

This leaves a few options for creating a functional Java compiler using the
OpenJDK.

1. Add the code in its current state to the current gcc tree, and have it
gradually get repaired to a state of feature parity with when it was
removed, then replace the Classpath with the OpenJDK. (There are a variety
of options for this as well, but I aim to implement it in a way similar to
C/C++ standards.)

2. Try and identify the breaking changes, speak to the people who made them
(or other people familiar with the relevant areas of the gcc tree) and get
their assistance in extending those changes to the gcj source files.

3. Replace Classpath with OpenJDK in GCC 6, (following the same C/C++
standards idea as above), as this would not require any changes to source
files and would work seamlessly. However, this is obviously not optimal,
and I would prefer to avoid it.

Which option do people think is the best?