bug#26966: New Java bootstrap

[Ludovic Courtès]

Ricardo Wurmus <address@hidden> skribis:

> This patch series removes GCJ and bootstraps the JDK with Jikes.
>
> Up to now our Java bootstrap with GCJ involved nasty compromises:
>
> * GCJ depended on an iterative Java compiler in the form of a binary of
>   ECJ (the Eclipse compiler for Java)
>
> * The GCJ sources include pre-compiled Java .class files coming from
>   the GNU Classpath project.
>
> I only learned of the second of these problems when I expressed my
> sadness about the removal of GCJ and Andrew Haley replied that GCJ
> depended on binaries to a larger extent than I was aware of.
>
> Recently Ludo brought up Jikes on #guix and while it first looked like a
> much less capable compiler (only implementing a limited set of Java 1.5)
> it turned out to be enough to get a first bootstrap JDK built.  After
> some experimentation I managed to build a version of ECJ from source,
> which eventually led the way to a properly bootstrapped JDK with IcedTea.

Kudos for carrying it out, impressive piece of work!

I’m happy this will trim down the amount of opaque binaries our packages
rely on.

Ludo’.