[fedora-java] New file layout for nativified rpms

[Gary Benson]

Bryce McKinlay wrote:
> Gary Benson wrote:
> > If compatibility _is_ broken, will it fail gracefully?
> 
> libgcj 4.0.0 would crash if it saw a compiled class with an
> incompatible version ID, but this is fixed in 4.0.1 and 4.1. Now, we
> will silently refuse to load the class and fall back to the bytecode
> interpreter when a native-compiled class could not be loaded for
> some reason.
> 
> But, I'm not sure that this is really the most "graceful" behaviour
> - the user could easily be unaware that their .so did not load and
> wonder why performance is bad. Other alternatives we could consider
> include:
> 
> 1. Issue a warning before falling back to the bytecode interpreter
> 2. Throw a ClassFormatError/ClassNotFoundException/VerifyError

My vote would go for #1.

> Note that this will most likely happen when you try to run a newwer
> compiled class against an old runtime. In general, we will try to
> preserve backwards-compatibility so that old compiled classes will
> continue to work with new runtimes - although, as Tom points out, we
> don't yet guarantee it.

Cool.