GCJ information

Tue Dec 11 22:03:00 GMT 2001

>>>>> "Bose" == Ghanta, Bose <bose.ghanta@stratus.com> writes:

Bose> We are now looking into a compiler for Java language. I would
Bose> appreciate if you can provide me information on GCJ and how it
Bose> compares to Sun Java 1.3 release and Hotspot. Also information
Bose> on features improvements in GCJ. What is the best GCJ release
Bose> we can bring up?
gcj has most language features, but is still missing `strictfp'.
libgcj has most of the core libraries. By and large they are close to
1.3 compatibility, I think. Some things are missing, most notably
AWT. Some parts aren't well tested.
There is a bytecode interpreter but it is very slow. There is no
JIT. There are some missing VM-level features: stack overflow
detection doesn't work and some security features are missing.
As far as performance goes, I don't know. I don't generally run
benchmarks very often. I imagine for certain micro-benchmarks we
would do very well.
The best gcj release depends a lot on your needs. On the one hand,
the current cvs trunk has the most features. That is where all the
development happens -- and, since gcj is still actively developed, a
lot has changed since the most recent stable release (3.0.x -- I
forget if x==1 or x==2). On the other hand, the cvs trunk
occasionally is broken in various ways. So it isn't always a reliable
choice. When 3.1 comes out, that will be the gcj compiler of choice.
However, that is still some months away.
Tom