Compiler safepoints do not work on SPARC.
Run the appended program with following commandline
and it will hang (use server VM)
java -Xcomp -verbose:gc sf

Run it with following commandline and it terminates properly:
java -Xint -verbose:gc sf

The program hangs if the method loop is compiled because
the runtime cannot properly suspend the endless loop.
I have verified that Compiler 2 (server) is
emitting safepoint information.



----------------
public class sf {
        static public boolean _xx = true;

public static void main(String[] args) {
new Srdjan().start();
}

public void start() {
new TesterThread().start();
new GCThread().start();
}

class TesterThread extends Thread {

                // trick compiler 2 in believing that this is not and endless loop
                public void loop (int n) {
long counter = 0;
while (_xx) {
if (n == 0) {
                                  _xx = false;
                                }
}
                }
public void run () {
System.out.println("Start loop");
                        loop(3);
}
}

class GCThread extends Thread {
public void run () {
System.out.println("Starting GC loop");
long counter = 0;
while (true) {
try { sleep(250); } catch (InterruptedException ix) {}
System.gc();
                                counter++;
                                if (counter == 10) {
                                  _xx = false;
                                  return;
                                }
}
}
}
}