FULL PRODUCT VERSION :
java version "1.6.0"
Java(TM) SE Runtime Environment (build 1.6.0-b105)
Java HotSpot(TM) 64-Bit Server VM (build 1.6.0-b105, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux hssa1.aoa.twosigma.com 2.6.18-ts1 #1 SMP PREEMPT Fri Sep 29 14:06:04 GMT 2006 x86_64 x86_64 x86_64 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
successive invocations of Math.log() produce inconsistent results (possibly depending on compilation because -Xint or -XX:CompleThreshold=0 always produces consistent results). The number of iterations in the actual result varies.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
$ javac LogTest.java
$ java -cp . LogTest

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
n=17197.0
SUCCESS!
ACTUAL -
n=17197.0
ERROR after 43235 iterations:
previous value: 9.7524902289842 (40238146663817e8)
 current value: 9.752490228984199 (40238146663817e7)


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public class LogTest {

    public static void main(String[] args)
    {
        double n = Integer.parseInt("17197");
        System.out.println("n=" + n);
        double d = Math.log(n);
        for (int i = 0; i < 100000; i++) {
            double e = Math.log(n);
            if (e != d) {
                System.err.println("ERROR after " + i + " iterations:\n" +
                   "previous value: " + d + " (" +
                   Long.toHexString(Double.doubleToLongBits(d)) + ")\n" +
                   " current value: " + e + " (" +
                   Long.toHexString(Double.doubleToLongBits(e)) + ")");
                System.exit(1);
            }
        }
        System.err.println("SUCCESS!");
        System.exit(0);
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
run with -Xint -XXCompilerThreshold=0 produces the expected result, on the other hand, is that a complete fix? Are floating point results reliable?