From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter <peter@rimuhosting.com>
Subject: Re: Java Problems
Date: Sat, 13 Aug 2005 08:17:59 +1200
Message-ID: <42FD03F7.4080901@rimuhosting.com>
References: <OF8DAF4393.0622A224-ON8525705B.004B18C0-8525705B.004B6D78@us.ibm.com>
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To: Reuben Kabel <kabel@us.ibm.com>
Cc: xen-devel@lists.xensource.com
List-Id: xen-devel@lists.xenproject.org

Hi.

I don't have a 2.0.7 to test on at the moment.  I will try again when I do.

I got rid of the object allocation inside the loop.  And I retested.  I 
don't hit the problem with int's on the call stack.  I do hit the 
problem with floats and doubles.

The problem is quite easily reproducible (for me).  Is someone there 
with knowledge of register/stack handle able to take a look with gdb or 
which ever tool you use?

Regards, Peter
http://rimuhosting.com - Xen VPS Hosting


public class FillTest {
     public static void main(String[] args) {
         System.out.println("Starting");
         foo f = new foo();
         for (int i = 0;i<100000000; i++) {
             f.iter = i;
             f.test();
         }
     }
     public static class foo {
         int iter;
         float f = 0.75f;
         int i=1;
         double d = 0.75d;
         void test() {
             testI(i);
             testD(d);
             test(f);
         }
         void test(float f1) {
             if(f1!=f) {
                 throw new RuntimeException("float value mismatch: " + 
f1 + " vs " + f + " at iteration " + iter);
             }
         }
         void testI(int fi) {
             if(fi!=i) {
                 throw new RuntimeException("int value mismatch: " + fi 
+ " vs " + i + " at iteration " + iter);
             }
         }
         void testD(double fd) {
             if(fd!=d) {
                 throw new RuntimeException("double value mismatch: " + 
fd + " vs " + d + " at iteration " + iter);
             }
         }
     }
}


Starting
Exception in thread "main" java.lang.RuntimeException: double value 
mismatch: 0.                                      75 vs 0.75 at 
iteration 3981054
         at FillTest$foo.testD(FillTest.java:33)
         at FillTest$foo.test(FillTest.java:18)
         at FillTest.main(FillTest.java:8)
Starting
Starting
Exception in thread "main" java.lang.RuntimeException: double value 
mismatch: Na                                      N vs 0.75 at iteration 
33238270
         at FillTest$foo.testD(FillTest.java:33)
         at FillTest$foo.test(FillTest.java:18)
         at FillTest.main(FillTest.java:8)
Starting
Exception in thread "main" java.lang.RuntimeException: double value 
mismatch: 0.75                                     vs 0.75 at iteration 
43731162
         at FillTest$foo.testD(FillTest.java:33)
         at FillTest$foo.test(FillTest.java:18)
         at FillTest.main(FillTest.java:8)
Starting
Exception in thread "main" java.lang.RuntimeException: double value 
mismatch: 0.75 vs 0.75 at iteration 26104068
         at FillTest$foo.testD(FillTest.java:33)
         at FillTest$foo.test(FillTest.java:18)
         at FillTest.main(FillTest.java:8)
Starting
Exception in thread "main" java.lang.RuntimeException: double value 
mismatch: 0.75 vs 0.75 at iteration 350370
         at FillTest$foo.testD(FillTest.java:33)
         at FillTest$foo.test(FillTest.java:18)
         at FillTest.main(FillTest.java:8)
Starting


Reuben Kabel wrote:
> 
> 
> 
> Does the following code exhibit the same problem? I've modified it so it
> doesn't try to allocate many foo instances within the loop.
>