Bug 7181756

[Adam Hawthorne]

Hi Kris,

Thanks for the update - I hadn't noticed 7u9 was released until your
response.

Regards,

Adam

On Tue, Oct 16, 2012 at 5:39 PM, Krystal Mo <krystal.mo at oracle.com> wrote:

>  Hi Adam,
>
> I'm working on it and will send the fix out for review this week. Sorry
> for not reacting promptly enough for this issue.
>
> The latest CPU releases of JDK should have temporarily disabled the
> faulting optimizations already.
>
> Regards,
> Kris
>
>
> On 2012/10/17 5:31, Adam Hawthorne wrote:
>
> Hi all,
>
>  Apologies for a -use question on a -dev list, but I couldn't find the
> -use list ...
>
>  A colleague of mine just ran into this bug:
>
>  http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7181756
> "Non-zero initial values in a byte array - regression in Java 7"
>
>  This seems like a pretty serious issue; a subsequent search found four
> instances in our own source code that could potentially trigger the issue.
>  Has it seen any attention?  We did some testing and it appears it was
> introduced with hs23 in 7u4.
>
>  A simple test (based on the sample in the bug) will reproduce:
>
>
>  import java.util.*;
>
>  class TestBug2 {
>     public static void main(String[] argv) {
>         TestBug2 bug = new TestBug2();
>         for (int i = 0; i < 10000000; ++i) {
>             bug.testBug(i);
>         }
>     }
>
>      private void testBug(int iter) {
>         byte[] buf8 = new byte[8];
>         for (byte b : buf8) {
>             if (b != 0)
>                 throw new Error(iter + ": " + b);
>         }
>         Arrays.fill(buf8, (byte) 0);
>     }
> }
>
>  // Output:
> // Exception in thread "main" java.lang.Error: 1346815: 50
> //         at TestBug2.testBug(TestBug2.java:15)
> //                 at TestBug2.main(TestBug2.java:7)
> //
>
>  The above output is on Linux x64
>
>  java -version:
>
>  java version "1.7.0_07"
>  Java(TM) SE Runtime Environment (build 1.7.0_07-b10)
> Java HotSpot(TM) 64-Bit Server VM (build 23.3-b01, mixed mode)
>
>
>  Yes, I know this isn't a list to receive support, etc., I'm just
> surprised at its current priority of low.
>
>  Thanks for your attention,
>
>  Adam
>
>  --
> Adam Hawthorne
> Software Architect
> BASIS International Ltd.
> www.basis.com
> +1.505.938.6169 Phone
> +1.505.750.4128 Direct
>
>


-- 
Adam Hawthorne
Software Architect
BASIS International Ltd.
www.basis.com
+1.505.938.6169 Phone
+1.505.750.4128 Direct
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