[PATCH] Link to the Sun JVM bug mentioned in OffsetCache

This bug has now been published by Sun.  We should link to the
database entry so we can find more detail later.

Signed-off-by: Shawn O. Pearce <redacted>
---
  "Shawn O. Pearce" [off-list ref] wrote:
  > Robin Rosenberg [off-list ref] wrote:
  > > > diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/OffsetCache.java b/org.spearce.jgit/src/org/spearce/jgit/lib/OffsetCache.java
  > > > +	private void gc() {
  > > > +		R r;
  > > > +		while ((r = (R) queue.poll()) != null) {
  > > > +			// Sun's Java 5 and 6 implementation have a bug where a Reference
  > > > +			// can be enqueued and dequeued twice on the same reference queue
  > > > +			// due to a race condition within ReferenceQueue.enqueue(Reference).
  > > 
  > > Reference to the official Sun bug? Might help if someone wants to
  > > implement a flag to avoid this (if necessary...)
  > 
  > Actually, this is a new bug.  I tried looking through BugParade
  > but nobody has mentioned or discovered this before.
  > 
  > I submitted a bug report yesterday, but they have yet to publish it.

  And here it is.

 .../src/org/spearce/jgit/lib/OffsetCache.java      |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/OffsetCache.java b/org.spearce.jgit/src/org/spearce/jgit/lib/OffsetCache.java
index a1cd4be..b81c7e0 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/OffsetCache.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/OffsetCache.java

@@ -414,6 +414,8 @@ private void gc() {
 			// can be enqueued and dequeued twice on the same reference queue
 			// due to a race condition within ReferenceQueue.enqueue(Reference).
 			//
+			// http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6837858
+			//
 			// We CANNOT permit a Reference to come through us twice, as it will
 			// skew the resource counters we maintain. Our canClear() check here
 			// provides a way to skip the redundant dequeues, if any.

-- 
1.6.3.rc4.206.g03e16