[7u40] Request for phase 2 approval for CR 8017478: Kitchensink crashed with SIGSEGV in BaselineReporter::diff_callsites

[Zhengyu Gu]

JBS: https://jbs.oracle.com/bugs/browse/JDK-8017478 (public bug is not 
available)
Public review: http://cr.openjdk.java.net/~zgu/8017478/webrev.00/ 
<http://cr.openjdk.java.net/%7Ezgu/8017478/webrev.00/>
The change has been committed to jdk8

The change has been reviewed by: Karen Kinnear, Coleen Phillimore and 
Christian Tornqvist

The bug can result crash when executing native memory tracking query, 
and it prevents kitchensink test to reach release criteria. The risk of 
the fix is low, as it basically adds additional checks for null pointer.

I ran the kitchensink test on Solaris 11 Sparcv9.


Thanks,

-Zhengyu