double free or corruption

[Deneau, Tom]

I tried valgrind on a fairly simple mx unittest run for which the list of unittests was basically 32 copies of com.oracle.graal.jtt.bytecode.BC_aload_1
com.oracle.graal.jtt.bytecode.BC_aload_0
com.oracle.graal.jtt.bytecode.BC_aload_3
com.oracle.graal.jtt.bytecode.BC_aload_2

I get some valgrind errors of the following form.   Is this expected?
I seem to only see this on the product build, not fastdebug or debug.

==11432==  Address 0x206c0ed8 is 8 bytes inside a block of size 24 free'd
==11432==    at 0x4C2B60C: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==11432==    by 0x61E5810: InlineCacheBuffer::update_inline_caches() (allocation.inline.hpp:83)
==11432==    by 0x64EFF9F: SafepointSynchronize::do_cleanup_tasks() (safepoint.cpp:527)
==11432==    by 0x64F0914: SafepointSynchronize::begin() (safepoint.cpp:403)
==11432==    by 0x65FCFB9: VMThread::loop() (vmThread.cpp:496)
==11432==    by 0x65FD411: VMThread::run() (vmThread.cpp:274)
==11432==    by 0x6459EC1: java_start(Thread*) (os_linux.cpp:860)


-- Tom


-----Original Message-----
From: graal-dev [mailto:graal-dev-bounces at openjdk.java.net] On Behalf Of Deneau, Tom
Sent: Tuesday, July 22, 2014 11:33 AM
To: graal-dev at openjdk.java.net
Subject: double free or corruption

What is the best technique to debug an error like the following (after having made some hotspot changes)...

-- Tom

*** Error in `/home/user1/SumatraDemos/graal/jdk1.8.0-internal/product/bin/java': double free or corruption (!prev): 0x00002b80e8517a30 ***