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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black">Hi, Kim and Openjdk8-dev,</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">One of our internal service crashes in G1 Full GC. The error message is very similar to <a href="https://bugs.openjdk.java.net/browse/JDK-8177900"><span style="color:#954F72">JDK-8177900</span></a>. Because
our service intensively uses MethodHandle to generate MemberName objects. In Openjdk8u, methodHandles.cpp also generates jweak for resolved MemberName. Does it also need to generate pre-barrier? Otherwise, I think it has race-condition for ConcurrentGC.<br>
<br>
</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">I observed a newly-allocated DirectMethodHandle object points to a dead MemberName object in G1 remark phase. I backported the patch associated with <a href="https://bugs.openjdk.java.net/browse/JDK-8176100"><span style="color:#954F72">JDK-8176100</span></a> to
x86-64. It works. I wonder if it’s necessary to backport the patch to jdk8u. if not, how can openjdk8u avoid the race condition?</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">Another question is which regression test can trigger the issue? Why did you only identify the problem on jdk9+?</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">Thanks,</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">--lx</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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