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<p>Hello Chen,</p>
<p>Looking at the implementation of java.lang.Class.getName(), which
then triggers the hotspot code to initialize this "name" field, I
suspect there will be a (harmless) race in the hotspot
implementation where more than one thread could end up writing the
"name" field (with the same value of course)
<a class="moz-txt-link-freetext" href="https://github.com/openjdk/jdk/blob/master/src/hotspot/share/classfile/javaClasses.cpp#L1237">https://github.com/openjdk/jdk/blob/master/src/hotspot/share/classfile/javaClasses.cpp#L1237</a>.
I don't know how the JVM would then react if such a field is
marked @Stable (the javadoc of @Stable states that the behaviour
is such cases is undefined).<br>
</p>
<p>-Jaikiran<br>
</p>
On 16/12/23 8:37 pm, - wrote:<br>
<blockquote type="cite"
cite="mid:CABe8uE0+5Te8yvZgUrkHn3miY9QF6Z_Cv6=O-+HQ_78SM8C1ww@mail.gmail.com">
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<div dir="ltr">Hello,
<div>I just noticed the Class.name field is mutable but not
@Stable, meaning `Class.getName()` calls are not eligible for
constant folding.</div>
<div><br>
</div>
<div>The last update to this field is in 2019 in JDK-8216302
when the field initialization was done directly by a write
from hotspot code (for the class name is interned anyways,
though interning limits scalability of hidden classes)</div>
<div><br>
</div>
<div>Would it be a good idea to submit a patch to mark this
field @Stable? Given class names may be frequently used to
quickly identify a class, to create descriptors.</div>
<div><br>
</div>
<div>Chen Liang<br>
<a class="gmail_plusreply" moz-do-not-send="true"><br>
</a></div>
</div>
</blockquote>
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