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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I’d like to propose a fix for an old issue on 32 bit Windows (also for an 11u backport):<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="https://bugs.openjdk.java.net/browse/JDK-8220348">https://bugs.openjdk.java.net/browse/JDK-8220348</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Some jdk native methods use jni_SetLongArrayRegion with a stack allocated buffer.
<br>
jni_SetLongArrayRegion uses Copy::conjoint_jlongs_atomic which requires jlongs to be 8 byte aligned (asserted).
<br>
However, Windows 32 bit only uses 4 byte alignment for jlong arrays by default. <br>
I found such issues in the following files: <br>
src/java.prefs/windows/native/libprefs/WindowsPreferences.c <br>
src/java.security.jgss/share/native/libj2gss/GSSLibStub.c <br>
I suggest to use __declspec(align(8)) there.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Webrev:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="http://cr.openjdk.java.net/~mdoerr/8220348_ntintel_stack_align/webrev.00/">http://cr.openjdk.java.net/~mdoerr/8220348_ntintel_stack_align/webrev.00/</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Please review.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I think using 8 byte alignment is not a disadvantage for 64 bit.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I guess there are still people interested in this platform with jdk14. Otherwise I could contribute it as 11u only fix.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Is there a better way to force 8 byte alignment for jlongs or jlong arrays on stack?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Martin<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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