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<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Hi Tyler, we had the flags -</span><span style="font-size:12.0pt;color:black">qnoeh and -qno</span><span lang="EN-US" style="font-size:12.0pt;color:black">r</span><span style="font-size:12.0pt;color:black">tti</span><span lang="EN-US" style="font-size:12.0pt;color:black">
already set before 2010 in our internal AIX build (some time before the AIX OpenJDK port started).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;color:black">Probably the features were not needed in those ancient times .<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;color:black">I took over the flags when doing the xlc16 support changes in OpenJDK .<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:12.0pt;color:black">Best regards, Matthias<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> ppc-aix-port-dev <ppc-aix-port-dev-retn@openjdk.org>
<b>On Behalf Of </b>Tyler Steele<br>
<b>Sent:</b> Wednesday, 21 June 2023 20:31<br>
<b>To:</b> ppc-aix-port-dev@openjdk.org<br>
<b>Subject:</b> The History of nortti and noeh on AIX<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Hi all,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">I was recently asked [1] why we include -qnoeh [2] and -qnoftti [3] with the build. It looks like it's been in the project since at least jdk9 [4], but I suspect that might not be the true origin
of the flags.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Reading the descriptions for the flags makes me suspect that these were added to improve performance "For improved runtime performance, suppress RTTI information generation with the
<span class="keyword">-qnortti</span> setting." [2] and possibly to reduce code bloat "If your program does not use C++ structured exception handling, you can compile with
<span class="keyword">-qnoeh</span> to prevent generation of code that is not needed by your application." [3]. But these are just guesses. Any chance that anyone out there knows/remembers why these were added?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Tyler<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">[1] <a href="https://github.com/adoptium/adoptium-support/issues/824#issuecomment-1599049333">
https://github.com/adoptium/adoptium-support/issues/824#issuecomment-1599049333</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">[2] <a href="https://www.ibm.com/docs/en/xl-c-and-cpp-aix/16.1?topic=descriptions-qrtti-qnortti-fno-rtti-c-only">
https://www.ibm.com/docs/en/xl-c-and-cpp-aix/16.1?topic=descriptions-qrtti-qnortti-fno-rtti-c-only</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">[3] <a href="https://www.ibm.com/docs/en/xl-c-and-cpp-aix/16.1?topic=descriptions-qeh-fexceptions-c-only#opt_eh">
https://www.ibm.com/docs/en/xl-c-and-cpp-aix/16.1?topic=descriptions-qeh-fexceptions-c-only#opt_eh</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">[4] <a href="https://github.com/openjdk/jdk/commit/e709aa268df64b2dc000433a1d9621a2fb0940f0">
https://github.com/openjdk/jdk/commit/e709aa268df64b2dc000433a1d9621a2fb0940f0</a><o:p></o:p></span></p>
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