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<p class="MsoNormal"><span lang="EN-US">Hi, Memory sanitizer<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="https://clang.llvm.org/docs/MemorySanitizer.html">https://clang.llvm.org/docs/MemorySanitizer.html</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">is supported with the clang toolchain (e.g. on Linux) ; “</span><span lang="en-DE">MemorySanitizer is a detector of uninitialized memory use</span><span lang="EN-US">” .<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">For small examples it is rather easy to use, you just compile and link with
</span>-fsanitize=memory (and for better results maybe additionally -fno-omit-frame-pointer ) .<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So I gave it a try with OpenJDK too and added -fsanitize=memory to the C/CXX and LD flags (--with-extra-cflags=-fsanitize=memory --with-extra-cxxflags=-fsanitize=memory --with-extra-ldflags=-fsanitize=memory ).<o:p></o:p></p>
<p class="MsoNormal">As far as compiling single compilation units this seems to be okay .<o:p></o:p></p>
<p class="MsoNormal">But when it comes to executing the new generated binaries in the build process we unfortunately get lookup errors / undefined symbols :<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">/builddir/jdk/bin/javac: symbol lookup error: /builddir/jdk/bin/../lib/libjli.so: undefined symbol: __msan_param_tls<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there something special in our OpenJDK build that causes trouble here ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here I found an somewhat similar looking issue :<o:p></o:p></p>
<p class="MsoNormal"><a href="https://groups.google.com/g/memory-sanitizer/c/xV3OZZCiL9A">https://groups.google.com/g/memory-sanitizer/c/xV3OZZCiL9A</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">where re-exporting symbols is mentioned - is this maybe something that hits us in OpenJDK too ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For address sanitizer, we set -shared-libasan in the OpenJDK :
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="https://github.com/openjdk/jdk/blob/5c067232bf21aaca2b7addd2a862e15a8696ffb8/make/autoconf/jdk-options.m4#L449">https://github.com/openjdk/jdk/blob/5c067232bf21aaca2b7addd2a862e15a8696ffb8/make/autoconf/jdk-options.m4#L449</a><o:p></o:p></p>
<p class="MsoNormal">ASAN_LDFLAGS="$ASAN_LDFLAGS -shared-libasan"<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">But I could not find something similar for msan .<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(btw. I use clang 15.0.7 on SUSE Linux x86_64 in case this matters)
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards, Matthias<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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