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<p class="MsoNormal"><span lang="EN-IN">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-IN"><o:p> </o:p></span></p>
<p class="MsoNormal">We wanted to experiment as to how we can use the BOLT optimization from LLVM on our Android Platforms.<o:p></o:p></p>
<p class="MsoNormal">We referred to the wiki from Facebook that speaks of Bolt <span lang="EN-IN">
<o:p></o:p></span></p>
<p class="MsoNormal"><a href="https://github.com/facebookincubator/BOLT" target="_blank">https://github.com/facebookincubator/BOLT</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So I was using now the linker flag : "Wl,--emit-relocs" in the instrumented mode to compile android module , for instance here “libc”.<o:p></o:p></p>
<p class="MsoNormal">But the build fails with the llvm clang toolchain on android :<o:p></o:p></p>
<p class="MsoNormal">============================<o:p></o:p></p>
<p class="MsoNormal">FAILED: out/soong/.intermediates/bionic/libc/libc/android_x86_core_shared/libc.so prebuilts/clang/host/linux-x86/clang-4691093/bin/clang++ <o:p></o:p></p>
<p class="MsoNormal">.....<o:p></o:p></p>
<p class="MsoNormal">.....<o:p></o:p></p>
<p class="MsoNormal">-Wl,--no-undefined -Wl,--hash-style=gnu <b>-Wl,--emit-relocs</b> -Wl,--hash-style=both -m32 -Wl,--version-script,bionic/libc/libc.x86.map <o:p></o:p></p>
<p class="MsoNormal">prebuilts/gcc/linux-x86/x86/x86_64-linux-android-4.9/x86_64-linux-android/bin/ld:<b> internal error in do_layout, at</b> /buildbot/src/android/gcc/toolchain/build/../binutils/binutils-2.27/gold/<b>object.cc:1821 </b>
<o:p></o:p></p>
<p class="MsoNormal">clang-6.0: error: linker command failed with exit code 1 (use -v to see invocation) <o:p></o:p></p>
<p class="MsoNormal">==============================<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am using android clang prebuilts : "clang-4691093". Does the clang based llvm compiler need any special changes to use this compiler relocation compiler flag?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best Regards<o:p></o:p></p>
<p class="MsoNormal">Priyanka<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-IN"><o:p> </o:p></span></p>
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