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<p class="MsoNormal"><a name="_MailEndCompose">>Steven,<o:p></o:p></a></p>
<p class="MsoNormal">>Do you need to use LTO? I thought that LTO is a workaround to not produce an object file that cannot be handled by your ELF-to-COFF translation tool. If you are now doing a regular cross build, I guess you can remove -flto.<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Yes, I need the LTO for the smallest code size. Without LTO, my firmware image will be +30% larger which is not competitive with MSVC.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Steven
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><a name="_____replyseparator"></a><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Rui Ueyama [mailto:ruiu@google.com]
<br>
<b>Sent:</b> Thursday, February 28, 2019 8:01 AM<br>
<b>To:</b> Shi, Steven <steven.shi@intel.com>; Peter Collingbourne <pcc@chromium.org><br>
<b>Cc:</b> Peter Smith <peter.smith@linaro.org>; Martin Storsjö <martin@martin.st>; llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Re: lld-link crash when linking intrinsics lib<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><a href="mailto:pcc@chromium.org" target="_blank">+Peter Collingbourne</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">LTO is used in this test case, and one source file defines its own `memset` function while the other file uses llvm.memset. Looks like LTO is confused by the user-defined memset. Could you take a look?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Steven,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Do you need to use LTO? I thought that LTO is a workaround to not produce an object file that cannot be handled by your ELF-to-COFF translation tool. If you are now doing a regular cross build, I guess you can remove -flto.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Feb 27, 2019 at 3:00 PM Rui Ueyama <<a href="mailto:ruiu@google.com" target="_blank">ruiu@google.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Hi Steven,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I confirmed that lld-link crashes with these inputs. That shouldn't happen. I'll debug this and get back to you. Thank you for reporting.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Tue, Feb 26, 2019 at 8:20 PM Shi, Steven <<a href="mailto:steven.shi@intel.com" target="_blank">steven.shi@intel.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hello Rui,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I met couples of lld-link crash when enable the clang-cl + lld-link build toolchain for Uefi firmware. Below is a simplified example (main.c and intrinsics.c).
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Uefi firmware is self-contained and doesn’t depend on the compiler intrinsics implementation, so we have our own intrinsics lib. It is weird that if I don’t use the llvm-lib but
directly “lld-link /NODEFAULTLIB /ENTRY:main main.obj intrinsics.obj”, the below example can pass link. Please advise what’s wrong in this example.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ cat main.c<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">typedef struct {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> struct MAP_LIST {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> unsigned long long VirtualAddress;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> void *MapCookie;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> } MapList[100];<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">} SNP_DRIVER;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">SNP_DRIVER snp_instance;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">int main()<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">{<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> SNP_DRIVER *Snp;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> Snp = &snp_instance;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> for (int Index = 0; Index < 100; Index++) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> Snp->MapList[Index].VirtualAddress = 0;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> Snp->MapList[Index].MapCookie = 0;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> }<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> return 0;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">}<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ cat intrinsics.c<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">void * memset (void *dest, int ch, size_t count)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">{<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> volatile char *Pointer;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> Pointer = (char *)dest;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> while (count-- != 0) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> *(Pointer++) = (char)ch;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> }<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> return dest;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">}<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ "/home/jshi19/llvm/releaseinstall/bin/clang-cl" /Fomain.obj /c --target=x86_64-pc-win32-coff -m64 /O1b2s -flto main.c<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ "/home/jshi19/llvm/releaseinstall/bin/clang-cl" /Fointrinsics.obj /c --target=x86_64-pc-win32-coff -m64 /O1b2s -flto intrinsics.c<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ "/home/jshi19/llvm/releaseinstall/bin/llvm-lib" /OUT:intrinsics.lib intrinsics.obj<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ "/home/jshi19/llvm/releaseinstall/bin/lld-link" /NODEFAULTLIB /ENTRY:main main.obj intrinsics.lib<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Stack dump:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">0. Program arguments: /home/jshi19/llvm/releaseinstall/bin/lld-link /NODEFAULTLIB /ENTRY:main main.obj intrinsics.lib<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#0 0x0000559a34ba5e4a llvm::sys::PrintStackTrace(llvm::raw_ostream&) (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x272e4a)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#1 0x0000559a34ba3d14 llvm::sys::RunSignalHandlers() (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x270d14)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#2 0x0000559a34ba3e52 SignalHandler(int) (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x270e52)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#3 0x00007f896c8ea890 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12890)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#4 0x0000559a34c11325 lld::coff::markLive(llvm::ArrayRef<lld::coff::Chunk*>) (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x2de325)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#5 0x0000559a34bf0220 lld::coff::LinkerDriver::link(llvm::ArrayRef<char const*>) (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x2bd220)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#6 0x0000559a34bf0478 lld::coff::link(llvm::ArrayRef<char const*>, bool, llvm::raw_ostream&) (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x2bd478)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#7 0x0000559a34b2a300 main (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x1f7300)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#8 0x00007f896b3c1b97 __libc_start_main /build/glibc-OTsEL5/glibc-2.27/csu/../csu/libc-start.c:344:0<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">#9 0x0000559a34b8c27a _start (/home/jshi19/llvm/releaseinstall/bin/lld-link+0x25927a)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Segmentation fault (core dumped)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ "/home/jshi19/llvm/releaseinstall/bin/clang-cl" --version<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">clang version 9.0.0 (<a href="https://github.com/llvm-mirror/clang.git" target="_blank">https://github.com/llvm-mirror/clang.git</a> 1f02068469ff18f5fc5728cafe9d96ee5f66c5b9) (<a href="https://github.com/llvm-project/llvm.git" target="_blank">https://github.com/llvm-project/llvm.git</a>
330395ea4fce35b019b33797ff751be029a1f866)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Target: x86_64-pc-windows-msvc<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thread model: posix<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">InstalledDir: /home/jshi19/llvm/releaseinstall/bin<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">$ "/home/jshi19/llvm/releaseinstall/bin/lld-link" --version<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">LLD 9.0.0 (<a href="https://github.com/llvm-mirror/lld.git" target="_blank">https://github.com/llvm-mirror/lld.git</a> aa7adc0ec804b689771f11d52e39f83a16378f5f)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Steven Shi</span></b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Intel\SSG\FID\Firmware Infrastructure</span></b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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