<div dir="ltr"><div dir="ltr"><div>lld-link is command-line compatible with MSVC link.exe, so it takes Windows-style linker options. It doesn't take Unix-style linker options. You are also expected to invoke lld-link directly instead of using the compiler driver (i.e. clang or cc) because that's how the linker is supposed to be used on Windows.</div><div><br></div><div>I *believe* you should use clang-cl to create COFF object files and then link them using the following command</div><div><br></div><div>$ lld-link -subsystem:efi_application -nodefaultlib -dll -WX -entry:efi_main -out:yourapp.exe *.obj<br></div><div><br></div><div>but I may be wrong because I've never tested this myself.</div><div><br></div><div>(By the way, what is linux-gnu option?)</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Jan 28, 2019 at 10:03 PM Shi, Steven <<a href="mailto:steven.shi@intel.com">steven.shi@intel.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div lang="EN-US">
<div class="gmail-m_-478052316542733692WordSection1">
<p class="MsoNormal"><a name="m_-478052316542733692__MailEndCompose"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Hi Rui,<u></u><u></u></span></a></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">A quick question: Does lld-link only work with clang-cl with windows-msvc option? Can lld-link work with clang with linux-gnu option?
<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
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<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Thanks<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
<p class="MsoNormal"><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Steven Shi</span></b><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)"><u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Intel\SSG\FID\Firmware Infrastructure</span></b><b><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)"><u></u><u></u></span></b></p>
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<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
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<p class="MsoNormal"><a name="m_-478052316542733692______replyseparator"></a><b><span style="font-size:11pt;font-family:Calibri,sans-serif">From:</span></b><span style="font-size:11pt;font-family:Calibri,sans-serif"> Shi, Steven
<br>
<b>Sent:</b> Tuesday, January 29, 2019 1:32 PM<br>
<b>To:</b> 'Rui Ueyama' <<a href="mailto:ruiu@google.com" target="_blank">ruiu@google.com</a>><br>
<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><br>
<b>Subject:</b> RE: lld write wrong symbol value in .data section if enable -pie<u></u><u></u></span></p>
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<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">></span> It seems to me that it is a great opportunity to simplify build process<span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">I agree and we’re investigating the various options with lld. Uefi build has been existed for ~20 years and support multiple compilers, arches and OSes. If the
lld can really cover all build features and meet Uefi various requirements, I believe we use it as default linker to make build simple.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Thanks<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
<p class="MsoNormal"><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Steven Shi<u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Intel\SSG\FID\Firmware Infrastructure</span></b><b><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)"><u></u><u></u></span></b></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p>
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<p class="MsoNormal"><b><span style="font-size:11pt;font-family:Calibri,sans-serif">From:</span></b><span style="font-size:11pt;font-family:Calibri,sans-serif"> Rui Ueyama [<a href="mailto:ruiu@google.com" target="_blank">mailto:ruiu@google.com</a>]
<br>
<b>Sent:</b> Tuesday, January 29, 2019 1:08 PM<br>
<b>To:</b> Shi, Steven <<a href="mailto:steven.shi@intel.com" target="_blank">steven.shi@intel.com</a>><br>
<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><br>
<b>Subject:</b> Re: lld write wrong symbol value in .data section if enable -pie<u></u><u></u></span></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<p class="MsoNormal">I know nothing about your project, so bear with me if my reply is pointless...<u></u><u></u></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<div>
<p class="MsoNormal">I'm still wondering if just using lld-link is (at least in theory) the best option for you guys. Before lld, I believe creating UEFI applications was tricky; I've heard of a story of creating it by transplanting a ELF text segment to an
empty PE file using objcopy.<u></u><u></u></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<div>
<p class="MsoNormal">But now lld is there. It is always a cross-linker, so however you built lld, it is always capable of creating UEFI applications on any host. Doesn't that mean you could remove all hacks such as converting ELF to COFF, creating PE/COFF executables
using linker scripts, or doing LTO just to not emit certain types of relocations that the existing tools cannot handle, no? It seems to me that it is a great opportunity to simplify build process, but maybe I'm missing something...<u></u><u></u></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<div>
<p class="MsoNormal">On Mon, Jan 28, 2019 at 6:56 PM Shi, Steven <<a href="mailto:steven.shi@intel.com" target="_blank">steven.shi@intel.com</a>> wrote:<u></u><u></u></p>
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<p class="MsoNormal"><a name="m_-478052316542733692_m_-1530537946169652820__MailEndCompose"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Hi Rui,</span></a><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">></span> but why don't you use lld-link (lld for Windows target) instead of ld.lld (lld for Unix target)
to create UEFI applications?<u></u><u></u></p>
<p style="margin:0in 0in 0.0001pt"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">I need support both PE/COFF and ELF format tools. I’m also working on the lld-link enabling (clang-cl + lld-link) in both Linux and windows.
The ld.lld enabling (clang + ld.lld) is for ELF format native users. E.g. </span>
<a href="https://ci.linaro.org/view/leg-ci/job/leg-virt-tianocore-edk2-upstream/configure" target="_blank"><span style="font-size:11pt;font-family:Calibri,sans-serif">https://ci.linaro.org/view/leg-ci/job/leg-virt-tianocore-edk2-upstream/configure</span></a><span style="font-size:11pt;font-family:Calibri,sans-serif;color:black">.
</span><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Uefi firmware have many open source developers who like ELF format toolchains …</span><u></u><u></u></p>
<p style="margin:0in 0in 0.0001pt"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Yes, Uefi firmware application/driver are PE/COFF format. So for ELF format object file, we have a
tool to convert ELF to COFF: </span><a href="https://github.com/tianocore/edk2/tree/master/BaseTools/Source/C/GenFw" target="_blank"><span style="font-size:11pt;font-family:Calibri,sans-serif">https://github.com/tianocore/edk2/tree/master/BaseTools/Source/C/GenFw</span></a><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">.
Our convert tool cannot handle complex relocation types, like GOT based. That’s why we use the symbol hidden visibility, LTO and other options to let gcc/clang not emit complex relocation.</span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Thanks</span><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
<p class="MsoNormal"><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Steven Shi</span></b><u></u><u></u></p>
<p class="MsoNormal"><b><span style="font-size:10pt;font-family:Arial,sans-serif;color:rgb(31,73,125)">Intel\SSG\FID\Firmware Infrastructure</span></b><u></u><u></u></p>
<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"> </span><u></u><u></u></p>
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<p class="MsoNormal"><a name="m_-478052316542733692_m_-1530537946169652820______replyseparat"></a><b><span style="font-size:11pt;font-family:Calibri,sans-serif">From:</span></b><span style="font-size:11pt;font-family:Calibri,sans-serif">
Rui Ueyama [mailto:<a href="mailto:ruiu@google.com" target="_blank">ruiu@google.com</a>]
<br>
<b>Sent:</b> Tuesday, January 29, 2019 12:38 AM<br>
<b>To:</b> Shi, Steven <<a href="mailto:steven.shi@intel.com" target="_blank">steven.shi@intel.com</a>><br>
<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><br>
<b>Subject:</b> Re: lld write wrong symbol value in .data section if enable -pie</span><u></u><u></u></p>
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<p class="MsoNormal"> <u></u><u></u></p>
<div>
<p class="MsoNormal">Hi Steven,<u></u><u></u></p>
<div>
<p class="MsoNormal"> <u></u><u></u></p>
</div>
<div>
<p class="MsoNormal">This is not a direct answer or suggestion for your problem, but why don't you use lld-link (lld for Windows target) instead of ld.lld (lld for Unix target) to create UEFI applications?
A quick google search showed me that UEFI applications are in PE/COFF format, and I can even find people who successfully created UEFI applications using lld-link. Looks like that's much more straightforward way than hacking ld.lld with linker scripts.<u></u><u></u></p>
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<p class="MsoNormal"> <u></u><u></u></p>
<div>
<div>
<p class="MsoNormal">On Mon, Jan 28, 2019 at 7:35 AM Shi, Steven <<a href="mailto:steven.shi@intel.com" target="_blank">steven.shi@intel.com</a>> wrote:<u></u><u></u></p>
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<p class="MsoNormal">Hi Rui,<u></u><u></u></p>
<p class="MsoNormal">I still fail to enable the lld in my Uefi firmware build to replace ld, and I found it is related to the wrong symbol values in the .data section, which are pointed by R_X86_64_64
relocation entries. I need your advices.<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">My firmware uses a linker script
<a href="https://github.com/tianocore/edk2/blob/master/BaseTools/Scripts/GccBase.lds" target="_blank">
https://github.com/tianocore/edk2/blob/master/BaseTools/Scripts/GccBase.lds</a> to do the linking. We use position independent code with hidden visibility to inform the compiler that symbol references are never resolved at runtime. My problem is I found after
the lld linking with –pie enabled, the symbol values in .data section, which have the R_X86_64_64 relocation entries, are all 0. In other word, I found the S in below R_X86_64_64 calculation is 0.<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<table class="gmail-m_-478052316542733692MsoNormalTable" border="0" cellspacing="0" cellpadding="0" style="border-collapse:collapse">
<tbody>
<tr>
<td width="188" style="width:141pt;border:1pt solid windowtext;padding:0in 5.4pt">
<p class="MsoNormal"><span style="font-size:9pt;font-family:NimbusRomNo9L-Regu,serif;color:black">Name:</span>
<span style="font-size:9pt;font-family:NimbusMonL-Regu,serif;color:black">R_X86_64_64
</span><u></u><u></u></p>
</td>
<td width="42" style="width:31.5pt;border-top:1pt solid windowtext;border-right:1pt solid windowtext;border-bottom:1pt solid windowtext;border-left:none;padding:0in 5.4pt">
<p class="MsoNormal"><span style="font-size:9pt;font-family:NimbusRomNo9L-Regu,serif;color:black">1
</span><u></u><u></u></p>
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<td width="67" style="width:50.25pt;border-top:1pt solid windowtext;border-right:1pt solid windowtext;border-bottom:1pt solid windowtext;border-left:none;padding:0in 5.4pt">
<p class="MsoNormal"><i><span style="font-size:9pt;font-family:NimbusRomNo9L-ReguItal,serif;color:black">word64
</span></i><u></u><u></u></p>
</td>
<td width="150" style="width:112.5pt;border-top:1pt solid windowtext;border-right:1pt solid windowtext;border-bottom:1pt solid windowtext;border-left:none;padding:0in 5.4pt">
<p class="MsoNormal"><span style="font-size:9pt;font-family:NimbusMonL-Regu,serif;color:black">S + A</span><u></u><u></u></p>
</td>
</tr>
</tbody>
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<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">Below is an example to compare the lld and ld, sorry about the verbose.<u></u><u></u></p>
<p class="gmail-m_-478052316542733692gmail-m-1530537946169652820gmail-m7943837711040915951msolistparagraph">
1.<span style="font-size:7pt"> </span>Firstly, I use lld to link a HelloWorld module with -pie enabled:<u></u><u></u></p>
<p class="MsoNormal">"/home/jshi19/llvm/releaseinstall/bin/<span style="color:red">ld.lld</span>"
<span style="color:red">-pie </span>-z relro --hash-style=gnu --eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib64/ld-linux-x86-64.so.2 -o /home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/DEBUG/HelloWorld.dll
-u _ModuleEntryPoint -L/usr/lib/gcc/x86_64-linux-gnu/7.3.0 -L/usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../x86_64-linux-gnu -L/lib/x86_64-linux-gnu -L/lib/../lib64 -L/usr/lib/x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../.. -L/home/jshi19/llvm/releaseinstall/bin/../lib
-L/lib -L/usr/lib -q --gc-sections -z max-page-size=0x40 --entry _ModuleEntryPoint -Map /home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/DEBUG/HelloWorld.map --whole-archive -O0 -melf_x86_64 --oformat
elf64-x86-64 --start-group @/home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/OUTPUT/static_library_files.lst --end-group --defsym=PECOFF_HEADER_SIZE=0x228 --script=/home/jshi19/wksp_efi/lgao4/edk2/BaseTools/Scripts/GccBase.lds<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="gmail-m_-478052316542733692gmail-m-1530537946169652820gmail-m7943837711040915951msolistparagraph">
2.<span style="font-size:7pt"> </span>Then, I check the R_X86_64_64 relocation entries in .rela.data section, and find their target offsets<u></u><u></u></p>
<p class="MsoNormal">$ readelf -r /home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/DEBUG/HelloWorld.dll<u></u><u></u></p>
<p class="MsoNormal">Relocation section '.rela.data' at offset 0x5b7e8 contains 41 entries:<u></u><u></u></p>
<p class="MsoNormal"> Offset Info Type Sym. Value Sym. Name + Addend<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal"><span style="color:red">000000005040
</span>00d600000001 R_X86_64_64 0000000000003130 TestFunction1 + 0<u></u><u></u></p>
<p class="MsoNormal"><span style="color:red">000000005048
</span>00d700000001 R_X86_64_64 0000000000003150 TestFunction2 + 0<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="gmail-m_-478052316542733692gmail-m-1530537946169652820gmail-m7943837711040915951msolistparagraph">
3.<span style="font-size:7pt"> </span>Next, I check the symbol values in .data section which are targeted by above R_X86_64_64 relocatons<u></u><u></u></p>
<p class="MsoNormal">$ readelf -x2 HelloWorld.dll <u></u><u></u></p>
<p class="MsoNormal">Hex dump of section '.data':<u></u><u></u></p>
<p class="MsoNormal">NOTE: This section has relocations against it, but these have NOT been applied to this dump.<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal"> 0x00005030 00000000 00000000 00000000 00000000 ................<u></u><u></u></p>
<p class="MsoNormal">
<span style="color:red">0x00005040 00000000 00000000 00000000 00000000 </span>................<u></u><u></u></p>
<p class="MsoNormal"> 0x00005050 4ebe7903 06d77d43 b037edb8 2fb772a4 N.y...}C.7../.r.<u></u><u></u></p>
<p class="MsoNormal"> 0x00005060 00000000 00000000 00000000 00000000 ................<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal">You can see the offset 0x5040 and 0x5048 symbol value are all 0, which is not correct.<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">But if I remove the -pie option in the above step 1 lld link command, the 0x5040 and 0x5048 symbol values are correct.<u></u><u></u></p>
<p class="MsoNormal">$ readelf -x2 HelloWorld.dll <u></u><u></u></p>
<p class="MsoNormal">Hex dump of section '.data':<u></u><u></u></p>
<p class="MsoNormal">NOTE: This section has relocations against it, but these have NOT been applied to this dump.<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal"> 0x00005030 04420000 00000000 00000000 00000000 .B..............<u></u><u></u></p>
<p class="MsoNormal"><span style="color:red"> 0x00005040 30310000 00000000 50310000 00000000 01......P1......</span><u></u><u></u></p>
<p class="MsoNormal"> 0x00005050 4ebe7903 06d77d43 b037edb8 2fb772a4 N.y...}C.7../.r.<u></u><u></u></p>
<p class="MsoNormal"> 0x00005060 00000000 00000000 00000000 00000000 ................<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">And if I replace lld with ld but still use exact same link options with –pie enabled, the R_X86_64_64 symbol values are correct.<u></u><u></u></p>
<p class="gmail-m_-478052316542733692gmail-m-1530537946169652820gmail-m7943837711040915951msolistparagraph">
1.<span style="font-size:7pt"> </span>Link again with ld and same link options:<u></u><u></u></p>
<p class="MsoNormal"><span style="color:red">ld -pie
</span>-z relro --hash-style=gnu --eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib64/ld-linux-x86-64.so.2 -o /home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/DEBUG/HelloWorld.dll -u _ModuleEntryPoint
-L/usr/lib/gcc/x86_64-linux-gnu/7.3.0 -L/usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../x86_64-linux-gnu -L/lib/x86_64-linux-gnu -L/lib/../lib64 -L/usr/lib/x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../.. -L/home/jshi19/llvm/releaseinstall/bin/../lib
-L/lib -L/usr/lib -q --gc-sections -z max-page-size=0x40 --entry _ModuleEntryPoint -Map /home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/DEBUG/HelloWorld.map --whole-archive -O0 -melf_x86_64 --oformat
elf64-x86-64 --start-group @/home/jshi19/wksp_efi/lgao4/edk2/Build/OvmfX64/NOOPT_CLANG38/X64/MdeModulePkg/Application/HelloWorld/HelloWorld/OUTPUT/static_library_files.lst --end-group --defsym=PECOFF_HEADER_SIZE=0x228 --script=/home/jshi19/wksp_efi/lgao4/edk2/BaseTools/Scripts/GccBase.lds<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="gmail-m_-478052316542733692gmail-m-1530537946169652820gmail-m7943837711040915951msolistparagraph">
2.<span style="font-size:7pt"> </span>Then, check the .rela.data section R_X86_64_64 relocation entries:<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal"><span style="color:red">000000004f40
</span>00a400000001 R_X86_64_64 0000000000003130 TestFunction1 + 0<u></u><u></u></p>
<p class="MsoNormal"><span style="color:red">000000004f48
</span>009a00000001 R_X86_64_64 0000000000003150 TestFunction2 + 0<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="gmail-m_-478052316542733692gmail-m-1530537946169652820gmail-m7943837711040915951msolistparagraph">
3.<span style="font-size:7pt"> </span>Check the R_X86_64_64 targeting symbol values in .data section<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal"> 0x00004f30 f3410000 00000000 00000000 00000000 .A..............<u></u><u></u></p>
<p class="MsoNormal">
<span style="color:red">0x00004f40 30310000 00000000 50310000 00000000 01......P1......</span><u></u><u></u></p>
<p class="MsoNormal"> 0x00004f50 00000000 00000000 00000000 00000000 ................<u></u><u></u></p>
<p class="MsoNormal">… …<u></u><u></u></p>
<p class="MsoNormal">You can see the offset 0x4f40 and 0x4f48 symbol value are not 0, which is correct.<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">Appreciate if you could give me some advices on how to let lld output correct symbol values when enable pie.<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">Thanks<u></u><u></u></p>
<p class="MsoNormal">Steven<u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p>
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