COFF: Emit a COFF symbol table if /debug:dwarf is specified.

[pcc]

Summary

This effectively reverts r318548 and r318635 while keeping the
functionality behind the flag and preserving the bug fix from r318548.

[rnk]

My hope was that we wouldn't need a flag. We'd just figure out if there were long section names that were marked to not be loaded at runtime (i.e. things that look like DWARF) and if so emit the long section table. Or, does DWARF need the full symbol table too?

[pcc]

In D40264#930759, @rnk wrote:

We'd just figure out if there were long section names that were marked to not be loaded at runtime (i.e. things that look like DWARF) and if so emit the long section table.

Right, that is what r318548 did (and what this patch continues to do).

Or, does DWARF need the full symbol table too?

Apparently yes, see Shoaib's reply to r318548 on llvm-commits. On IRC he also mentioned that ld.bfd emits the symbol table like we used to.

[rnk]

Got it, just checking my understanding.

[smeenai]

Thank you! Looks good to me, though I'll let @ruiu or @rnk approve.

[rnk]

lgtm

lld/COFF/Config.h

struct Configuration {
   bool NoEntry = false;
   std::string OutputFile;
   std::string ImportName;
   bool DoGC = true;
   bool DoICF = true;
   bool Relocatable = true;
   bool Force = false;
   bool Debug = false;
+  bool DebugDwarf = false;
   unsigned DebugTypes = static_cast<unsigned>(DebugType::None);
   llvm::SmallString<128> PDBPath;
   std::vector<llvm::StringRef> Argv;
 
   // Symbols in this set are considered as live by the garbage collector.
   std::vector<Symbol *> GCRoot;
 
   std::set<StringRef> NoDefaultLibs;

lld/COFF/Driver.cpp

void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
   }
 
   // Handle miscellaneous boolean flags.
   Config->AllowBind = Args.hasFlag(OPT_allowbind, OPT_allowbind_no, true);
   Config->AllowIsolation =
       Args.hasFlag(OPT_allowisolation, OPT_allowisolation_no, true);
   Config->NxCompat = Args.hasFlag(OPT_nxcompat, OPT_nxcompat_no, true);
   Config->TerminalServerAware = Args.hasFlag(OPT_tsaware, OPT_tsaware_no, true);
+  Config->DebugDwarf = Args.hasArg(OPT_debug_dwarf);
 
   Config->MapFile = getMapFile(Args);
 
   if (errorCount())
     return;
 
   bool WholeArchiveFlag = Args.hasArg(OPT_wholearchive_flag);
   // Create a list of input files. Files can be given as arguments

lld/COFF/Symbols.h

public:
   // Indicates that this symbol will be included in the final image. Only valid
   // after calling markLive.
   bool isLive() const;
 
 protected:
   friend SymbolTable;
   explicit Symbol(Kind K, StringRef N = "")
       : SymbolKind(K), IsExternal(true), IsCOMDAT(false),
-        PendingArchiveLoad(false), IsGCRoot(false), Name(N) {}
+        WrittenToSymtab(false), PendingArchiveLoad(false), IsGCRoot(false),
+        Name(N) {}
 
   const unsigned SymbolKind : 8;
   unsigned IsExternal : 1;
 
   // This bit is used by the \c DefinedRegular subclass.
   unsigned IsCOMDAT : 1;
 
 public:
+  // This bit is used by Writer::createSymbolAndStringTable() to prevent
+  // symbols from being written to the symbol table more than once.
+  unsigned WrittenToSymtab : 1;
+
   // True if this symbol was referenced by a regular (non-bitcode) object.
   unsigned IsUsedInRegularObj : 1;
 
   // True if we've seen both a lazy and an undefined symbol with this symbol
   // name, which means that we have enqueued an archive member load and should
   // not load any more archive members to resolve the same symbol.
   unsigned PendingArchiveLoad : 1;
 

lld/COFF/Writer.cpp

 
 private:
   void createSections();
   void createMiscChunks();
   void createImportTables();
   void createExportTable();
   void assignAddresses();
   void removeEmptySections();
-  void createStringTable();
+  void createSymbolAndStringTable();
   void openFile(StringRef OutputPath);
   template <typename PEHeaderTy> void writeHeader();
   void createSEHTable(OutputSection *RData);
   void setSectionPermissions();
   void writeSections();
   void writeBuildId();
   void sortExceptionTable();
 
+  llvm::Optional<coff_symbol16> createSymbol(Defined *D);
+  size_t addEntryToStringTable(StringRef Str);
+
   OutputSection *findSection(StringRef Name);
   OutputSection *createSection(StringRef Name);
   void addBaserels(OutputSection *Dest);
   void addBaserelBlocks(OutputSection *Dest, std::vector<Baserel> &V);
 
   uint32_t getSizeOfInitializedData();
   std::map<StringRef, std::vector<DefinedImportData *>> binImports();
 
   std::unique_ptr<FileOutputBuffer> &Buffer;
   std::vector<OutputSection *> OutputSections;
   std::vector<char> Strtab;
   std::vector<llvm::object::coff_symbol16> OutputSymtab;
   IdataContents Idata;
   DelayLoadContents DelayIdata;
   EdataContents Edata;
   SEHTableChunk *SEHTable = nullptr;
 
   Chunk *DebugDirectory = nullptr;
   std::vector<Chunk *> DebugRecords;
   CVDebugRecordChunk *BuildId = nullptr;
   Optional<codeview::DebugInfo> PreviousBuildId;
   ArrayRef<uint8_t> SectionTable;
 
   uint64_t FileSize;
-  uint32_t PointerToStringTable = 0;
+  uint32_t PointerToSymbolTable = 0;
   uint64_t SizeOfImage;
   uint64_t SizeOfHeaders;
 };
 } // anonymous namespace
 
 namespace lld {
 namespace coff {
 
void Writer::run() {
   createMiscChunks();
   createImportTables();
   createExportTable();
   if (Config->Relocatable)
     createSection(".reloc");
   assignAddresses();
   removeEmptySections();
   setSectionPermissions();
-  createStringTable();
+  createSymbolAndStringTable();
 
   // We must do this before opening the output file, as it depends on being able
   // to read the contents of the existing output file.
   PreviousBuildId = loadExistingBuildId(Config->OutputFile);
   openFile(Config->OutputFile);
   if (Config->is64()) {
     writeHeader<pe32plus_header>();
   } else {
void Writer::removeEmptySections() {
   OutputSections.erase(
       std::remove_if(OutputSections.begin(), OutputSections.end(), IsEmpty),
       OutputSections.end());
   uint32_t Idx = 1;
   for (OutputSection *Sec : OutputSections)
     Sec->SectionIndex = Idx++;
 }
 
-void Writer::createStringTable() {
+size_t Writer::addEntryToStringTable(StringRef Str) {
+  assert(Str.size() > COFF::NameSize);
+  size_t OffsetOfEntry = Strtab.size() + 4; // +4 for the size field
+  Strtab.insert(Strtab.end(), Str.begin(), Str.end());
+  Strtab.push_back('\0');
+  return OffsetOfEntry;
+}
+
+Optional<coff_symbol16> Writer::createSymbol(Defined *Def) {
+  // Relative symbols are unrepresentable in a COFF symbol table.
+  if (isa<DefinedSynthetic>(Def))
+    return None;
+
+  // Don't write dead symbols or symbols in codeview sections to the symbol
+  // table.
+  if (!Def->isLive())
+    return None;
+  if (auto *D = dyn_cast<DefinedRegular>(Def))
+    if (D->getChunk()->isCodeView())
+      return None;
+
+  coff_symbol16 Sym;
+  StringRef Name = Def->getName();
+  if (Name.size() > COFF::NameSize) {
+    Sym.Name.Offset.Zeroes = 0;
+    Sym.Name.Offset.Offset = addEntryToStringTable(Name);
+  } else {
+    memset(Sym.Name.ShortName, 0, COFF::NameSize);
+    memcpy(Sym.Name.ShortName, Name.data(), Name.size());
+  }
+
+  if (auto *D = dyn_cast<DefinedCOFF>(Def)) {
+    COFFSymbolRef Ref = D->getCOFFSymbol();
+    Sym.Type = Ref.getType();
+    Sym.StorageClass = Ref.getStorageClass();
+  } else {
+    Sym.Type = IMAGE_SYM_TYPE_NULL;
+    Sym.StorageClass = IMAGE_SYM_CLASS_EXTERNAL;
+  }
+  Sym.NumberOfAuxSymbols = 0;
+
+  switch (Def->kind()) {
+  case Symbol::DefinedAbsoluteKind:
+    Sym.Value = Def->getRVA();
+    Sym.SectionNumber = IMAGE_SYM_ABSOLUTE;
+    break;
+  default: {
+    uint64_t RVA = Def->getRVA();
+    OutputSection *Sec = nullptr;
+    for (OutputSection *S : OutputSections) {
+      if (S->getRVA() > RVA)
+        break;
+      Sec = S;
+    }
+    Sym.Value = RVA - Sec->getRVA();
+    Sym.SectionNumber = Sec->SectionIndex;
+    break;
+  }
+  }
+  return Sym;
+}
+
+void Writer::createSymbolAndStringTable() {
   // Name field in the section table is 8 byte long. Longer names need
   // to be written to the string table. First, construct string table.
   for (OutputSection *Sec : OutputSections) {
     StringRef Name = Sec->getName();
     if (Name.size() <= COFF::NameSize)
       continue;
     // If a section isn't discardable (i.e. will be mapped at runtime),
     // prefer a truncated section name over a long section name in
     // the string table that is unavailable at runtime. This is different from
     // what link.exe does, but finding ".eh_fram" instead of "/4" is useful
     // to libunwind.
     if ((Sec->getPermissions() & IMAGE_SCN_MEM_DISCARDABLE) == 0)
       continue;
-    Sec->setStringTableOff(Strtab.size() + 4); // +4 for the size field
-    Strtab.insert(Strtab.end(), Name.begin(), Name.end());
-    Strtab.push_back('\0');
+    Sec->setStringTableOff(addEntryToStringTable(Name));
+  }
+
+  if (Config->DebugDwarf) {
+    for (ObjFile *File : ObjFile::Instances) {
+      for (Symbol *B : File->getSymbols()) {
+        auto *D = dyn_cast_or_null<Defined>(B);
+        if (!D || D->WrittenToSymtab)
+          continue;
+        D->WrittenToSymtab = true;
+
+        if (Optional<coff_symbol16> Sym = createSymbol(D))
+          OutputSymtab.push_back(*Sym);
+      }
+    }
   }
 
-  if (Strtab.empty())
+  if (OutputSymtab.empty() && Strtab.empty())
     return;
 
   OutputSection *LastSection = OutputSections.back();
-  // We position the string table to be adjacent to the end of the last section.
-  PointerToStringTable = LastSection->getFileOff() +
-                         alignTo(LastSection->getRawSize(), SectorSize);
-  FileSize = alignTo(PointerToStringTable + Strtab.size() + 4, SectorSize);
+  // We position the symbol table to be adjacent to the end of the last section.
+  uint64_t FileOff = LastSection->getFileOff() +
+  PointerToSymbolTable = FileOff;
+  FileOff += OutputSymtab.size() * sizeof(coff_symbol16);
+  FileOff += 4 + Strtab.size();
+  FileSize = alignTo(FileOff, SectorSize);
 }
 
 // Visits all sections to assign incremental, non-overlapping RVAs and
 // file offsets.
 void Writer::assignAddresses() {
   SizeOfHeaders = DOSStubSize + sizeof(PEMagic) + sizeof(coff_file_header) +
                   sizeof(data_directory) * NumberfOfDataDirectory +
                   sizeof(coff_section) * OutputSections.size();
template <typename PEHeaderTy> void Writer::writeHeader() {
   // Write section table
   for (OutputSection *Sec : OutputSections) {
     Sec->writeHeaderTo(Buf);
     Buf += sizeof(coff_section);
   }
   SectionTable = ArrayRef<uint8_t>(
       Buf - OutputSections.size() * sizeof(coff_section), Buf);
 
-  // The string table normally follows the symbol table, but because we always
-  // emit an empty symbol table, the string table appears at the location of the
-  // symbol table.
-  COFF->PointerToSymbolTable = PointerToStringTable;
-  COFF->NumberOfSymbols = 0;
-  if (Strtab.empty())
+  if (OutputSymtab.empty() && Strtab.empty())
     return;
 
-  auto *StringTable = Buffer->getBufferStart() + PointerToStringTable;
-  // Create the string table. The first 4 bytes is length including itself.
-  write32le(StringTable, Strtab.size() + 4);
-  memcpy(StringTable + 4, Strtab.data(), Strtab.size());
+  COFF->PointerToSymbolTable = PointerToSymbolTable;
+  uint32_t NumberOfSymbols = OutputSymtab.size();
+  COFF->NumberOfSymbols = NumberOfSymbols;
+  auto *SymbolTable = reinterpret_cast<coff_symbol16 *>(
+      Buffer->getBufferStart() + COFF->PointerToSymbolTable);
+  for (size_t I = 0; I != NumberOfSymbols; ++I)
+    SymbolTable[I] = OutputSymtab[I];
+  // Create the string table, it follows immediately after the symbol table.
+  // The first 4 bytes is length including itself.
+  Buf = reinterpret_cast<uint8_t *>(&SymbolTable[NumberOfSymbols]);
+  write32le(Buf, Strtab.size() + 4);
+  if (!Strtab.empty())
+    memcpy(Buf + 4, Strtab.data(), Strtab.size());
 }
 
 void Writer::openFile(StringRef Path) {
   Buffer = check(
       FileOutputBuffer::create(Path, FileSize, FileOutputBuffer::F_executable),
       "failed to open " + Path);
 }
 

lld/test/COFF/strtab-size.s

+# REQUIRES: x86
+
+# Test that the strtab size is included in the allocation even if the
+# strtab itself is empty. To achieve this, we need a number of symbols N
+# where alignTo(N*18, 512) < alignTo(N*18 + 4, 512), where the first
+# positive N fulfilling that is 199.
+
+# RUN: llvm-mc -triple=x86_64-windows-msvc %s -filetype=obj -o %t.obj
+# RUN: lld-link -out:%t.exe -entry:main %t.obj -debug:dwarf
+
+# If the size of the strtab isn't allocated for, llvm-readobj would
+# output SymbolCount: 0 (and dumpbin.exe would error out with "invalid file
+# or disk full, cannot seek to 0x1602").
+
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck %s
+# CHECK: SymbolCount: 199
+
+.global main
+.text
+main:
+sym0:
+sym1:
+sym2:
+sym3:
+sym4:
+sym5:
+sym6:
+sym7:
+sym8:
+sym9:
+sym10:
+sym11:
+sym12:
+sym13:
+sym14:
+sym15:
+sym16:
+sym17:
+sym18:
+sym19:
+sym20:
+sym21:
+sym22:
+sym23:
+sym24:
+sym25:
+sym26:
+sym27:
+sym28:
+sym29:
+sym30:
+sym31:
+sym32:
+sym33:
+sym34:
+sym35:
+sym36:
+sym37:
+sym38:
+sym39:
+sym40:
+sym41:
+sym42:
+sym43:
+sym44:
+sym45:
+sym46:
+sym47:
+sym48:
+sym49:
+sym50:
+sym51:
+sym52:
+sym53:
+sym54:
+sym55:
+sym56:
+sym57:
+sym58:
+sym59:
+sym60:
+sym61:
+sym62:
+sym63:
+sym64:
+sym65:
+sym66:
+sym67:
+sym68:
+sym69:
+sym70:
+sym71:
+sym72:
+sym73:
+sym74:
+sym75:
+sym76:
+sym77:
+sym78:
+sym79:
+sym80:
+sym81:
+sym82:
+sym83:
+sym84:
+sym85:
+sym86:
+sym87:
+sym88:
+sym89:
+sym90:
+sym91:
+sym92:
+sym93:
+sym94:
+sym95:
+sym96:
+sym97:
+sym98:
+sym99:
+sym100:
+sym101:
+sym102:
+sym103:
+sym104:
+sym105:
+sym106:
+sym107:
+sym108:
+sym109:
+sym110:
+sym111:
+sym112:
+sym113:
+sym114:
+sym115:
+sym116:
+sym117:
+sym118:
+sym119:
+sym120:
+sym121:
+sym122:
+sym123:
+sym124:
+sym125:
+sym126:
+sym127:
+sym128:
+sym129:
+sym130:
+sym131:
+sym132:
+sym133:
+sym134:
+sym135:
+sym136:
+sym137:
+sym138:
+sym139:
+sym140:
+sym141:
+sym142:
+sym143:
+sym144:
+sym145:
+sym146:
+sym147:
+sym148:
+sym149:
+sym150:
+sym151:
+sym152:
+sym153:
+sym154:
+sym155:
+sym156:
+sym157:
+sym158:
+sym159:
+sym160:
+sym161:
+sym162:
+sym163:
+sym164:
+sym165:
+sym166:
+sym167:
+sym168:
+sym169:
+sym170:
+sym171:
+sym172:
+sym173:
+sym174:
+sym175:
+sym176:
+sym177:
+sym178:
+sym179:
+sym180:
+sym181:
+sym182:
+sym183:
+sym184:
+sym185:
+sym186:
+sym187:
+sym188:
+sym189:
+sym190:
+sym191:
+sym192:
+sym193:
+sym194:
+  ret

lld/test/COFF/symtab.test

+# RUN: yaml2obj < %s > %t.obj
+# RUN: lld-link /debug:dwarf /out:%t.exe /entry:main %t.obj %p/Inputs/std64.lib
+# RUN: llvm-readobj -symbols %t.exe | FileCheck %s
+# RUN: lld-link /debug:dwarf /opt:noref /out:%t.exe /entry:main %t.obj %p/Inputs/std64.lib
+# RUN: llvm-readobj -symbols %t.exe | FileCheck %s
+
+# RUN: lld-link /debug /out:%t.exe /entry:main %t.obj %p/Inputs/std64.lib
+# RUN: llvm-readobj -symbols %t.exe | FileCheck -check-prefix=NO %s
+
+# CHECK:      Symbols [
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: .text
+# CHECK-NEXT:     Value: 0
+# CHECK-NEXT:     Section: .text (2)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: Static (0x3)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: .text2
+# CHECK-NEXT:     Value: 0
+# CHECK-NEXT:     Section: .text (2)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: Static (0x3)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: .data
+# CHECK-NEXT:     Value: 0
+# CHECK-NEXT:     Section: .data (1)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: Static (0x3)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: MessageBoxA
+# CHECK-NEXT:     Value: 80
+# CHECK-NEXT:     Section: .text (2)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: External (0x2)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: ExitProcess
+# CHECK-NEXT:     Value: 64
+# CHECK-NEXT:     Section: .text (2)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: External (0x2)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: message
+# CHECK-NEXT:     Value: 6
+# CHECK-NEXT:     Section: .text2 (3)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: Static (0x3)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: main
+# CHECK-NEXT:     Value: 0
+# CHECK-NEXT:     Section: .text (2)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: External (0x2)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: caption
+# CHECK-NEXT:     Value: 0
+# CHECK-NEXT:     Section: .text2 (3)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: Static (0x3)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Name: abs_symbol
+# CHECK-NEXT:     Value: 2662186735
+# CHECK-NEXT:     Section: IMAGE_SYM_ABSOLUTE (-1)
+# CHECK-NEXT:     BaseType: Null (0x0)
+# CHECK-NEXT:     ComplexType: Null (0x0)
+# CHECK-NEXT:     StorageClass: External (0x2)
+# CHECK-NEXT:     AuxSymbolCount: 0
+# CHECK-NEXT:   }
+# CHECK-NEXT: ]
+
+# NO: Symbols [
+
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: []
+sections:
+  - Name:            .text
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       4096
+    SectionData:     B800000000000000005068000000000000000068000000000000000050E8000000000000000050E8000000000000000050E80000000000000000
+    Relocations:
+      - VirtualAddress:  0
+        SymbolName:      abs_symbol
+        Type:            IMAGE_REL_AMD64_ADDR64
+      - VirtualAddress:  7
+        SymbolName:      caption
+        Type:            IMAGE_REL_AMD64_ADDR64
+      - VirtualAddress:  12
+        SymbolName:      message
+        Type:            IMAGE_REL_AMD64_ADDR64
+      - VirtualAddress:  18
+        SymbolName:      MessageBoxA
+        Type:            IMAGE_REL_AMD64_REL32
+      - VirtualAddress:  24
+        SymbolName:      ExitProcess
+        Type:            IMAGE_REL_AMD64_REL32
+      - VirtualAddress:  30
+        SymbolName:      __ImageBase
+        Type:            IMAGE_REL_AMD64_ADDR64
+  - Name:            .text2
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       4096
+    SectionData:     B800000000000000005068000000000000000068000000000000000050E8000000000000000050E8000000000000000050E80000000000000000
+    Relocations:
+      - VirtualAddress:  0
+        SymbolName:      abs_symbol
+        Type:            IMAGE_REL_AMD64_ADDR64
+      - VirtualAddress:  7
+        SymbolName:      caption
+        Type:            IMAGE_REL_AMD64_ADDR64
+      - VirtualAddress:  12
+        SymbolName:      message
+        Type:            IMAGE_REL_AMD64_ADDR64
+      - VirtualAddress:  18
+        SymbolName:      MessageBoxA
+        Type:            IMAGE_REL_AMD64_REL32
+      - VirtualAddress:  24
+        SymbolName:      ExitProcess
+        Type:            IMAGE_REL_AMD64_REL32
+      - VirtualAddress:  30
+        SymbolName:      __ImageBase
+        Type:            IMAGE_REL_AMD64_ADDR64
+  - Name:            .data
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ, IMAGE_SCN_MEM_WRITE ]
+    Alignment:       4
+    SectionData:     48656C6C6F0048656C6C6F20576F726C6400
+symbols:
+  - Name:            "@comp.id"
+    Value:           10394907
+    SectionNumber:   65535
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+  - Name:            .text
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          28
+      NumberOfRelocations: 6
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            .text2
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          28
+      NumberOfRelocations: 6
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            .data
+    Value:           0
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