[LLD][COFF] Cleanup error messages / add more coverage tests

[aganea]

Summary

Changes summary:

1. Log the reason for a PDB or precompiled-OBJ load failure. The format looks like this:

lld-link: warning: Cannot use debug info for 'pdb-type-server-missing.yaml.tmp1.obj'
>>> failed to load reference 'C:\src\llvm-project\build\definitely_not_found_for_sure.pdb': no such file or directory.

2. Properly handle out-of-date PDB or precompiled-OBJ signature by displaying a corresponding error:

lld-link: warning: Cannot use debug info for 'pdb-type-server-invalid-signature.yaml.tmp.obj'
>>> failed to load reference 'pdb-diff-cl.pdb': The signature does not match; the file(s) might be out of date.

3. Slightly change behavior on PDB failure: any subsequent load attempt from another OBJ would result in the same error message being logged:

lld-link: warning: Cannot use debug info for 'pdb-type-server-missing.yaml.tmp1.obj'
>>> failed to load reference 'C:\src\llvm-project\build\definitely_not_found_for_sure.pdb': no such file or directory.

lld-link: warning: Cannot use debug info for 'pdb-type-server-missing.yaml.tmp2.obj'
>>> failed to load reference 'C:\src\llvm-project\build\definitely_not_found_for_sure.pdb': no such file or directory.

4. Slightly change behavior on PDB failure: retry with filename only if previous error was ENOENT ("no such file or directory")

5. Tests: a. for native PDB errors; b. cover all the cases above.

[ruiu]

COFF/PDB.cpp

168

We generally don't use std::map because it's slower than llvm::DenseMap and in most cases we don't need an ordered map (std::map is ordered). But this use may be okay because original code uses std::set. Or, we don't need to care about it at all if the number of data inserted into this map/set is small. Zach?

[zturner]

It's probably fine because there's only going to be a handful of items in the map. I mildly prefer the LLVM ones, but I also don't care that much.

COFF/PDB.cpp

private:
 
   std::vector<pdb::SecMapEntry> SectionMap;
 
   /// Type index mappings of type server PDBs that we've loaded so far.
   std::map<GUID, CVIndexMap> TypeServerIndexMappings;
 
   /// List of TypeServer PDBs which cannot be loaded.
   /// Cached to prevent repeated load attempts.
-  std::set<GUID> MissingTypeServerPDBs;
+  std::map<GUID, std::string> MissingTypeServerPDBs;
 };
 }
 
 static SectionChunk *findByName(ArrayRef<SectionChunk *> Sections,
                                 StringRef Name) {
   for (SectionChunk *C : Sections)
     if (C->getSectionName() == Name)
       return C;
tryToLoadPDB(const GUID &GuidFromObj, StringRef TSPath) {
   // All PDB Files should have an Info stream.
   if (!ExpectedInfo)
     return ExpectedInfo.takeError();
 
   // Just because a file with a matching name was found and it was an actual
   // PDB file doesn't mean it matches.  For it to match the InfoStream's GUID
   // must match the GUID specified in the TypeServer2 record.
   if (ExpectedInfo->getGuid() != GuidFromObj)
-    return make_error<pdb::PDBError>(
-        pdb::pdb_error_code::type_server_not_found, TSPath);
+    return make_error<pdb::PDBError>(pdb::pdb_error_code::signature_out_of_date,
+                                     TSPath);
 
   return std::move(NS);
 }
 
 Expected<const CVIndexMap&> PDBLinker::maybeMergeTypeServerPDB(ObjFile *File,
                                                                TypeServer2Record &TS) {
-  const GUID& TSId = TS.getGuid();
+  const GUID &TSId = TS.getGuid();
   StringRef TSPath = TS.getName();
 
   // First, check if the PDB has previously failed to load.
-  if (MissingTypeServerPDBs.count(TSId))
-    return make_error<pdb::PDBError>(
-      pdb::pdb_error_code::type_server_not_found, TSPath);
+  auto PrevErr = MissingTypeServerPDBs.find(TSId);
+  if (PrevErr != MissingTypeServerPDBs.end())
+    return createFileError(
+        TSPath, std::move(make_error<StringError>(PrevErr->second,
+                                                  inconvertibleErrorCode())));
 
   // Second, check if we already loaded a PDB with this GUID. Return the type
   // index mapping if we have it.
   auto Insertion = TypeServerIndexMappings.insert({TSId, CVIndexMap()});
   CVIndexMap &IndexMap = Insertion.first->second;
   if (!Insertion.second)
     return IndexMap;
 
   // Mark this map as a type server map.
   IndexMap.IsTypeServerMap = true;
 
   // Check for a PDB at:
   // 1. The given file path
   // 2. Next to the object file or archive file
-  auto ExpectedSession = tryToLoadPDB(TSId, TSPath);
-  if (!ExpectedSession) {
-    consumeError(ExpectedSession.takeError());
+  auto ExpectedSession = handleExpected(
+      tryToLoadPDB(TSId, TSPath),
+      [&]() {
         StringRef LocalPath =
             !File->ParentName.empty() ? File->ParentName : File->getName();
         SmallString<128> Path = sys::path::parent_path(LocalPath);
         sys::path::append(
             Path, sys::path::filename(TSPath, sys::path::Style::windows));
-    ExpectedSession = tryToLoadPDB(TSId, Path);
-  }
+        return tryToLoadPDB(TSId, Path);
+      },
+      [&](std::unique_ptr<ECError> EC) -> Error {
+        auto SysErr = EC->convertToErrorCode();
+        // Only re-try loading if the previous error was "No such file or
+        // directory"
+        if (SysErr.category() == std::generic_category() &&
+            SysErr.value() == ENOENT)
+          return Error::success();
+        return Error(std::move(EC));
+      });
+
   if (auto E = ExpectedSession.takeError()) {
     TypeServerIndexMappings.erase(TSId);
-    MissingTypeServerPDBs.emplace(TSId);
-    return std::move(E);
+
+    // Flatten the error to a string, for later display, if the error occurs
+    // again on the same PDB.
+    std::string ErrMsg;
+    raw_string_ostream S(ErrMsg);
+    S << E;
+    auto It = MissingTypeServerPDBs.emplace(TSId, S.str());
+
+    return createFileError(TSPath, std::move(E));
   }
 
   pdb::NativeSession *Session = ExpectedSession->get();
 
   // Keep a strong reference to this PDB, so that it's safe to hold pointers
   // into the file.
   LoadedPDBs.push_back(std::move(*ExpectedSession));
 
void PDBLinker::addObjFile(ObjFile *File) {
   // type information, file checksums, and the string table.  Add type info to
   // the PDB first, so that we can get the map from object file type and item
   // indices to PDB type and item indices.
   CVIndexMap ObjectIndexMap;
   auto IndexMapResult = mergeDebugT(File, ObjectIndexMap);
 
   // If the .debug$T sections fail to merge, assume there is no debug info.
   if (!IndexMapResult) {
-    warn("Type server PDB for " + Name + " is invalid, ignoring debug info. " +
-         toString(IndexMapResult.takeError()));
+    auto FileName = sys::path::filename(Path);
+    warn("Cannot use debug info for '" + FileName + "'\n" +
+         ">>> failed to load reference " +
+         StringRef(toString(IndexMapResult.takeError())) + ".");
     return;
   }
 
   const CVIndexMap &IndexMap = *IndexMapResult;
 
   ScopedTimer T(SymbolMergingTimer);
 
   // Now do all live .debug$S sections.

test/COFF/Inputs/bad-block-size.pdb

+Microsoft C/C++ MSF 7.00
+␚DS
 No newline at end of file

test/COFF/Inputs/pdb-type-server-missing-2.yaml

+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            '.debug$T'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Types:
+      - Kind:            LF_TYPESERVER2
+        TypeServer2:
+          Guid:            '{01DF191B-22BF-6B42-96CE-5258B8329FE5}'
+          Age:             18
+          Name:            'C:\src\llvm-project\build\definitely_not_found_for_sure.pdb'
+  - Name:            '.text$mn'
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     33C0C3
+symbols:
+  - Name:            '.debug$T'
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          564
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+...

test/COFF/Inputs/pdb-type-server-valid-signature.yaml

+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            '.debug$S'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Subsections:
+      - !Symbols
+        Records:
+          - Kind:            S_GPROC32_ID
+            ProcSym:
+              CodeSize:        3
+              DbgStart:        0
+              DbgEnd:          2
+              FunctionType:    4199
+              Flags:           [  ]
+              DisplayName:     main
+          - Kind:            S_FRAMEPROC
+            FrameProcSym:
+              TotalFrameBytes: 0
+              PaddingFrameBytes: 0
+              OffsetToPadding: 0
+              BytesOfCalleeSavedRegisters: 0
+              OffsetOfExceptionHandler: 0
+              SectionIdOfExceptionHandler: 0
+              Flags:           [ AsynchronousExceptionHandling, OptimizedForSpeed ]
+          - Kind:            S_PROC_ID_END
+            ScopeEndSym:
+      - !Lines
+        CodeSize:        3
+        Flags:           [  ]
+        RelocOffset:     0
+        RelocSegment:    0
+        Blocks:
+          - FileName:        'c:\src\llvm-project\build\t.c'
+            Lines:
+              - Offset:          0
+                LineStart:       1
+                IsStatement:     true
+                EndDelta:        0
+            Columns:
+      - !FileChecksums
+        Checksums:
+          - FileName:        'c:\src\llvm-project\build\t.c'
+            Kind:            MD5
+            Checksum:        270A878DCC1B845655B162F56C4F5020
+      - !StringTable
+        Strings:
+          - 'c:\src\llvm-project\build\t.c'
+    Relocations:
+      - VirtualAddress:  44
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  48
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+      - VirtualAddress:  100
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  104
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+  - Name:            '.debug$T'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Types:
+      - Kind:            LF_TYPESERVER2
+        TypeServer2:
+          Guid:            '{8DABD2A0-28FF-CB43-9BAF-175B77B76414}'
+          Age:             18
+          Name:            'pdb-diff-cl.pdb'
+  - Name:            '.text$mn'
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     33C0C3
+symbols:
+  - Name:            '.debug$S'
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          328
+      NumberOfRelocations: 4
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$T'
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          564
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.text$mn'
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          3
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        4021952397
+      Number:          0
+  - Name:            main
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...

test/COFF/pdb-type-server-invalid-signature.yaml

+
+# RUN: cd %S/Inputs
+# RUN: yaml2obj %s -o %t.obj
+# RUN: lld-link %t.obj -out:%t.exe -debug -pdb:%t.pdb -nodefaultlib -entry:main 2>&1 | FileCheck %s
+# RUN: cd %S
+
+# CHECK: warning: Cannot use debug info for {{.*}}.obj
+# CHECK-NEXT: The signature does not match; the file(s) might be out of date
+
+# Also test a valid match
+
+# RUN: cd %S/Inputs
+# RUN: yaml2obj %S/Inputs/pdb-type-server-valid-signature.yaml -o %t2.obj
+# RUN: lld-link %t2.obj -out:%t2.exe -debug -pdb:%t2.pdb -nodefaultlib -entry:main 2>&1 | FileCheck %s -check-prefix=VALID-SIGNATURE -allow-empty
+# RUN: cd %S
+
+# VALID-SIGNATURE-NOT: warning: Cannot use debug info for {{.*}}.obj
+# VALID-SIGNATURE-NOT: The signature does not match; the file(s) might be out of date
+
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            '.debug$S'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Subsections:
+      - !Symbols
+        Records:
+          - Kind:            S_GPROC32_ID
+            ProcSym:
+              CodeSize:        3
+              DbgStart:        0
+              DbgEnd:          2
+              FunctionType:    4199
+              Flags:           [  ]
+              DisplayName:     main
+          - Kind:            S_FRAMEPROC
+            FrameProcSym:
+              TotalFrameBytes: 0
+              PaddingFrameBytes: 0
+              OffsetToPadding: 0
+              BytesOfCalleeSavedRegisters: 0
+              OffsetOfExceptionHandler: 0
+              SectionIdOfExceptionHandler: 0
+              Flags:           [ AsynchronousExceptionHandling, OptimizedForSpeed ]
+          - Kind:            S_PROC_ID_END
+            ScopeEndSym:
+      - !Lines
+        CodeSize:        3
+        Flags:           [  ]
+        RelocOffset:     0
+        RelocSegment:    0
+        Blocks:
+          - FileName:        'c:\src\llvm-project\build\t.c'
+            Lines:
+              - Offset:          0
+                LineStart:       1
+                IsStatement:     true
+                EndDelta:        0
+            Columns:
+      - !FileChecksums
+        Checksums:
+          - FileName:        'c:\src\llvm-project\build\t.c'
+            Kind:            MD5
+            Checksum:        270A878DCC1B845655B162F56C4F5020
+      - !StringTable
+        Strings:
+          - 'c:\src\llvm-project\build\t.c'
+    Relocations:
+      - VirtualAddress:  44
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  48
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+      - VirtualAddress:  100
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  104
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+  - Name:            '.debug$T'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Types:
+      - Kind:            LF_TYPESERVER2
+        TypeServer2:
+          Guid:            '{01DF191B-22BF-6B42-96CE-5258B8329FE5}'
+          Age:             18
+          Name:            'pdb-diff-cl.pdb'
+  - Name:            '.text$mn'
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     33C0C3
+symbols:
+  - Name:            '.debug$S'
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          328
+      NumberOfRelocations: 4
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$T'
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          564
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.text$mn'
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          3
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        4021952397
+      Number:          0
+  - Name:            main
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...

test/COFF/pdb-type-server-missing.yaml

 # This is an object compiled with /Zi (see the LF_TYPESERVER2 record) without an
 # adjacent type server PDB. Test that LLD fails gracefully on it.
+# Also try linking another OBJ with a reference to the same PDB
 
-# RUN: yaml2obj %s -o %t.obj
-# RUN: lld-link %t.obj -out:%t.exe -debug -pdb:%t.pdb -nodefaultlib -entry:main 2>&1 | FileCheck %s
+# RUN: yaml2obj %s -o %t1.obj
+# RUN: yaml2obj %p/Inputs/pdb-type-server-missing-2.yaml -o %t2.obj
+# RUN: lld-link %t1.obj %t2.obj -out:%t.exe -debug -pdb:%t.pdb -nodefaultlib -entry:main 2>&1 | FileCheck %s
 
-# CHECK: warning: Type server PDB for {{.*}}.obj is invalid, ignoring debug info.
+# CHECK: warning: Cannot use debug info for {{.*}}.obj
+# CHECK-NEXT: {{N|n}}o such file or directory
+
+# CHECK: warning: Cannot use debug info for {{.*}}.obj
+# CHECK-NEXT: {{N|n}}o such file or directory
 
 --- !COFF
 header:
   Machine:         IMAGE_FILE_MACHINE_AMD64
   Characteristics: [  ]
 sections:
   - Name:            '.debug$S'
     Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]

test/COFF/pdb-type-server-native-errors.yaml

+
+# RUN: cd %S/Inputs
+# RUN: yaml2obj %s -o %t.obj
+# RUN: lld-link %t.obj -out:%t.exe -debug -pdb:%t.pdb -nodefaultlib -entry:main 2>&1 | FileCheck %s
+# RUN: cd %S
+
+# CHECK: warning: Cannot use debug info for {{.*}}.obj
+# CHECK-NEXT: The PDB file is corrupt. MSF superblock is missing
+
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            '.debug$S'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Subsections:
+      - !Symbols
+        Records:
+          - Kind:            S_GPROC32_ID
+            ProcSym:
+              CodeSize:        3
+              DbgStart:        0
+              DbgEnd:          2
+              FunctionType:    4199
+              Flags:           [  ]
+              DisplayName:     main
+          - Kind:            S_FRAMEPROC
+            FrameProcSym:
+              TotalFrameBytes: 0
+              PaddingFrameBytes: 0
+              OffsetToPadding: 0
+              BytesOfCalleeSavedRegisters: 0
+              OffsetOfExceptionHandler: 0
+              SectionIdOfExceptionHandler: 0
+              Flags:           [ AsynchronousExceptionHandling, OptimizedForSpeed ]
+          - Kind:            S_PROC_ID_END
+            ScopeEndSym:
+      - !Lines
+        CodeSize:        3
+        Flags:           [  ]
+        RelocOffset:     0
+        RelocSegment:    0
+        Blocks:
+          - FileName:        'c:\src\llvm-project\build\t.c'
+            Lines:
+              - Offset:          0
+                LineStart:       1
+                IsStatement:     true
+                EndDelta:        0
+            Columns:
+      - !FileChecksums
+        Checksums:
+          - FileName:        'c:\src\llvm-project\build\t.c'
+            Kind:            MD5
+            Checksum:        270A878DCC1B845655B162F56C4F5020
+      - !StringTable
+        Strings:
+          - 'c:\src\llvm-project\build\t.c'
+    Relocations:
+      - VirtualAddress:  44
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  48
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+      - VirtualAddress:  100
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  104
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+  - Name:            '.debug$T'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Types:
+      - Kind:            LF_TYPESERVER2
+        TypeServer2:
+          Guid:            '{01DF191B-22BF-6B42-96CE-5258B8329FE5}'
+          Age:             18
+          Name:            'bad-block-size.pdb'
+  - Name:            '.text$mn'
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     33C0C3
+symbols:
+  - Name:            '.debug$S'
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          328
+      NumberOfRelocations: 4
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$T'
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          564
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.text$mn'
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          3
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        4021952397
+      Number:          0
+  - Name:            main
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...