llvm-project/llvm/tools/llvm-pdbutil/Diff.cpp

646 lines
23 KiB
C++

//===- Diff.cpp - PDB diff utility ------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Diff.h"
#include "DiffPrinter.h"
#include "FormatUtil.h"
#include "StreamUtil.h"
#include "llvm-pdbutil.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/DebugInfo/PDB/Native/DbiStream.h"
#include "llvm/DebugInfo/PDB/Native/Formatters.h"
#include "llvm/DebugInfo/PDB/Native/InfoStream.h"
#include "llvm/DebugInfo/PDB/Native/PDBFile.h"
#include "llvm/DebugInfo/PDB/Native/PDBStringTable.h"
#include "llvm/DebugInfo/PDB/Native/RawConstants.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FormatAdapters.h"
#include "llvm/Support/FormatProviders.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/Path.h"
using namespace llvm;
using namespace llvm::pdb;
namespace {
// Compare and format two stream numbers. Stream numbers are considered
// identical if they contain the same value, equivalent if they are both
// the invalid stream or neither is the invalid stream, and different if
// one is the invalid stream and another isn't.
struct StreamNumberProvider {
static DiffResult compare(uint16_t L, uint16_t R) {
if (L == R)
return DiffResult::IDENTICAL;
bool LP = L != kInvalidStreamIndex;
bool RP = R != kInvalidStreamIndex;
if (LP != RP)
return DiffResult::DIFFERENT;
return DiffResult::EQUIVALENT;
}
static std::string format(uint16_t SN, bool Right) {
if (SN == kInvalidStreamIndex)
return "(not present)";
return formatv("{0}", SN).str();
}
};
// Compares and formats two module indices. Modis are considered identical
// if they are identical, equivalent if they either both contain a value or
// both don't contain a value, and different if one contains a value and the
// other doesn't.
struct ModiProvider {
DiffResult compare(Optional<uint32_t> L, Optional<uint32_t> R) {
if (L == R)
return DiffResult::IDENTICAL;
if (L.hasValue() != R.hasValue())
return DiffResult::DIFFERENT;
return DiffResult::EQUIVALENT;
}
std::string format(Optional<uint32_t> Modi, bool Right) {
if (!Modi.hasValue())
return "(not present)";
return formatv("{0}", *Modi).str();
}
};
// Compares and formats two paths embedded in the PDB, ignoring the beginning
// of the path if the user specified it as a "root path" on the command line.
struct BinaryPathProvider {
explicit BinaryPathProvider(uint32_t MaxLen) : MaxLen(MaxLen) {}
DiffResult compare(StringRef L, StringRef R) {
if (L == R)
return DiffResult::IDENTICAL;
SmallString<64> LN = removeRoot(L, false);
SmallString<64> RN = removeRoot(R, true);
return (LN.equals_lower(RN)) ? DiffResult::EQUIVALENT
: DiffResult::DIFFERENT;
}
std::string format(StringRef S, bool Right) {
if (S.empty())
return "(empty)";
SmallString<64> Native = removeRoot(S, Right);
return truncateStringFront(Native.str(), MaxLen);
}
SmallString<64> removeRoot(StringRef Path, bool IsRight) const {
SmallString<64> Native(Path);
auto &RootOpt = IsRight ? opts::diff::RightRoot : opts::diff::LeftRoot;
SmallString<64> Root(static_cast<std::string>(RootOpt));
// pdb paths always use windows syntax, convert slashes to backslashes.
sys::path::native(Root, sys::path::Style::windows);
if (sys::path::has_stem(Root, sys::path::Style::windows))
sys::path::append(Root, sys::path::Style::windows,
sys::path::get_separator(sys::path::Style::windows));
sys::path::replace_path_prefix(Native, Root, "", sys::path::Style::windows);
return Native;
}
uint32_t MaxLen;
};
// Compare and format two stream purposes. For general streams, this just
// compares the description. For module streams it uses the path comparison
// algorithm taking into consideration the binary root, described above.
// Formatting stream purposes just prints the stream purpose, except for
// module streams and named streams, where it prefixes the name / module
// with an identifier. Example:
//
// Named Stream "\names"
// Module Stream "foo.obj"
//
// If a named stream is too long to fit in a column, it is truncated at the
// end, and if a module is too long to fit in a column, it is truncated at the
// beginning. Example:
//
// Named Stream "\Really Long Str..."
// Module Stream "...puts\foo.obj"
//
struct StreamPurposeProvider {
explicit StreamPurposeProvider(uint32_t MaxLen) : MaxLen(MaxLen) {}
DiffResult compare(const StreamInfo &L, const StreamInfo &R) {
if (L.getPurpose() != R.getPurpose())
return DiffResult::DIFFERENT;
if (L.getPurpose() == StreamPurpose::ModuleStream) {
BinaryPathProvider PathProvider(MaxLen);
return PathProvider.compare(L.getShortName(), R.getShortName());
}
return (L.getShortName() == R.getShortName()) ? DiffResult::IDENTICAL
: DiffResult::DIFFERENT;
}
std::string format(const StreamInfo &P, bool Right) {
if (P.getPurpose() == StreamPurpose::Other ||
P.getPurpose() == StreamPurpose::Symbols)
return truncateStringBack(P.getShortName(), MaxLen);
if (P.getPurpose() == StreamPurpose::NamedStream)
return truncateQuotedNameBack("Named Stream", P.getShortName(), MaxLen);
assert(P.getPurpose() == StreamPurpose::ModuleStream);
uint32_t ExtraChars = strlen("Module \"\"");
BinaryPathProvider PathProvider(MaxLen - ExtraChars);
std::string Result = PathProvider.format(P.getShortName(), Right);
return formatv("Module \"{0}\"", Result);
}
uint32_t MaxLen;
};
} // namespace
namespace llvm {
template <> struct format_provider<PdbRaw_FeatureSig> {
static void format(const PdbRaw_FeatureSig &Sig, raw_ostream &Stream,
StringRef Style) {
switch (Sig) {
case PdbRaw_FeatureSig::MinimalDebugInfo:
Stream << "MinimalDebugInfo";
break;
case PdbRaw_FeatureSig::NoTypeMerge:
Stream << "NoTypeMerge";
break;
case PdbRaw_FeatureSig::VC110:
Stream << "VC110";
break;
case PdbRaw_FeatureSig::VC140:
Stream << "VC140";
break;
}
}
};
}
template <typename R> using ValueOfRange = llvm::detail::ValueOfRange<R>;
DiffStyle::DiffStyle(PDBFile &File1, PDBFile &File2)
: File1(File1), File2(File2) {}
Error DiffStyle::dump() {
if (auto EC = diffSuperBlock())
return EC;
if (auto EC = diffFreePageMap())
return EC;
if (auto EC = diffStreamDirectory())
return EC;
if (auto EC = diffStringTable())
return EC;
if (auto EC = diffInfoStream())
return EC;
if (auto EC = diffDbiStream())
return EC;
if (auto EC = diffSectionContribs())
return EC;
if (auto EC = diffSectionMap())
return EC;
if (auto EC = diffFpoStream())
return EC;
if (auto EC = diffTpiStream(StreamTPI))
return EC;
if (auto EC = diffTpiStream(StreamIPI))
return EC;
if (auto EC = diffPublics())
return EC;
if (auto EC = diffGlobals())
return EC;
return Error::success();
}
Error DiffStyle::diffSuperBlock() {
DiffPrinter D(2, "MSF Super Block", 16, 20, opts::diff::PrintResultColumn,
opts::diff::PrintValueColumns, outs());
D.printExplicit("File", DiffResult::UNSPECIFIED,
truncateStringFront(File1.getFilePath(), 18),
truncateStringFront(File2.getFilePath(), 18));
D.print("Block Size", File1.getBlockSize(), File2.getBlockSize());
D.print("Block Count", File1.getBlockCount(), File2.getBlockCount());
D.print("Unknown 1", File1.getUnknown1(), File2.getUnknown1());
D.print("Directory Size", File1.getNumDirectoryBytes(),
File2.getNumDirectoryBytes());
return Error::success();
}
Error DiffStyle::diffStreamDirectory() {
DiffPrinter D(2, "Stream Directory", 30, 20, opts::diff::PrintResultColumn,
opts::diff::PrintValueColumns, outs());
D.printExplicit("File", DiffResult::UNSPECIFIED,
truncateStringFront(File1.getFilePath(), 18),
truncateStringFront(File2.getFilePath(), 18));
SmallVector<StreamInfo, 32> P;
SmallVector<StreamInfo, 32> Q;
discoverStreamPurposes(File1, P);
discoverStreamPurposes(File2, Q);
D.print("Stream Count", File1.getNumStreams(), File2.getNumStreams());
auto PI = to_vector<32>(enumerate(P));
auto QI = to_vector<32>(enumerate(Q));
// Scan all streams in the left hand side, looking for ones that are also
// in the right. Each time we find one, remove it. When we're done, Q
// should contain all the streams that are in the right but not in the left.
StreamPurposeProvider StreamProvider(28);
for (const auto &P : PI) {
typedef decltype(PI) ContainerType;
typedef typename ContainerType::value_type value_type;
auto Iter = llvm::find_if(QI, [P, &StreamProvider](const value_type &V) {
DiffResult Result = StreamProvider.compare(P.value(), V.value());
return Result == DiffResult::EQUIVALENT ||
Result == DiffResult::IDENTICAL;
});
if (Iter == QI.end()) {
D.printExplicit(StreamProvider.format(P.value(), false),
DiffResult::DIFFERENT, P.index(), "(not present)");
continue;
}
D.print<EquivalentDiffProvider>(StreamProvider.format(P.value(), false),
P.index(), Iter->index());
QI.erase(Iter);
}
for (const auto &Q : QI) {
D.printExplicit(StreamProvider.format(Q.value(), true),
DiffResult::DIFFERENT, "(not present)", Q.index());
}
return Error::success();
}
Error DiffStyle::diffStringTable() {
DiffPrinter D(2, "String Table", 30, 20, opts::diff::PrintResultColumn,
opts::diff::PrintValueColumns, outs());
D.printExplicit("File", DiffResult::UNSPECIFIED,
truncateStringFront(File1.getFilePath(), 18),
truncateStringFront(File2.getFilePath(), 18));
auto ExpectedST1 = File1.getStringTable();
auto ExpectedST2 = File2.getStringTable();
bool Has1 = !!ExpectedST1;
bool Has2 = !!ExpectedST2;
std::string Count1 = Has1 ? llvm::utostr(ExpectedST1->getNameCount())
: "(string table not present)";
std::string Count2 = Has2 ? llvm::utostr(ExpectedST2->getNameCount())
: "(string table not present)";
D.print("Number of Strings", Count1, Count2);
if (!Has1 || !Has2) {
consumeError(ExpectedST1.takeError());
consumeError(ExpectedST2.takeError());
return Error::success();
}
auto &ST1 = *ExpectedST1;
auto &ST2 = *ExpectedST2;
D.print("Hash Version", ST1.getHashVersion(), ST2.getHashVersion());
D.print("Byte Size", ST1.getByteSize(), ST2.getByteSize());
D.print("Signature", ST1.getSignature(), ST2.getSignature());
// Both have a valid string table, dive in and compare individual strings.
auto IdList1 = ST1.name_ids();
auto IdList2 = ST2.name_ids();
StringSet<> LS;
StringSet<> RS;
uint32_t Empty1 = 0;
uint32_t Empty2 = 0;
for (auto ID : IdList1) {
auto S = ST1.getStringForID(ID);
if (!S)
return S.takeError();
if (S->empty())
++Empty1;
else
LS.insert(*S);
}
for (auto ID : IdList2) {
auto S = ST2.getStringForID(ID);
if (!S)
return S.takeError();
if (S->empty())
++Empty2;
else
RS.insert(*S);
}
D.print("Empty Strings", Empty1, Empty2);
for (const auto &S : LS) {
auto R = RS.find(S.getKey());
std::string Truncated = truncateStringMiddle(S.getKey(), 28);
uint32_t I = cantFail(ST1.getIDForString(S.getKey()));
if (R == RS.end()) {
D.printExplicit(Truncated, DiffResult::DIFFERENT, I, "(not present)");
continue;
}
uint32_t J = cantFail(ST2.getIDForString(R->getKey()));
D.print<EquivalentDiffProvider>(Truncated, I, J);
RS.erase(R);
}
for (const auto &S : RS) {
auto L = LS.find(S.getKey());
std::string Truncated = truncateStringMiddle(S.getKey(), 28);
uint32_t J = cantFail(ST2.getIDForString(S.getKey()));
if (L == LS.end()) {
D.printExplicit(Truncated, DiffResult::DIFFERENT, "(not present)", J);
continue;
}
uint32_t I = cantFail(ST1.getIDForString(L->getKey()));
D.print<EquivalentDiffProvider>(Truncated, I, J);
}
return Error::success();
}
Error DiffStyle::diffFreePageMap() { return Error::success(); }
Error DiffStyle::diffInfoStream() {
DiffPrinter D(2, "PDB Stream", 22, 40, opts::diff::PrintResultColumn,
opts::diff::PrintValueColumns, outs());
D.printExplicit("File", DiffResult::UNSPECIFIED,
truncateStringFront(File1.getFilePath(), 38),
truncateStringFront(File2.getFilePath(), 38));
auto ExpectedInfo1 = File1.getPDBInfoStream();
auto ExpectedInfo2 = File2.getPDBInfoStream();
bool Has1 = !!ExpectedInfo1;
bool Has2 = !!ExpectedInfo2;
if (!(Has1 && Has2)) {
std::string L = Has1 ? "(present)" : "(not present)";
std::string R = Has2 ? "(present)" : "(not present)";
D.print("Stream", L, R);
consumeError(ExpectedInfo1.takeError());
consumeError(ExpectedInfo2.takeError());
return Error::success();
}
auto &IS1 = *ExpectedInfo1;
auto &IS2 = *ExpectedInfo2;
D.print("Stream Size", IS1.getStreamSize(), IS2.getStreamSize());
D.print("Age", IS1.getAge(), IS2.getAge());
D.print("Guid", IS1.getGuid(), IS2.getGuid());
D.print("Signature", IS1.getSignature(), IS2.getSignature());
D.print("Version", IS1.getVersion(), IS2.getVersion());
D.diffUnorderedArray("Feature", IS1.getFeatureSignatures(),
IS2.getFeatureSignatures());
D.print("Named Stream Size", IS1.getNamedStreamMapByteSize(),
IS2.getNamedStreamMapByteSize());
StringMap<uint32_t> NSL = IS1.getNamedStreams().getStringMap();
StringMap<uint32_t> NSR = IS2.getNamedStreams().getStringMap();
D.diffUnorderedMap<EquivalentDiffProvider>("Named Stream", NSL, NSR);
return Error::success();
}
typedef std::pair<uint32_t, DbiModuleDescriptor> IndexedModuleDescriptor;
typedef std::vector<IndexedModuleDescriptor> IndexedModuleDescriptorList;
static IndexedModuleDescriptorList
getModuleDescriptors(const DbiModuleList &ML) {
IndexedModuleDescriptorList List;
List.reserve(ML.getModuleCount());
for (uint32_t I = 0; I < ML.getModuleCount(); ++I)
List.emplace_back(I, ML.getModuleDescriptor(I));
return List;
}
static IndexedModuleDescriptorList::iterator
findOverrideEquivalentModule(uint32_t Modi,
IndexedModuleDescriptorList &OtherList) {
auto &EqMap = opts::diff::Equivalences;
auto Iter = EqMap.find(Modi);
if (Iter == EqMap.end())
return OtherList.end();
uint32_t EqValue = Iter->second;
return llvm::find_if(OtherList,
[EqValue](const IndexedModuleDescriptor &Desc) {
return Desc.first == EqValue;
});
}
static IndexedModuleDescriptorList::iterator
findEquivalentModule(const IndexedModuleDescriptor &Item,
IndexedModuleDescriptorList &OtherList, bool ItemIsRight) {
if (!ItemIsRight) {
uint32_t Modi = Item.first;
auto OverrideIter = findOverrideEquivalentModule(Modi, OtherList);
if (OverrideIter != OtherList.end())
return OverrideIter;
}
BinaryPathProvider PathProvider(28);
auto Iter = OtherList.begin();
auto End = OtherList.end();
for (; Iter != End; ++Iter) {
const IndexedModuleDescriptor *Left = &Item;
const IndexedModuleDescriptor *Right = &*Iter;
if (ItemIsRight)
std::swap(Left, Right);
DiffResult Result = PathProvider.compare(Left->second.getModuleName(),
Right->second.getModuleName());
if (Result == DiffResult::EQUIVALENT || Result == DiffResult::IDENTICAL)
return Iter;
}
return OtherList.end();
}
static void diffOneModule(DiffPrinter &D, const IndexedModuleDescriptor &Item,
IndexedModuleDescriptorList &Other,
bool ItemIsRight) {
StreamPurposeProvider HeaderProvider(70);
StreamInfo Info = StreamInfo::createModuleStream(
Item.second.getModuleName(), Item.second.getModuleStreamIndex(),
Item.first);
D.printFullRow(HeaderProvider.format(Info, ItemIsRight));
const auto *L = &Item;
auto Iter = findEquivalentModule(Item, Other, ItemIsRight);
if (Iter == Other.end()) {
// We didn't find this module at all on the other side. Just print one row
// and continue.
if (ItemIsRight)
D.print<ModiProvider>("- Modi", None, Item.first);
else
D.print<ModiProvider>("- Modi", Item.first, None);
return;
}
// We did find this module. Go through and compare each field.
const auto *R = &*Iter;
if (ItemIsRight)
std::swap(L, R);
BinaryPathProvider PathProvider(28);
D.print<ModiProvider>("- Modi", L->first, R->first);
D.print<BinaryPathProvider>("- Obj File Name", L->second.getObjFileName(),
R->second.getObjFileName(), PathProvider);
D.print<StreamNumberProvider>("- Debug Stream",
L->second.getModuleStreamIndex(),
R->second.getModuleStreamIndex());
D.print("- C11 Byte Size", L->second.getC11LineInfoByteSize(),
R->second.getC11LineInfoByteSize());
D.print("- C13 Byte Size", L->second.getC13LineInfoByteSize(),
R->second.getC13LineInfoByteSize());
D.print("- # of files", L->second.getNumberOfFiles(),
R->second.getNumberOfFiles());
D.print("- Pdb File Path Index", L->second.getPdbFilePathNameIndex(),
R->second.getPdbFilePathNameIndex());
D.print("- Source File Name Index", L->second.getSourceFileNameIndex(),
R->second.getSourceFileNameIndex());
D.print("- Symbol Byte Size", L->second.getSymbolDebugInfoByteSize(),
R->second.getSymbolDebugInfoByteSize());
Other.erase(Iter);
}
Error DiffStyle::diffDbiStream() {
DiffPrinter D(2, "DBI Stream", 40, 30, opts::diff::PrintResultColumn,
opts::diff::PrintValueColumns, outs());
D.printExplicit("File", DiffResult::UNSPECIFIED,
truncateStringFront(File1.getFilePath(), 28),
truncateStringFront(File2.getFilePath(), 28));
auto ExpectedDbi1 = File1.getPDBDbiStream();
auto ExpectedDbi2 = File2.getPDBDbiStream();
bool Has1 = !!ExpectedDbi1;
bool Has2 = !!ExpectedDbi2;
if (!(Has1 && Has2)) {
std::string L = Has1 ? "(present)" : "(not present)";
std::string R = Has2 ? "(present)" : "(not present)";
D.print("Stream", L, R);
consumeError(ExpectedDbi1.takeError());
consumeError(ExpectedDbi2.takeError());
return Error::success();
}
auto &DL = *ExpectedDbi1;
auto &DR = *ExpectedDbi2;
D.print("Dbi Version", (uint32_t)DL.getDbiVersion(),
(uint32_t)DR.getDbiVersion());
D.print("Age", DL.getAge(), DR.getAge());
D.print("Machine", (uint16_t)DL.getMachineType(),
(uint16_t)DR.getMachineType());
D.print("Flags", DL.getFlags(), DR.getFlags());
D.print("Build Major", DL.getBuildMajorVersion(), DR.getBuildMajorVersion());
D.print("Build Minor", DL.getBuildMinorVersion(), DR.getBuildMinorVersion());
D.print("Build Number", DL.getBuildNumber(), DR.getBuildNumber());
D.print("PDB DLL Version", DL.getPdbDllVersion(), DR.getPdbDllVersion());
D.print("PDB DLL RBLD", DL.getPdbDllRbld(), DR.getPdbDllRbld());
D.print<StreamNumberProvider>("DBG (FPO)",
DL.getDebugStreamIndex(DbgHeaderType::FPO),
DR.getDebugStreamIndex(DbgHeaderType::FPO));
D.print<StreamNumberProvider>(
"DBG (Exception)", DL.getDebugStreamIndex(DbgHeaderType::Exception),
DR.getDebugStreamIndex(DbgHeaderType::Exception));
D.print<StreamNumberProvider>("DBG (Fixup)",
DL.getDebugStreamIndex(DbgHeaderType::Fixup),
DR.getDebugStreamIndex(DbgHeaderType::Fixup));
D.print<StreamNumberProvider>(
"DBG (OmapToSrc)", DL.getDebugStreamIndex(DbgHeaderType::OmapToSrc),
DR.getDebugStreamIndex(DbgHeaderType::OmapToSrc));
D.print<StreamNumberProvider>(
"DBG (OmapFromSrc)", DL.getDebugStreamIndex(DbgHeaderType::OmapFromSrc),
DR.getDebugStreamIndex(DbgHeaderType::OmapFromSrc));
D.print<StreamNumberProvider>(
"DBG (SectionHdr)", DL.getDebugStreamIndex(DbgHeaderType::SectionHdr),
DR.getDebugStreamIndex(DbgHeaderType::SectionHdr));
D.print<StreamNumberProvider>(
"DBG (TokenRidMap)", DL.getDebugStreamIndex(DbgHeaderType::TokenRidMap),
DR.getDebugStreamIndex(DbgHeaderType::TokenRidMap));
D.print<StreamNumberProvider>("DBG (Xdata)",
DL.getDebugStreamIndex(DbgHeaderType::Xdata),
DR.getDebugStreamIndex(DbgHeaderType::Xdata));
D.print<StreamNumberProvider>("DBG (Pdata)",
DL.getDebugStreamIndex(DbgHeaderType::Pdata),
DR.getDebugStreamIndex(DbgHeaderType::Pdata));
D.print<StreamNumberProvider>("DBG (NewFPO)",
DL.getDebugStreamIndex(DbgHeaderType::NewFPO),
DR.getDebugStreamIndex(DbgHeaderType::NewFPO));
D.print<StreamNumberProvider>(
"DBG (SectionHdrOrig)",
DL.getDebugStreamIndex(DbgHeaderType::SectionHdrOrig),
DR.getDebugStreamIndex(DbgHeaderType::SectionHdrOrig));
D.print<StreamNumberProvider>("Globals Stream",
DL.getGlobalSymbolStreamIndex(),
DR.getGlobalSymbolStreamIndex());
D.print<StreamNumberProvider>("Publics Stream",
DL.getPublicSymbolStreamIndex(),
DR.getPublicSymbolStreamIndex());
D.print<StreamNumberProvider>("Symbol Records", DL.getSymRecordStreamIndex(),
DR.getSymRecordStreamIndex());
D.print("Has CTypes", DL.hasCTypes(), DR.hasCTypes());
D.print("Is Incrementally Linked", DL.isIncrementallyLinked(),
DR.isIncrementallyLinked());
D.print("Is Stripped", DL.isStripped(), DR.isStripped());
const DbiModuleList &ML = DL.modules();
const DbiModuleList &MR = DR.modules();
D.print("Module Count", ML.getModuleCount(), MR.getModuleCount());
D.print("Source File Count", ML.getSourceFileCount(),
MR.getSourceFileCount());
auto MDL = getModuleDescriptors(ML);
auto MDR = getModuleDescriptors(MR);
// Scan all module descriptors from the left, and look for corresponding
// module descriptors on the right.
for (const auto &L : MDL)
diffOneModule(D, L, MDR, false);
for (const auto &R : MDR)
diffOneModule(D, R, MDL, true);
return Error::success();
}
Error DiffStyle::diffSectionContribs() { return Error::success(); }
Error DiffStyle::diffSectionMap() { return Error::success(); }
Error DiffStyle::diffFpoStream() { return Error::success(); }
Error DiffStyle::diffTpiStream(int Index) { return Error::success(); }
Error DiffStyle::diffModuleInfoStream(int Index) { return Error::success(); }
Error DiffStyle::diffPublics() { return Error::success(); }
Error DiffStyle::diffGlobals() { return Error::success(); }