Index: lld/COFF/DriverUtils.cpp
===================================================================
--- lld/COFF/DriverUtils.cpp
+++ lld/COFF/DriverUtils.cpp
@@ -76,8 +76,7 @@
 
 // Parses a string in the form of "<integer>[,<integer>]".
 void parseNumbers(StringRef arg, uint64_t *addr, uint64_t *size) {
-  StringRef s1, s2;
-  std::tie(s1, s2) = arg.split(',');
+  auto [s1, s2] = arg.split(',');
   if (s1.getAsInteger(0, *addr))
     fatal("invalid number: " + s1);
   if (size && !s2.empty() && s2.getAsInteger(0, *size))
@@ -87,8 +86,7 @@
 // Parses a string in the form of "<integer>[.<integer>]".
 // If second number is not present, Minor is set to 0.
 void parseVersion(StringRef arg, uint32_t *major, uint32_t *minor) {
-  StringRef s1, s2;
-  std::tie(s1, s2) = arg.split('.');
+  auto [s1, s2] = arg.split('.');
   if (s1.getAsInteger(10, *major))
     fatal("invalid number: " + s1);
   *minor = 0;
@@ -120,8 +118,7 @@
 // Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
 void parseSubsystem(StringRef arg, WindowsSubsystem *sys, uint32_t *major,
                     uint32_t *minor, bool *gotVersion) {
-  StringRef sysStr, ver;
-  std::tie(sysStr, ver) = arg.split(',');
+  auto [sysStr, ver] = arg.split(',');
   std::string sysStrLower = sysStr.lower();
   *sys = StringSwitch<WindowsSubsystem>(sysStrLower)
     .Case("boot_application", IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION)
@@ -146,8 +143,7 @@
 // Parse a string of the form of "<from>=<to>".
 // Results are directly written to Config.
 void parseAlternateName(StringRef s) {
-  StringRef from, to;
-  std::tie(from, to) = s.split('=');
+  auto [from, to] = s.split('=');
   if (from.empty() || to.empty())
     fatal("/alternatename: invalid argument: " + s);
   auto it = config->alternateNames.find(from);
@@ -159,8 +155,7 @@
 // Parse a string of the form of "<from>=<to>".
 // Results are directly written to Config.
 void parseMerge(StringRef s) {
-  StringRef from, to;
-  std::tie(from, to) = s.split('=');
+  auto [from, to] = s.split('=');
   if (from.empty() || to.empty())
     fatal("/merge: invalid argument: " + s);
   if (from == ".rsrc" || to == ".rsrc")
@@ -224,8 +219,7 @@
 
 // Parses /section option argument.
 void parseSection(StringRef s) {
-  StringRef name, attrs;
-  std::tie(name, attrs) = s.split(',');
+  auto [name, attrs] = s.split(',');
   if (name.empty() || attrs.empty())
     fatal("/section: invalid argument: " + s);
   config->section[name] = parseSectionAttributes(attrs);
@@ -233,8 +227,7 @@
 
 // Parses /aligncomm option argument.
 void parseAligncomm(StringRef s) {
-  StringRef name, align;
-  std::tie(name, align) = s.split(',');
+  auto [name, align] = s.split(',');
   if (name.empty() || align.empty()) {
     error("/aligncomm: invalid argument: " + s);
     return;
@@ -318,8 +311,7 @@
 // Results are directly written to Config.
 void parseSwaprun(StringRef arg) {
   do {
-    StringRef swaprun, newArg;
-    std::tie(swaprun, newArg) = arg.split(',');
+    auto [swaprun, newArg] = arg.split(',');
     if (swaprun.equals_insensitive("cd"))
       config->swaprunCD = true;
     else if (swaprun.equals_insensitive("net"))
@@ -561,8 +553,7 @@
     goto err;
 
   if (e.name.contains('=')) {
-    StringRef x, y;
-    std::tie(x, y) = e.name.split("=");
+    auto [x, y] = e.name.split("=");
 
     // If "<name>=<dllname>.<name>".
     if (y.contains(".")) {
@@ -716,8 +707,7 @@
 // Parses a string in the form of "key=value" and check
 // if value matches previous values for the same key.
 void checkFailIfMismatch(StringRef arg, InputFile *source) {
-  StringRef k, v;
-  std::tie(k, v) = arg.split('=');
+  auto [k, v] = arg.split('=');
   if (k.empty() || v.empty())
     fatal("/failifmismatch: invalid argument: " + arg);
   std::pair<StringRef, InputFile *> existing = config->mustMatch[k];
Index: lld/COFF/SymbolTable.cpp
===================================================================
--- lld/COFF/SymbolTable.cpp
+++ lld/COFF/SymbolTable.cpp
@@ -245,9 +245,7 @@
   const size_t maxUndefReferences = 3;
   size_t numDisplayedRefs = 0, numRefs = 0;
   for (const UndefinedDiag::File &ref : undefDiag.files) {
-    std::vector<std::string> symbolLocations;
-    size_t totalLocations = 0;
-    std::tie(symbolLocations, totalLocations) = getSymbolLocations(
+    auto [symbolLocations, totalLocations] = getSymbolLocations(
         ref.file, ref.symIndex, maxUndefReferences - numDisplayedRefs);
 
     numRefs += totalLocations;
@@ -543,9 +541,7 @@
 
 Symbol *SymbolTable::addUndefined(StringRef name, InputFile *f,
                                   bool isWeakAlias) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(name, f);
+  auto [s, wasInserted] = insert(name, f);
   if (wasInserted || (s->isLazy() && isWeakAlias)) {
     replaceSymbol<Undefined>(s, name);
     return s;
@@ -557,9 +553,7 @@
 
 void SymbolTable::addLazyArchive(ArchiveFile *f, const Archive::Symbol &sym) {
   StringRef name = sym.getName();
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(name);
+  auto [s, wasInserted] = insert(name);
   if (wasInserted) {
     replaceSymbol<LazyArchive>(s, f, sym);
     return;
@@ -573,9 +567,7 @@
 
 void SymbolTable::addLazyObject(InputFile *f, StringRef n) {
   assert(f->lazy);
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, f);
+  auto [s, wasInserted] = insert(n, f);
   if (wasInserted) {
     replaceSymbol<LazyObject>(s, f, n);
     return;
@@ -590,9 +582,7 @@
 
 void SymbolTable::addLazyDLLSymbol(DLLFile *f, DLLFile::Symbol *sym,
                                    StringRef n) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n);
+  auto [s, wasInserted] = insert(n);
   if (wasInserted) {
     replaceSymbol<LazyDLLSymbol>(s, f, sym, n);
     return;
@@ -672,9 +662,7 @@
 }
 
 Symbol *SymbolTable::addAbsolute(StringRef n, COFFSymbolRef sym) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, nullptr);
+  auto [s, wasInserted] = insert(n, nullptr);
   s->isUsedInRegularObj = true;
   if (wasInserted || isa<Undefined>(s) || s->isLazy())
     replaceSymbol<DefinedAbsolute>(s, n, sym);
@@ -687,9 +675,7 @@
 }
 
 Symbol *SymbolTable::addAbsolute(StringRef n, uint64_t va) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, nullptr);
+  auto [s, wasInserted] = insert(n, nullptr);
   s->isUsedInRegularObj = true;
   if (wasInserted || isa<Undefined>(s) || s->isLazy())
     replaceSymbol<DefinedAbsolute>(s, n, va);
@@ -702,9 +688,7 @@
 }
 
 Symbol *SymbolTable::addSynthetic(StringRef n, Chunk *c) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, nullptr);
+  auto [s, wasInserted] = insert(n, nullptr);
   s->isUsedInRegularObj = true;
   if (wasInserted || isa<Undefined>(s) || s->isLazy())
     replaceSymbol<DefinedSynthetic>(s, n, c);
@@ -716,9 +700,7 @@
 Symbol *SymbolTable::addRegular(InputFile *f, StringRef n,
                                 const coff_symbol_generic *sym, SectionChunk *c,
                                 uint32_t sectionOffset) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, f);
+  auto [s, wasInserted] = insert(n, f);
   if (wasInserted || !isa<DefinedRegular>(s))
     replaceSymbol<DefinedRegular>(s, f, n, /*IsCOMDAT*/ false,
                                   /*IsExternal*/ true, sym, c);
@@ -730,9 +712,7 @@
 std::pair<DefinedRegular *, bool>
 SymbolTable::addComdat(InputFile *f, StringRef n,
                        const coff_symbol_generic *sym) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, f);
+  auto [s, wasInserted] = insert(n, f);
   if (wasInserted || !isa<DefinedRegular>(s)) {
     replaceSymbol<DefinedRegular>(s, f, n, /*IsCOMDAT*/ true,
                                   /*IsExternal*/ true, sym, nullptr);
@@ -746,9 +726,7 @@
 
 Symbol *SymbolTable::addCommon(InputFile *f, StringRef n, uint64_t size,
                                const coff_symbol_generic *sym, CommonChunk *c) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, f);
+  auto [s, wasInserted] = insert(n, f);
   if (wasInserted || !isa<DefinedCOFF>(s))
     replaceSymbol<DefinedCommon>(s, f, n, size, sym, c);
   else if (auto *dc = dyn_cast<DefinedCommon>(s))
@@ -758,9 +736,7 @@
 }
 
 Symbol *SymbolTable::addImportData(StringRef n, ImportFile *f) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(n, nullptr);
+  auto [s, wasInserted] = insert(n, nullptr);
   s->isUsedInRegularObj = true;
   if (wasInserted || isa<Undefined>(s) || s->isLazy()) {
     replaceSymbol<DefinedImportData>(s, n, f);
@@ -773,9 +749,7 @@
 
 Symbol *SymbolTable::addImportThunk(StringRef name, DefinedImportData *id,
                                     uint16_t machine) {
-  Symbol *s;
-  bool wasInserted;
-  std::tie(s, wasInserted) = insert(name, nullptr);
+  auto [s, wasInserted] = insert(name, nullptr);
   s->isUsedInRegularObj = true;
   if (wasInserted || isa<Undefined>(s) || s->isLazy()) {
     replaceSymbol<DefinedImportThunk>(s, name, id, machine);
Index: lld/COFF/Writer.cpp
===================================================================
--- lld/COFF/Writer.cpp
+++ lld/COFF/Writer.cpp
@@ -451,11 +451,8 @@
       if (isInRange(rel.Type, s, p, margin))
         continue;
 
-      // If the target isn't in range, hook it up to an existing or new
-      // thunk.
-      Defined *thunk;
-      bool wasNew;
-      std::tie(thunk, wasNew) = getThunk(lastThunks, sym, p, rel.Type, margin);
+      // If the target isn't in range, hook it up to an existing or new thunk.
+      auto [thunk, wasNew] = getThunk(lastThunks, sym, p, rel.Type, margin);
       if (wasNew) {
         Chunk *thunkChunk = thunk->getChunk();
         thunkChunk->setRVA(