Remove redundant string initialization (NFC)

Identified with readability-redundant-string-init.

Author: kazutakahirata

clang-tools-extra/clang-tidy/cert/LimitedRandomnessCheck.cpp

@@ -24,7 +24,7 @@ void LimitedRandomnessCheck::registerMatchers(MatchFinder *Finder) {
 }
 
 void LimitedRandomnessCheck::check(const MatchFinder::MatchResult &Result) {
-  std::string Msg = "";
+  std::string Msg;
   if (getLangOpts().CPlusPlus)
     Msg = "; use C++11 random library instead";
 

clang/lib/Basic/Targets/M68k.cpp

@@ -29,7 +29,7 @@ M68kTargetInfo::M68kTargetInfo(const llvm::Triple &Triple,
                                const TargetOptions &)
     : TargetInfo(Triple) {
 
-  std::string Layout = "";
+  std::string Layout;
 
   // M68k is Big Endian
   Layout += "E";

clang/lib/Basic/Targets/PPC.h

@@ -414,7 +414,7 @@ class LLVM_LIBRARY_VISIBILITY PPC64TargetInfo : public PPCTargetInfo {
     LongWidth = LongAlign = PointerWidth = PointerAlign = 64;
     IntMaxType = SignedLong;
     Int64Type = SignedLong;
-    std::string DataLayout = "";
+    std::string DataLayout;
 
     if (Triple.isOSAIX()) {
       // TODO: Set appropriate ABI for AIX platform.

clang/lib/CodeGen/CGOpenMPRuntime.cpp

@@ -1434,7 +1434,7 @@ llvm::Value *CGOpenMPRuntime::emitUpdateLocation(CodeGenFunction &CGF,
       Loc.isInvalid()) {
     SrcLocStr = OMPBuilder.getOrCreateDefaultSrcLocStr();
   } else {
-    std::string FunctionName = "";
+    std::string FunctionName;
     if (const auto *FD = dyn_cast_or_null<FunctionDecl>(CGF.CurFuncDecl))
       FunctionName = FD->getQualifiedNameAsString();
     PresumedLoc PLoc = CGF.getContext().getSourceManager().getPresumedLoc(Loc);
@@ -9540,7 +9540,7 @@ emitMappingInformation(CodeGenFunction &CGF, llvm::OpenMPIRBuilder &OMPBuilder,
     Loc = MapExprs.getMapDecl()->getLocation();
   }
 
-  std::string ExprName = "";
+  std::string ExprName;
   if (MapExprs.getMapExpr()) {
     PrintingPolicy P(CGF.getContext().getLangOpts());
     llvm::raw_string_ostream OS(ExprName);

clang/lib/Format/NamespaceEndCommentsFixer.cpp

@@ -28,7 +28,7 @@ std::string computeName(const FormatToken *NamespaceTok) {
   assert(NamespaceTok &&
          NamespaceTok->isOneOf(tok::kw_namespace, TT_NamespaceMacro) &&
          "expecting a namespace token");
-  std::string name = "";
+  std::string name;
   const FormatToken *Tok = NamespaceTok->getNextNonComment();
   if (NamespaceTok->is(TT_NamespaceMacro)) {
     // Collects all the non-comment tokens between opening parenthesis
@@ -224,7 +224,7 @@ std::pair<tooling::Replacements, unsigned> NamespaceEndCommentsFixer::analyze(
     return {Fixes, 0};
   }
 
-  std::string AllNamespaceNames = "";
+  std::string AllNamespaceNames;
   size_t StartLineIndex = SIZE_MAX;
   StringRef NamespaceTokenText;
   unsigned int CompactedNamespacesCount = 0;

clang/lib/Frontend/InitHeaderSearch.cpp

@@ -354,7 +354,7 @@ void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
     break;
   case llvm::Triple::PS4: {
     // <isysroot> gets prepended later in AddPath().
-    std::string BaseSDKPath = "";
+    std::string BaseSDKPath;
     if (!HasSysroot) {
       const char *envValue = getenv("SCE_ORBIS_SDK_DIR");
       if (envValue)

clang/lib/StaticAnalyzer/Checkers/ReturnValueChecker.cpp

@@ -59,7 +59,7 @@ class ReturnValueChecker : public Checker<check::PostCall, check::EndFunction> {
 } // namespace
 
 static std::string getName(const CallEvent &Call) {
-  std::string Name = "";
+  std::string Name;
   if (const auto *MD = dyn_cast<CXXMethodDecl>(Call.getDecl()))
     if (const CXXRecordDecl *RD = MD->getParent())
       Name += RD->getNameAsString() + "::";

clang/tools/clang-scan-deps/ClangScanDeps.cpp

@@ -470,7 +470,7 @@ int main(int argc, const char **argv) {
   AdjustingCompilations->appendArgumentsAdjuster(
       [&ResourceDirCache](const tooling::CommandLineArguments &Args,
                           StringRef FileName) {
-        std::string LastO = "";
+        std::string LastO;
         bool HasResourceDir = false;
         bool ClangCLMode = false;
         auto FlagsEnd = llvm::find(Args, "--");

clang/utils/TableGen/NeonEmitter.cpp

@@ -1473,7 +1473,7 @@ Intrinsic::DagEmitter::emitDagCall(DagInit *DI, bool MatchMangledName) {
   Intr.Dependencies.insert(&Callee);
 
   // Now create the call itself.
-  std::string S = "";
+  std::string S;
   if (!Callee.isBigEndianSafe())
     S += CallPrefix.str();
   S += Callee.getMangledName(true) + "(";

lldb/source/Commands/CommandCompletions.cpp

@@ -600,7 +600,7 @@ void CommandCompletions::VariablePath(CommandInterpreter &interpreter,
 void CommandCompletions::Registers(CommandInterpreter &interpreter,
                                    CompletionRequest &request,
                                    SearchFilter *searcher) {
-  std::string reg_prefix = "";
+  std::string reg_prefix;
   if (request.GetCursorArgumentPrefix().startswith("$"))
     reg_prefix = "$";
 

lldb/source/Plugins/Disassembler/LLVMC/DisassemblerLLVMC.cpp

@@ -1111,7 +1111,7 @@ DisassemblerLLVMC::DisassemblerLLVMC(const ArchSpec &arch,
       triple.getSubArch() == llvm::Triple::NoSubArch)
     triple.setArchName("armv8.7a");
 
-  std::string features_str = "";
+  std::string features_str;
   const char *triple_str = triple.getTriple().c_str();
 
   // ARM Cortex M0-M7 devices only execute thumb instructions

lldb/source/Plugins/Instruction/MIPS/EmulateInstructionMIPS.cpp

@@ -137,7 +137,7 @@ EmulateInstructionMIPS::EmulateInstructionMIPS(
     break;
   }
 
-  std::string features = "";
+  std::string features;
   uint32_t arch_flags = arch.GetFlags();
   if (arch_flags & ArchSpec::eMIPSAse_msa)
     features += "+msa,";

lldb/source/Plugins/Instruction/MIPS64/EmulateInstructionMIPS64.cpp

@@ -137,7 +137,7 @@ EmulateInstructionMIPS64::EmulateInstructionMIPS64(
     break;
   }
 
-  std::string features = "";
+  std::string features;
   uint32_t arch_flags = arch.GetFlags();
   if (arch_flags & ArchSpec::eMIPSAse_msa)
     features += "+msa,";

lldb/source/Plugins/InstrumentationRuntime/MainThreadChecker/InstrumentationRuntimeMainThreadChecker.cpp

@@ -100,14 +100,14 @@ InstrumentationRuntimeMainThreadChecker::RetrieveReportData(
   if (!apiname_ptr)
     return StructuredData::ObjectSP();
 
-  std::string apiName = "";
+  std::string apiName;
   Status read_error;
   target.ReadCStringFromMemory(apiname_ptr, apiName, read_error);
   if (read_error.Fail())
     return StructuredData::ObjectSP();
 
-  std::string className = "";
-  std::string selector = "";
+  std::string className;
+  std::string selector;
   if (apiName.substr(0, 2) == "-[") {
     size_t spacePos = apiName.find(' ');
     if (spacePos != std::string::npos) {

lldb/source/Plugins/InstrumentationRuntime/TSan/InstrumentationRuntimeTSan.cpp

@@ -711,7 +711,7 @@ addr_t InstrumentationRuntimeTSan::GetMainRacyAddress(
 std::string InstrumentationRuntimeTSan::GetLocationDescription(
     StructuredData::ObjectSP report, addr_t &global_addr,
     std::string &global_name, std::string &filename, uint32_t &line) {
-  std::string result = "";
+  std::string result;
 
   ProcessSP process_sp = GetProcessSP();
 
@@ -820,8 +820,8 @@ bool InstrumentationRuntimeTSan::NotifyBreakpointHit(
     report->GetAsDictionary()->AddIntegerItem("memory_address", main_address);
 
     addr_t global_addr = 0;
-    std::string global_name = "";
-    std::string location_filename = "";
+    std::string global_name;
+    std::string location_filename;
     uint32_t location_line = 0;
     std::string location_description = instance->GetLocationDescription(
         report, global_addr, global_name, location_filename, location_line);

lldb/source/Plugins/ObjectFile/Minidump/MinidumpFileBuilder.cpp

@@ -115,7 +115,7 @@ Status MinidumpFileBuilder::AddSystemInfo(const llvm::Triple &target_triple) {
   sys_info.PlatformId = platform_id;
   m_data.AppendData(&sys_info, sizeof(llvm::minidump::SystemInfo));
 
-  std::string csd_string = "";
+  std::string csd_string;
 
   error = WriteString(csd_string, &m_data);
   if (error.Fail()) {

lldb/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.cpp

@@ -693,7 +693,7 @@ const UnixSignalsSP &PlatformRemoteGDBServer::GetRemoteUnixSignals() {
         if (object_sp && object_sp->IsValid())
           notify = object_sp->GetBooleanValue();
 
-        std::string description{""};
+        std::string description;
         object_sp = dict->GetValueForKey("description");
         if (object_sp && object_sp->IsValid())
           description = std::string(object_sp->GetStringValue());

lldb/source/Target/RegisterContextUnwind.cpp

@@ -1509,7 +1509,7 @@ RegisterContextUnwind::SavedLocationForRegister(
                    regnum.GetName(), regnum.GetAsKind(eRegisterKindLLDB));
       return UnwindLLDB::RegisterSearchResult::eRegisterFound;
     } else {
-      std::string unwindplan_name("");
+      std::string unwindplan_name;
       if (m_full_unwind_plan_sp) {
         unwindplan_name += "via '";
         unwindplan_name += m_full_unwind_plan_sp->GetSourceName().AsCString();

llvm/lib/DebugInfo/DWARF/DWARFDebugAbbrev.cpp

@@ -74,7 +74,7 @@ std::string DWARFAbbreviationDeclarationSet::getCodeRange() const {
   for (const auto &Decl : Decls)
     Codes.push_back(Decl.getCode());
 
-  std::string Buffer = "";
+  std::string Buffer;
   raw_string_ostream Stream(Buffer);
   // Each iteration through this loop represents a single contiguous range in
   // the set of codes.

llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp

@@ -410,7 +410,7 @@ void AMDGPUTargetID::setTargetIDFromTargetIDStream(StringRef TargetID) {
 }
 
 std::string AMDGPUTargetID::toString() const {
-  std::string StringRep = "";
+  std::string StringRep;
   raw_string_ostream StreamRep(StringRep);
 
   auto TargetTriple = STI.getTargetTriple();
@@ -421,7 +421,7 @@ std::string AMDGPUTargetID::toString() const {
             << TargetTriple.getOSName() << '-'
             << TargetTriple.getEnvironmentName() << '-';
 
-  std::string Processor = "";
+  std::string Processor;
   // TODO: Following else statement is present here because we used various
   // alias names for GPUs up until GFX9 (e.g. 'fiji' is same as 'gfx803').
   // Remove once all aliases are removed from GCNProcessors.td.
@@ -432,7 +432,7 @@ std::string AMDGPUTargetID::toString() const {
                  Twine(Version.Stepping))
                     .str();
 
-  std::string Features = "";
+  std::string Features;
   if (Optional<uint8_t> HsaAbiVersion = getHsaAbiVersion(&STI)) {
     switch (*HsaAbiVersion) {
     case ELF::ELFABIVERSION_AMDGPU_HSA_V2: