Clang Driver: refactor support for writing response files to be specified at Command creation, rather than as part of the Tool.

[jyknight]

Summary

This resolves the hack I just added to allow Darwin toolchain to vary
its level of support based on -mlinker-version=.

The change preserves the _current_ settings for response-file support.
Some tools look likely to be declaring that they don't support
response files, in error, however, I kept them as-is in order for this
change to be a simple refactoring.

[steven_wu]

LGTM.

clang/include/clang/Driver/Job.h

 
 #include "clang/Basic/LLVM.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/Option/Option.h"
+#include "llvm/Support/Program.h"
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
 
 namespace clang {
 namespace driver {
 
 class Action;
 class InputInfo;
 class Tool;
 
 struct CrashReportInfo {
   StringRef Filename;
   StringRef VFSPath;
 
   CrashReportInfo(StringRef Filename, StringRef VFSPath)
       : Filename(Filename), VFSPath(VFSPath) {}
 };
 
+// Encodes the kind of response file supported for a command invocation.
+// Response files are necessary if the command line gets too large, requiring
+// the arguments to be transferred to a file.
+struct ResponseFileSupport {
+  enum ResponseFileKind {
+    // Provides full support for response files, which means we can transfer
+    // all tool input arguments to a file.
+    RF_Full,
+    // Input file names can live in a file, but flags can't. This is a special
+    // case for old versions of Apple's ld64.
+    RF_FileList,
+    // Does not support response files: all arguments must be passed via
+    // command line.
+    RF_None
+  };
+  /// The level of support for response files.
+  ResponseFileKind ResponseKind;
+
+  /// The encoding to use when writing response files on Windows. Ignored on
+  /// other host OSes.
+  ///
+  /// Windows use cases: - GCC and Binutils on mingw only accept ANSI response
+  /// files encoded with the system current code page.
+  /// - MSVC's CL.exe and LINK.exe accept UTF16 on Windows.
+  /// - Clang accepts both UTF8 and UTF16.
+  ///
+  /// FIXME: When GNU tools learn how to parse UTF16 on Windows, we should
+  /// always use UTF16 for Windows, which is the Windows official encoding for
+  /// international characters.
+  llvm::sys::WindowsEncodingMethod ResponseEncoding;
+
+  /// What prefix to use for the command-line argument when passing a response
+  /// file.
+  const char *ResponseFlag;
+
+  /// Returns a ResponseFileSupport indicating that response files are not
+  /// supported.
+  static constexpr ResponseFileSupport None() {
+    return {RF_None, llvm::sys::WEM_UTF8, nullptr};
+  }
+
+  /// Returns a ResponseFileSupport indicating that response files are
+  /// supported, using the @file syntax. On windows, the file is written in the
+  /// UTF8 encoding. On other OSes, no re-encoding occurs.
+  static constexpr ResponseFileSupport AtFileUTF8() {
+    return {RF_Full, llvm::sys::WEM_UTF8, "@"};
+  }
+
+  /// Returns a ResponseFileSupport indicating that response files are
+  /// supported, using the @file syntax. On windows, the file is written in the
+  /// current ANSI code-page encoding. On other OSes, no re-encoding occurs.
+  static constexpr ResponseFileSupport AtFileCurCP() {
+    return {RF_Full, llvm::sys::WEM_CurrentCodePage, "@"};
+  }
+
+  /// Returns a ResponseFileSupport indicating that response files are
+  /// supported, using the @file syntax. On windows, the file is written in the
+  /// UTF-16 encoding. On other OSes, no re-encoding occurs.
+  static constexpr ResponseFileSupport AtFileUTF16() {
+    return {RF_Full, llvm::sys::WEM_UTF16, "@"};
+  }
+};
+
 /// Command - An executable path/name and argument vector to
 /// execute.
 class Command {
   /// Source - The action which caused the creation of this job.
   const Action &Source;
 
   /// Tool - The tool which caused the creation of this job.
   const Tool &Creator;
 
+  /// Whether and how to generate response files if the arguments are too long.
+  ResponseFileSupport ResponseSupport;
+
   /// The executable to run.
   const char *Executable;
 
   /// The list of program arguments (not including the implicit first
   /// argument, which will be the executable).
   llvm::opt::ArgStringList Arguments;
 
   /// The list of program arguments which are inputs.

 
 public:
   /// Whether to print the input filenames when executing.
   bool PrintInputFilenames = false;
 
   /// Whether the command will be executed in this process or not.
   bool InProcess = false;
 
-  Command(const Action &Source, const Tool &Creator, const char *Executable,
+  Command(const Action &Source, const Tool &Creator,
+          ResponseFileSupport ResponseSupport, const char *Executable,
           const llvm::opt::ArgStringList &Arguments,
           ArrayRef<InputInfo> Inputs);
   // FIXME: This really shouldn't be copyable, but is currently copied in some
   // error handling in Driver::generateCompilationDiagnostics.
   Command(const Command &) = default;
   virtual ~Command() = default;
 
   virtual void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,
                      CrashReportInfo *CrashInfo = nullptr) const;
 
   virtual int Execute(ArrayRef<Optional<StringRef>> Redirects,
                       std::string *ErrMsg, bool *ExecutionFailed) const;
 
   /// getSource - Return the Action which caused the creation of this job.
   const Action &getSource() const { return Source; }
 
   /// getCreator - Return the Tool which caused the creation of this job.
   const Tool &getCreator() const { return Creator; }
 
+  /// Returns the kind of response file supported by the current invocation.
+  const ResponseFileSupport &getResponseFileSupport() {
+    return ResponseSupport;
+  }
+
   /// Set to pass arguments via a response file when launching the command
   void setResponseFile(const char *FileName);
 
-  /// Set an input file list, necessary if we need to use a response file but
-  /// the tool being called only supports input files lists.
+  /// Set an input file list, necessary if you specified an RF_FileList response
+  /// file support.
   void setInputFileList(llvm::opt::ArgStringList List) {
     InputFileList = std::move(List);
   }
 
   /// Sets the environment to be used by the new process.
   /// \param NewEnvironment An array of environment variables.
   /// \remark If the environment remains unset, then the environment
   ///         from the parent process will be used.
   virtual void setEnvironment(llvm::ArrayRef<const char *> NewEnvironment);
 
   const char *getExecutable() const { return Executable; }
 
   const llvm::opt::ArgStringList &getArguments() const { return Arguments; }
 
 protected:
   /// Optionally print the filenames to be compiled
   void PrintFileNames() const;
 };
 
 /// Use the CC1 tool callback when available, to avoid creating a new process
 class CC1Command : public Command {
 public:
-  CC1Command(const Action &Source, const Tool &Creator, const char *Executable,
+  CC1Command(const Action &Source, const Tool &Creator,
+             ResponseFileSupport ResponseSupport, const char *Executable,
              const llvm::opt::ArgStringList &Arguments,
              ArrayRef<InputInfo> Inputs);
 
   void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,
              CrashReportInfo *CrashInfo = nullptr) const override;
 
   int Execute(ArrayRef<Optional<StringRef>> Redirects, std::string *ErrMsg,
               bool *ExecutionFailed) const override;
 
   void setEnvironment(llvm::ArrayRef<const char *> NewEnvironment) override;
 };
 
 /// Like Command, but with a fallback which is executed in case
 /// the primary command crashes.
 class FallbackCommand : public Command {
 public:
   FallbackCommand(const Action &Source_, const Tool &Creator_,
-                  const char *Executable_,
+                  ResponseFileSupport ResponseSupport, const char *Executable_,
                   const llvm::opt::ArgStringList &Arguments_,
                   ArrayRef<InputInfo> Inputs,
                   std::unique_ptr<Command> Fallback_);
 
   void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,
              CrashReportInfo *CrashInfo = nullptr) const override;
 
   int Execute(ArrayRef<Optional<StringRef>> Redirects, std::string *ErrMsg,
               bool *ExecutionFailed) const override;
 
 private:
   std::unique_ptr<Command> Fallback;
 };
 
 /// Like Command, but always pretends that the wrapped command succeeded.
 class ForceSuccessCommand : public Command {
 public:
   ForceSuccessCommand(const Action &Source_, const Tool &Creator_,
+                      ResponseFileSupport ResponseSupport,
                       const char *Executable_,
                       const llvm::opt::ArgStringList &Arguments_,
                       ArrayRef<InputInfo> Inputs);
 
   void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,
              CrashReportInfo *CrashInfo = nullptr) const override;
 
   int Execute(ArrayRef<Optional<StringRef>> Redirects, std::string *ErrMsg,

clang/include/clang/Driver/Tool.h

 //===--- Tool.h - Compilation Tools -----------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_DRIVER_TOOL_H
 #define LLVM_CLANG_DRIVER_TOOL_H
 
 #include "clang/Basic/LLVM.h"
-#include "llvm/Support/Program.h"
 
 namespace llvm {
 namespace opt {
   class ArgList;
 }
 }
 
 namespace clang {
 namespace driver {
 
   class Compilation;
   class InputInfo;
   class Job;
   class JobAction;
   class ToolChain;
 
   typedef SmallVector<InputInfo, 4> InputInfoList;
 
 /// Tool - Information on a specific compilation tool.
 class Tool {
-public:
-  // Documents the level of support for response files in this tool.
-  // Response files are necessary if the command line gets too large,
-  // requiring the arguments to be transferred to a file.
-  enum ResponseFileSupport {
-    // Provides full support for response files, which means we can transfer
-    // all tool input arguments to a file. E.g.: clang, gcc, binutils and MSVC
-    // tools.
-    RF_Full,
-    // Input file names can live in a file, but flags can't. E.g.: ld64 (Mac
-    // OS X linker).
-    RF_FileList,
-    // Does not support response files: all arguments must be passed via
-    // command line.
-    RF_None
-  };
-
-private:
   /// The tool name (for debugging).
   const char *Name;
 
   /// The human readable name for the tool, for use in diagnostics.
   const char *ShortName;
 
   /// The tool chain this tool is a part of.
   const ToolChain &TheToolChain;
 
-  /// The level of support for response files seen in this tool
-  const ResponseFileSupport ResponseSupport;
-
-  /// The encoding to use when writing response files for this tool on Windows
-  const llvm::sys::WindowsEncodingMethod ResponseEncoding;
-
-  /// The flag used to pass a response file via command line to this tool
-  const char *const ResponseFlag;
-
 public:
-  Tool(const char *Name, const char *ShortName, const ToolChain &TC,
-       ResponseFileSupport ResponseSupport = RF_None,
-       llvm::sys::WindowsEncodingMethod ResponseEncoding = llvm::sys::WEM_UTF8,
-       const char *ResponseFlag = "@");
+  Tool(const char *Name, const char *ShortName, const ToolChain &TC);
 
 public:
   virtual ~Tool();
 
   const char *getName() const { return Name; }
 
   const char *getShortName() const { return ShortName; }
 
   const ToolChain &getToolChain() const { return TheToolChain; }
 
   virtual bool hasIntegratedAssembler() const { return false; }
   virtual bool canEmitIR() const { return false; }
   virtual bool hasIntegratedCPP() const = 0;
   virtual bool isLinkJob() const { return false; }
   virtual bool isDsymutilJob() const { return false; }
-  /// Returns the level of support for response files of this tool,
-  /// whether it accepts arguments to be passed via a file on disk.
-  ResponseFileSupport getResponseFilesSupport() const {
-    return ResponseSupport;
-  }
-  /// Returns which encoding the response file should use. This is only
-  /// relevant on Windows platforms where there are different encodings being
-  /// accepted for different tools. On UNIX, UTF8 is universal.
-  ///
-  /// Windows use cases: - GCC and Binutils on mingw only accept ANSI response
-  /// files encoded with the system current code page.
-  /// - MSVC's CL.exe and LINK.exe accept UTF16 on Windows.
-  /// - Clang accepts both UTF8 and UTF16.
-  ///
-  /// FIXME: When GNU tools learn how to parse UTF16 on Windows, we should
-  /// always use UTF16 for Windows, which is the Windows official encoding for
-  /// international characters.
-  llvm::sys::WindowsEncodingMethod getResponseFileEncoding() const {
-    return ResponseEncoding;
-  }
-  /// Returns which prefix to use when passing the name of a response
-  /// file as a parameter to this tool.
-  const char *getResponseFileFlag() const { return ResponseFlag; }
 
   /// Does this tool have "good" standardized diagnostics, or should the
   /// driver add an additional "command failed" diagnostic on failures.
   virtual bool hasGoodDiagnostics() const { return false; }
 
   /// ConstructJob - Construct jobs to perform the action \p JA,
   /// writing to \p Output and with \p Inputs, and add the jobs to
   /// \p C.

clang/include/clang/Driver/ToolChain.h

static void addSystemIncludes(const llvm::opt::ArgList &DriverArgs,
                                 ArrayRef<StringRef> Paths);
   ///@}
 
 public:
   virtual ~ToolChain();
 
   // Accessors
 
-  /// Temporary for Darwin::Linker
-  const llvm::opt::ArgList &getArgs_DO_NOT_USE() const { return Args; }
-
   const Driver &getDriver() const { return D; }
   llvm::vfs::FileSystem &getVFS() const;
   const llvm::Triple &getTriple() const { return Triple; }
 
   /// Get the toolchain's aux triple, if it has one.
   ///
   /// Exactly what the aux triple represents depends on the toolchain, but for
   /// example when compiling CUDA code for the GPU, the triple might be NVPTX,

clang/lib/Driver/Driver.cpp

Diag(clang::diag::note_drv_command_failed_diag_msg)
       << "\n\n********************";
 }
 
 void Driver::setUpResponseFiles(Compilation &C, Command &Cmd) {
   // Since commandLineFitsWithinSystemLimits() may underestimate system's
   // capacity if the tool does not support response files, there is a chance/
   // that things will just work without a response file, so we silently just
   // skip it.
-  if (Cmd.getCreator().getResponseFilesSupport() == Tool::RF_None ||
+  if (Cmd.getResponseFileSupport().ResponseKind ==
+          ResponseFileSupport::RF_None ||
       llvm::sys::commandLineFitsWithinSystemLimits(Cmd.getExecutable(),
                                                    Cmd.getArguments()))
     return;
 
   std::string TmpName = GetTemporaryPath("response", "txt");
   Cmd.setResponseFile(C.addTempFile(C.getArgs().MakeArgString(TmpName)));
 }
 

clang/lib/Driver/Job.cpp

 #include <string>
 #include <system_error>
 #include <utility>
 
 using namespace clang;
 using namespace driver;
 
 Command::Command(const Action &Source, const Tool &Creator,
-                 const char *Executable,
+                 ResponseFileSupport ResponseSupport, const char *Executable,
                  const llvm::opt::ArgStringList &Arguments,
                  ArrayRef<InputInfo> Inputs)
-    : Source(Source), Creator(Creator), Executable(Executable),
-      Arguments(Arguments) {
+    : Source(Source), Creator(Creator), ResponseSupport(ResponseSupport),
+      Executable(Executable), Arguments(Arguments) {
   for (const auto &II : Inputs)
     if (II.isFilename())
       InputFilenames.push_back(II.getFilename());
 }
 
 /// Check if the compiler flag in question should be skipped when
 /// emitting a reproducer. Also track how many arguments it has and if the
 /// option is some kind of include path.
if (FlagRef.startswith("-fmodules-cache-path="))
     return true;
 
   SkipNum = 0;
   return false;
 }
 
 void Command::writeResponseFile(raw_ostream &OS) const {
   // In a file list, we only write the set of inputs to the response file
-  if (Creator.getResponseFilesSupport() == Tool::RF_FileList) {
+  if (ResponseSupport.ResponseKind == ResponseFileSupport::RF_FileList) {
     for (const auto *Arg : InputFileList) {
       OS << Arg << '\n';
     }
     return;
   }
 
   // In regular response files, we send all arguments to the response file.
   // Wrapping all arguments in double quotes ensures that both Unix tools and
void Command::writeResponseFile(raw_ostream &OS) const {
   }
 }
 
 void Command::buildArgvForResponseFile(
     llvm::SmallVectorImpl<const char *> &Out) const {
   // When not a file list, all arguments are sent to the response file.
   // This leaves us to set the argv to a single parameter, requesting the tool
   // to read the response file.
-  if (Creator.getResponseFilesSupport() != Tool::RF_FileList) {
+  if (ResponseSupport.ResponseKind != ResponseFileSupport::RF_FileList) {
     Out.push_back(Executable);
     Out.push_back(ResponseFileFlag.c_str());
     return;
   }
 
   llvm::StringSet<> Inputs;
   for (const auto *InputName : InputFileList)
     Inputs.insert(InputName);
   Out.push_back(Executable);
   // In a file list, build args vector ignoring parameters that will go in the
   // response file (elements of the InputFileList vector)
   bool FirstInput = true;
   for (const auto *Arg : Arguments) {
     if (Inputs.count(Arg) == 0) {
       Out.push_back(Arg);
     } else if (FirstInput) {
       FirstInput = false;
-      Out.push_back(Creator.getResponseFileFlag());
+      Out.push_back(ResponseSupport.ResponseFlag);
       Out.push_back(ResponseFile);
     }
   }
 }
 
 /// Rewrite relative include-like flag paths to absolute ones.
 static void
 rewriteIncludes(const llvm::ArrayRef<const char *> &Args, size_t Idx,
if (CrashInfo && HaveCrashVFS) {
     llvm::sys::printArg(OS, ModCachePath, Quote);
   }
 
   if (ResponseFile != nullptr) {
     OS << "\n Arguments passed via response file:\n";
     writeResponseFile(OS);
     // Avoiding duplicated newline terminator, since FileLists are
     // newline-separated.
-    if (Creator.getResponseFilesSupport() != Tool::RF_FileList)
+    if (ResponseSupport.ResponseKind != ResponseFileSupport::RF_FileList)
       OS << "\n";
     OS << " (end of response file)";
   }
 
   OS << Terminator;
 }
 
 void Command::setResponseFile(const char *FileName) {
   ResponseFile = FileName;
-  ResponseFileFlag = Creator.getResponseFileFlag();
+  ResponseFileFlag = ResponseSupport.ResponseFlag;
   ResponseFileFlag += FileName;
 }
 
 void Command::setEnvironment(llvm::ArrayRef<const char *> NewEnvironment) {
   Environment.reserve(NewEnvironment.size() + 1);
   Environment.assign(NewEnvironment.begin(), NewEnvironment.end());
   Environment.push_back(nullptr);
 }
if (ResponseFile == nullptr) {
     // Write file contents and build the Argv vector
     writeResponseFile(SS);
     buildArgvForResponseFile(Argv);
     Argv.push_back(nullptr);
     SS.flush();
 
     // Save the response file in the appropriate encoding
     if (std::error_code EC = writeFileWithEncoding(
-            ResponseFile, RespContents, Creator.getResponseFileEncoding())) {
+            ResponseFile, RespContents, ResponseSupport.ResponseEncoding)) {
       if (ErrMsg)
         *ErrMsg = EC.message();
       if (ExecutionFailed)
         *ExecutionFailed = true;
       // Return -1 by convention (see llvm/include/llvm/Support/Program.h) to
       // indicate the requested executable cannot be started.
       return -1;
     }
int Command::Execute(ArrayRef<llvm::Optional<StringRef>> Redirects,
 
   auto Args = llvm::toStringRefArray(Argv.data());
   return llvm::sys::ExecuteAndWait(Executable, Args, Env, Redirects,
                                    /*secondsToWait*/ 0,
                                    /*memoryLimit*/ 0, ErrMsg, ExecutionFailed);
 }
 
 CC1Command::CC1Command(const Action &Source, const Tool &Creator,
+                       ResponseFileSupport ResponseSupport,
                        const char *Executable,
                        const llvm::opt::ArgStringList &Arguments,
                        ArrayRef<InputInfo> Inputs)
-    : Command(Source, Creator, Executable, Arguments, Inputs) {
+    : Command(Source, Creator, ResponseSupport, Executable, Arguments, Inputs) {
   InProcess = true;
 }
 
 void CC1Command::Print(raw_ostream &OS, const char *Terminator, bool Quote,
                        CrashReportInfo *CrashInfo) const {
   if (InProcess)
     OS << " (in-process)\n";
   Command::Print(OS, Terminator, Quote, CrashInfo);

 
 void CC1Command::setEnvironment(llvm::ArrayRef<const char *> NewEnvironment) {
   // We don't support set a new environment when calling into ExecuteCC1Tool()
   llvm_unreachable(
       "The CC1Command doesn't support changing the environment vars!");
 }
 
 FallbackCommand::FallbackCommand(const Action &Source_, const Tool &Creator_,
+                                 ResponseFileSupport ResponseSupport,
                                  const char *Executable_,
                                  const llvm::opt::ArgStringList &Arguments_,
                                  ArrayRef<InputInfo> Inputs,
                                  std::unique_ptr<Command> Fallback_)
-    : Command(Source_, Creator_, Executable_, Arguments_, Inputs),
+    : Command(Source_, Creator_, ResponseSupport, Executable_, Arguments_,
+              Inputs),
       Fallback(std::move(Fallback_)) {}
 
 void FallbackCommand::Print(raw_ostream &OS, const char *Terminator,
                             bool Quote, CrashReportInfo *CrashInfo) const {
   Command::Print(OS, "", Quote, CrashInfo);
   OS << " ||";
   Fallback->Print(OS, Terminator, Quote, CrashInfo);
 }
int FallbackCommand::Execute(ArrayRef<llvm::Optional<StringRef>> Redirects,
   const Driver &D = getCreator().getToolChain().getDriver();
   D.Diag(diag::warn_drv_invoking_fallback) << Fallback->getExecutable();
 
   int SecondaryStatus = Fallback->Execute(Redirects, ErrMsg, ExecutionFailed);
   return SecondaryStatus;
 }
 
 ForceSuccessCommand::ForceSuccessCommand(
-    const Action &Source_, const Tool &Creator_, const char *Executable_,
+    const Action &Source_, const Tool &Creator_,
+    ResponseFileSupport ResponseSupport, const char *Executable_,
     const llvm::opt::ArgStringList &Arguments_, ArrayRef<InputInfo> Inputs)
-    : Command(Source_, Creator_, Executable_, Arguments_, Inputs) {}
+    : Command(Source_, Creator_, ResponseSupport, Executable_, Arguments_,
+              Inputs) {}
 
 void ForceSuccessCommand::Print(raw_ostream &OS, const char *Terminator,
                             bool Quote, CrashReportInfo *CrashInfo) const {
   Command::Print(OS, "", Quote, CrashInfo);
   OS << " || (exit 0)" << Terminator;
 }
 
 int ForceSuccessCommand::Execute(ArrayRef<llvm::Optional<StringRef>> Redirects,

clang/lib/Driver/Tool.cpp

 //===--- Tool.cpp - Compilation Tools -------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "clang/Driver/Tool.h"
 #include "InputInfo.h"
 
 using namespace clang::driver;
 
-Tool::Tool(const char *_Name, const char *_ShortName, const ToolChain &TC,
-           ResponseFileSupport _ResponseSupport,
-           llvm::sys::WindowsEncodingMethod _ResponseEncoding,
-           const char *_ResponseFlag)
-    : Name(_Name), ShortName(_ShortName), TheToolChain(TC),
-      ResponseSupport(_ResponseSupport), ResponseEncoding(_ResponseEncoding),
-      ResponseFlag(_ResponseFlag) {}
+Tool::Tool(const char *_Name, const char *_ShortName, const ToolChain &TC)
+    : Name(_Name), ShortName(_ShortName), TheToolChain(TC) {}
 
 Tool::~Tool() {
 }
 
 void Tool::ConstructJobMultipleOutputs(Compilation &C, const JobAction &JA,
                                        const InputInfoList &Outputs,
                                        const InputInfoList &Inputs,
                                        const llvm::opt::ArgList &TCArgs,
                                        const char *LinkingOutput) const {
   assert(Outputs.size() == 1 && "Expected only one output by default!");
   ConstructJob(C, JA, Outputs.front(), Inputs, TCArgs, LinkingOutput);
 }

clang/lib/Driver/ToolChains/AIX.cpp

void aix::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   if (Inputs.size() != 1)
     llvm_unreachable("Invalid number of input files.");
   const InputInfo &II = Inputs[0];
   assert((II.isFilename() || II.isNothing()) && "Invalid input.");
   if (II.isFilename())
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void aix::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                const InputInfo &Output,
                                const InputInfoList &Inputs, const ArgList &Args,
                                const char *LinkingOutput) const {
   const AIX &ToolChain = static_cast<const AIX &>(getToolChain());
   const Driver &D = ToolChain.getDriver();
if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
     // Support POSIX threads if "-pthreads" or "-pthread" is present.
     if (Args.hasArg(options::OPT_pthreads, options::OPT_pthread))
       CmdArgs.push_back("-lpthreads");
 
     CmdArgs.push_back("-lc");
   }
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 /// AIX - AIX tool chain which can call as(1) and ld(1) directly.
 AIX::AIX(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : ToolChain(D, Triple, Args) {
   getFilePaths().push_back(getDriver().SysRoot + "/usr/lib");
 }
 
 auto AIX::buildAssembler() const -> Tool * { return new aix::Assembler(*this); }
 
 auto AIX::buildLinker() const -> Tool * { return new aix::Linker(*this); }

clang/lib/Driver/ToolChains/AMDGPU.h

 #include <map>
 
 namespace clang {
 namespace driver {
 
 namespace tools {
 namespace amdgpu {
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("amdgpu::Linker", "ld.lld", TC) {}
+  Linker(const ToolChain &TC) : Tool("amdgpu::Linker", "ld.lld", TC) {}
   bool isLinkJob() const override { return true; }
   bool hasIntegratedCPP() const override { return false; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 

clang/lib/Driver/ToolChains/AMDGPU.cpp

void amdgpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                   const char *LinkingOutput) const {
 
   std::string Linker = getToolChain().GetProgramPath(getShortName());
   ArgStringList CmdArgs;
   AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
   CmdArgs.push_back("-shared");
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Linker),
-                                          CmdArgs, Inputs));
+  C.addCommand(
+      std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
+                                Args.MakeArgString(Linker), CmdArgs, Inputs));
 }
 
 void amdgpu::getAMDGPUTargetFeatures(const Driver &D,
                                      const llvm::opt::ArgList &Args,
                                      std::vector<StringRef> &Features) {
   if (const Arg *dAbi = Args.getLastArg(options::OPT_mamdgpu_debugger_abi))
     D.Diag(diag::err_drv_clang_unsupported) << dAbi->getAsString(Args);
 

clang/lib/Driver/ToolChains/AVR.h

private:
 
   llvm::Optional<std::string> findAVRLibcInstallation() const;
 };
 
 } // end namespace toolchains
 
 namespace tools {
 namespace AVR {
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
   Linker(const llvm::Triple &Triple, const ToolChain &TC, bool LinkStdlib)
-      : GnuTool("AVR::Linker", "avr-ld", TC), Triple(Triple),
+      : Tool("AVR::Linker", "avr-ld", TC), Triple(Triple),
         LinkStdlib(LinkStdlib) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/AVR.cpp

if (LinkStdlib) {
 
     // Specify the family name as the emulation mode to use.
     // This is almost always required because otherwise avr-ld
     // will assume 'avr2' and warn about the program being larger
     // than the bare minimum supports.
     CmdArgs.push_back(Args.MakeArgString(std::string("-m") + *FamilyName));
   }
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Linker),
-                                          CmdArgs, Inputs));
+  C.addCommand(
+      std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
+                                Args.MakeArgString(Linker), CmdArgs, Inputs));
 }
 
 llvm::Optional<std::string> AVRToolChain::findAVRLibcInstallation() const {
   for (StringRef PossiblePath : PossibleAVRLibcLocations) {
     // Return the first avr-libc installation that exists.
     if (llvm::sys::fs::is_directory(PossiblePath))
       return Optional<std::string>(std::string(PossiblePath));
   }
 
   return llvm::None;
 }

clang/lib/Driver/ToolChains/Ananas.h

 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 
 /// ananas -- Directly call GNU Binutils assembler and linker
 namespace ananas {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
-  Assembler(const ToolChain &TC)
-      : GnuTool("ananas::Assembler", "assembler", TC) {}
+  Assembler(const ToolChain &TC) : Tool("ananas::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("ananas::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("ananas::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/Ananas.cpp

void ananas::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void ananas::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                   const InputInfo &Output,
                                   const InputInfoList &Inputs,
                                   const ArgList &Args,
                                   const char *LinkingOutput) const {
   const ToolChain &ToolChain = getToolChain();
if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
     if (Args.hasArg(options::OPT_shared) || Args.hasArg(options::OPT_pie))
       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtendS.o")));
     else
       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
   }
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 // Ananas - Ananas tool chain which can call as(1) and ld(1) directly.
 
 Ananas::Ananas(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   getFilePaths().push_back(getDriver().SysRoot + "/usr/lib");
 }
 
 Tool *Ananas::buildAssembler() const {
   return new tools::ananas::Assembler(*this);
 }
 
 Tool *Ananas::buildLinker() const { return new tools::ananas::Linker(*this); }

clang/lib/Driver/ToolChains/BareMetal.cpp

if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
     CmdArgs.push_back("-lm");
 
     TC.AddLinkRuntimeLib(Args, CmdArgs);
   }
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
-  C.addCommand(std::make_unique<Command>(JA, *this,
-                                          Args.MakeArgString(TC.GetLinkerPath()),
-                                          CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
 }

clang/lib/Driver/ToolChains/Clang.h

void ConstructJob(Compilation &C, const JobAction &JA,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 /// Clang integrated assembler tool.
 class LLVM_LIBRARY_VISIBILITY ClangAs : public Tool {
 public:
   ClangAs(const ToolChain &TC)
-      : Tool("clang::as", "clang integrated assembler", TC, RF_Full) {}
+      : Tool("clang::as", "clang integrated assembler", TC) {}
   void AddMIPSTargetArgs(const llvm::opt::ArgList &Args,
                          llvm::opt::ArgStringList &CmdArgs) const;
   void AddX86TargetArgs(const llvm::opt::ArgList &Args,
                         llvm::opt::ArgStringList &CmdArgs) const;
   void AddRISCVTargetArgs(const llvm::opt::ArgList &Args,
                           llvm::opt::ArgStringList &CmdArgs) const;
   bool hasGoodDiagnostics() const override { return true; }
   bool hasIntegratedAssembler() const override { return false; }

clang/lib/Driver/ToolChains/Clang.cpp

if (C.getDriver().embedBitcodeInObject() && !C.getDriver().isUsingLTO() &&
     for (const auto &II : Inputs) {
       addDashXForInput(Args, II, CmdArgs);
       if (II.isFilename())
         CmdArgs.push_back(II.getFilename());
       else
         II.getInputArg().renderAsInput(Args, CmdArgs);
     }
 
-    C.addCommand(std::make_unique<Command>(JA, *this, D.getClangProgramPath(),
-                                            CmdArgs, Inputs));
+    C.addCommand(
+        std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileUTF8(),
+                                  D.getClangProgramPath(), CmdArgs, Inputs));
     return;
   }
 
   if (C.getDriver().embedBitcodeMarkerOnly() && !C.getDriver().isUsingLTO())
     CmdArgs.push_back("-fembed-bitcode=marker");
 
   // We normally speed up the clang process a bit by skipping destructors at
   // exit, but when we're generating diagnostics we can rely on some of the

 
   // Finally add the compile command to the compilation.
   if (Args.hasArg(options::OPT__SLASH_fallback) &&
       Output.getType() == types::TY_Object &&
       (InputType == types::TY_C || InputType == types::TY_CXX)) {
     auto CLCommand =
         getCLFallback()->GetCommand(C, JA, Output, Inputs, Args, LinkingOutput);
     C.addCommand(std::make_unique<FallbackCommand>(
-        JA, *this, Exec, CmdArgs, Inputs, std::move(CLCommand)));
+        JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs,
+        std::move(CLCommand)));
   } else if (Args.hasArg(options::OPT__SLASH_fallback) &&
              isa<PrecompileJobAction>(JA)) {
     // In /fallback builds, run the main compilation even if the pch generation
     // fails, so that the main compilation's fallback to cl.exe runs.
-    C.addCommand(std::make_unique<ForceSuccessCommand>(JA, *this, Exec,
-                                                        CmdArgs, Inputs));
+    C.addCommand(std::make_unique<ForceSuccessCommand>(
+        JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
   } else if (D.CC1Main && !D.CCGenDiagnostics) {
     // Invoke the CC1 directly in this process
-    C.addCommand(
-        std::make_unique<CC1Command>(JA, *this, Exec, CmdArgs, Inputs));
+    C.addCommand(std::make_unique<CC1Command>(
+        JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
   } else {
-    C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+    C.addCommand(std::make_unique<Command>(
+        JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
   }
 
   // Make the compile command echo its inputs for /showFilenames.
   if (Output.getType() == types::TY_Object &&
       Args.hasFlag(options::OPT__SLASH_showFilenames,
                    options::OPT__SLASH_showFilenames_, false)) {
     C.getJobs().getJobs().back()->PrintInputFilenames = true;
   }

   // Disable warnings for clang -E -emit-llvm foo.c
   Args.ClaimAllArgs(options::OPT_emit_llvm);
 }
 
 Clang::Clang(const ToolChain &TC)
     // CAUTION! The first constructor argument ("clang") is not arbitrary,
     // as it is for other tools. Some operations on a Tool actually test
     // whether that tool is Clang based on the Tool's Name as a string.
-    : Tool("clang", "clang frontend", TC, RF_Full) {}
+    : Tool("clang", "clang frontend", TC) {}
 
 Clang::~Clang() {}
 
 /// Add options related to the Objective-C runtime/ABI.
 ///
 /// Returns true if the runtime is non-fragile.
 ObjCRuntime Clang::AddObjCRuntimeArgs(const ArgList &args,
                                       const InputInfoList &inputs,
if (getDebugFissionKind(D, Args, A) == DwarfFissionKind::Split &&
     CmdArgs.push_back("-split-dwarf-output");
     CmdArgs.push_back(SplitDebugName(Args, Input, Output));
   }
 
   assert(Input.isFilename() && "Invalid input.");
   CmdArgs.push_back(Input.getFilename());
 
   const char *Exec = getToolChain().getDriver().getClangProgramPath();
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
 }
 
 // Begin OffloadBundler
 
 void OffloadBundler::ConstructJob(Compilation &C, const JobAction &JA,
                                   const InputInfo &Output,
                                   const InputInfoList &Inputs,
                                   const llvm::opt::ArgList &TCArgs,
if (const auto *OA = dyn_cast<OffloadAction>(JA.getInputs()[I])) {
       });
     }
     UB += CurTC->getInputFilename(Inputs[I]);
   }
   CmdArgs.push_back(TCArgs.MakeArgString(UB));
 
   // All the inputs are encoded as commands.
   C.addCommand(std::make_unique<Command>(
-      JA, *this,
+      JA, *this, ResponseFileSupport::None(),
       TCArgs.MakeArgString(getToolChain().GetProgramPath(getShortName())),
       CmdArgs, None));
 }
 
 void OffloadBundler::ConstructJobMultipleOutputs(
     Compilation &C, const JobAction &JA, const InputInfoList &Outputs,
     const InputInfoList &Inputs, const llvm::opt::ArgList &TCArgs,
     const char *LinkingOutput) const {
if (I)
       UB += ',';
     UB += DepInfo[I].DependentToolChain->getInputFilename(Outputs[I]);
   }
   CmdArgs.push_back(TCArgs.MakeArgString(UB));
   CmdArgs.push_back("-unbundle");
 
   // All the inputs are encoded as commands.
   C.addCommand(std::make_unique<Command>(
-      JA, *this,
+      JA, *this, ResponseFileSupport::None(),
       TCArgs.MakeArgString(getToolChain().GetProgramPath(getShortName())),
       CmdArgs, None));
 }
 
 void OffloadWrapper::ConstructJob(Compilation &C, const JobAction &JA,
                                   const InputInfo &Output,
                                   const InputInfoList &Inputs,
                                   const ArgList &Args,
void OffloadWrapper::ConstructJob(Compilation &C, const JobAction &JA,
 
   // Add inputs.
   for (const InputInfo &I : Inputs) {
     assert(I.isFilename() && "Invalid input.");
     CmdArgs.push_back(I.getFilename());
   }
 
   C.addCommand(std::make_unique<Command>(
-      JA, *this,
+      JA, *this, ResponseFileSupport::None(),
       Args.MakeArgString(getToolChain().GetProgramPath(getShortName())),
       CmdArgs, Inputs));
 }

clang/lib/Driver/ToolChains/CloudABI.h

 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 
 /// cloudabi -- Directly call GNU Binutils linker
 namespace cloudabi {
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("cloudabi::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("cloudabi::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/CloudABI.cpp

if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
     CmdArgs.push_back("-lc");
     CmdArgs.push_back("-lcompiler_rt");
   }
 
   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles))
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 // CloudABI - CloudABI tool chain which can call ld(1) directly.
 
 CloudABI::CloudABI(const Driver &D, const llvm::Triple &Triple,
                    const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   SmallString<128> P(getDriver().Dir);

clang/lib/Driver/ToolChains/CommonArgs.cpp

void tools::SplitDebugInfo(const ToolChain &TC, Compilation &C, const Tool &T,
   ExtractArgs.push_back(Output.getFilename());
   ExtractArgs.push_back(OutFile);
 
   const char *Exec =
       Args.MakeArgString(TC.GetProgramPath(CLANG_DEFAULT_OBJCOPY));
   InputInfo II(types::TY_Object, Output.getFilename(), Output.getFilename());
 
   // First extract the dwo sections.
-  C.addCommand(std::make_unique<Command>(JA, T, Exec, ExtractArgs, II));
+  C.addCommand(std::make_unique<Command>(
+      JA, T, ResponseFileSupport::AtFileCurCP(), Exec, ExtractArgs, II));
 
   // Then remove them from the original .o file.
-  C.addCommand(std::make_unique<Command>(JA, T, Exec, StripArgs, II));
+  C.addCommand(std::make_unique<Command>(
+      JA, T, ResponseFileSupport::AtFileCurCP(), Exec, StripArgs, II));
 }
 
 // Claim options we don't want to warn if they are unused. We do this for
 // options that build systems might add but are unused when assembling or only
 // running the preprocessor for example.
 void tools::claimNoWarnArgs(const ArgList &Args) {
   // Don't warn about unused -f(no-)?lto.  This can happen when we're
   // preprocessing, precompiling or assembling.

clang/lib/Driver/ToolChains/CrossWindows.h

public:
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC)
-      : Tool("CrossWindows::Linker", "ld", TC, RF_Full) {}
+  Linker(const ToolChain &TC) : Tool("CrossWindows::Linker", "ld", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/CrossWindows.cpp

void tools::CrossWindows::Assembler::ConstructJob(
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &Input : Inputs)
     CmdArgs.push_back(Input.getFilename());
 
   const std::string Assembler = TC.GetProgramPath("as");
   Exec = Args.MakeArgString(Assembler);
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void tools::CrossWindows::Linker::ConstructJob(
     Compilation &C, const JobAction &JA, const InputInfo &Output,
     const InputInfoList &Inputs, const ArgList &Args,
     const char *LinkingOutput) const {
   const auto &TC =
       static_cast<const toolchains::CrossWindowsToolChain &>(getToolChain());
if (Args.hasArg(options::OPT_shared)) {
       CmdArgs.push_back(Args.MakeArgString(TC.getArch() == llvm::Triple::x86
                                                ? "___asan_seh_interceptor"
                                                : "__asan_seh_interceptor"));
     }
   }
 
   Exec = Args.MakeArgString(TC.GetLinkerPath());
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
 }
 
 CrossWindowsToolChain::CrossWindowsToolChain(const Driver &D,
                                              const llvm::Triple &T,
                                              const llvm::opt::ArgList &Args)
     : Generic_GCC(D, T, Args) {}
 
 bool CrossWindowsToolChain::IsUnwindTablesDefault(const ArgList &Args) const {

clang/lib/Driver/ToolChains/Cuda.h

 };
 
 namespace tools {
 namespace NVPTX {
 
 // Run ptxas, the NVPTX assembler.
 class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
  public:
-   Assembler(const ToolChain &TC)
-       : Tool("NVPTX::Assembler", "ptxas", TC, RF_Full, llvm::sys::WEM_UTF8,
-              "--options-file") {}
+   Assembler(const ToolChain &TC) : Tool("NVPTX::Assembler", "ptxas", TC) {}
 
    bool hasIntegratedCPP() const override { return false; }
 
    void ConstructJob(Compilation &C, const JobAction &JA,
                      const InputInfo &Output, const InputInfoList &Inputs,
                      const llvm::opt::ArgList &TCArgs,
                      const char *LinkingOutput) const override;
 };
 
 // Runs fatbinary, which combines GPU object files ("cubin" files) and/or PTX
 // assembly into a single output file.
 class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
  public:
-   Linker(const ToolChain &TC)
-       : Tool("NVPTX::Linker", "fatbinary", TC, RF_Full, llvm::sys::WEM_UTF8,
-              "--options-file") {}
+   Linker(const ToolChain &TC) : Tool("NVPTX::Linker", "fatbinary", TC) {}
 
    bool hasIntegratedCPP() const override { return false; }
 
    void ConstructJob(Compilation &C, const JobAction &JA,
                      const InputInfo &Output, const InputInfoList &Inputs,
                      const llvm::opt::ArgList &TCArgs,
                      const char *LinkingOutput) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY OpenMPLinker : public Tool {
  public:
    OpenMPLinker(const ToolChain &TC)
-       : Tool("NVPTX::OpenMPLinker", "nvlink", TC, RF_Full, llvm::sys::WEM_UTF8,
-              "--options-file") {}
+       : Tool("NVPTX::OpenMPLinker", "nvlink", TC) {}
 
    bool hasIntegratedCPP() const override { return false; }
 
    void ConstructJob(Compilation &C, const JobAction &JA,
                      const InputInfo &Output, const InputInfoList &Inputs,
                      const llvm::opt::ArgList &TCArgs,
                      const char *LinkingOutput) const override;
 };

clang/lib/Driver/ToolChains/Cuda.cpp

void NVPTX::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   if (Relocatable)
     CmdArgs.push_back("-c");
 
   const char *Exec;
   if (Arg *A = Args.getLastArg(options::OPT_ptxas_path_EQ))
     Exec = A->getValue();
   else
     Exec = Args.MakeArgString(TC.GetProgramPath("ptxas"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this,
+      ResponseFileSupport{ResponseFileSupport::RF_Full, llvm::sys::WEM_UTF8,
+                          "--options-file"},
+      Exec, CmdArgs, Inputs));
 }
 
 static bool shouldIncludePTX(const ArgList &Args, const char *gpu_arch) {
   bool includePTX = true;
   for (Arg *A : Args) {
     if (!(A->getOption().matches(options::OPT_cuda_include_ptx_EQ) ||
           A->getOption().matches(options::OPT_no_cuda_include_ptx_EQ)))
       continue;
for (const auto& II : Inputs) {
     CmdArgs.push_back(Args.MakeArgString(llvm::Twine("--image=profile=") +
                                          Arch + ",file=" + II.getFilename()));
   }
 
   for (const auto& A : Args.getAllArgValues(options::OPT_Xcuda_fatbinary))
     CmdArgs.push_back(Args.MakeArgString(A));
 
   const char *Exec = Args.MakeArgString(TC.GetProgramPath("fatbinary"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this,
+      ResponseFileSupport{ResponseFileSupport::RF_Full, llvm::sys::WEM_UTF8,
+                          "--options-file"},
+      Exec, CmdArgs, Inputs));
 }
 
 void NVPTX::OpenMPLinker::ConstructJob(Compilation &C, const JobAction &JA,
                                        const InputInfo &Output,
                                        const InputInfoList &Inputs,
                                        const ArgList &Args,
                                        const char *LinkingOutput) const {
   const auto &TC =
for (const auto &II : Inputs) {
     const char *CubinF = C.addTempFile(
         C.getArgs().MakeArgString(getToolChain().getInputFilename(II)));
 
     CmdArgs.push_back(CubinF);
   }
 
   const char *Exec =
       Args.MakeArgString(getToolChain().GetProgramPath("nvlink"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this,
+      ResponseFileSupport{ResponseFileSupport::RF_Full, llvm::sys::WEM_UTF8,
+                          "--options-file"},
+      Exec, CmdArgs, Inputs));
 }
 
 /// CUDA toolchain.  Our assembler is ptxas, and our "linker" is fatbinary,
 /// which isn't properly a linker but nonetheless performs the step of stitching
 /// together object files from the assembler into a single blob.
 
 CudaToolChain::CudaToolChain(const Driver &D, const llvm::Triple &Triple,
                              const ToolChain &HostTC, const ArgList &Args,

clang/lib/Driver/ToolChains/Darwin.h

protected:
   void AddMachOArch(const llvm::opt::ArgList &Args,
                     llvm::opt::ArgStringList &CmdArgs) const;
 
   const toolchains::MachO &getMachOToolChain() const {
     return reinterpret_cast<const toolchains::MachO &>(getToolChain());
   }
 
 public:
-  MachOTool(
-      const char *Name, const char *ShortName, const ToolChain &TC,
-      ResponseFileSupport ResponseSupport = RF_None,
-      llvm::sys::WindowsEncodingMethod ResponseEncoding = llvm::sys::WEM_UTF8,
-      const char *ResponseFlag = "@")
-      : Tool(Name, ShortName, TC, ResponseSupport, ResponseEncoding,
-             ResponseFlag) {}
+  MachOTool(const char *Name, const char *ShortName, const ToolChain &TC)
+      : Tool(Name, ShortName, TC) {}
 };
 
 class LLVM_LIBRARY_VISIBILITY Assembler : public MachOTool {
 public:
   Assembler(const ToolChain &TC)
       : MachOTool("darwin::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY Linker : public MachOTool {
   bool NeedsTempPath(const InputInfoList &Inputs) const;
   void AddLinkArgs(Compilation &C, const llvm::opt::ArgList &Args,
                    llvm::opt::ArgStringList &CmdArgs,
-                   const InputInfoList &Inputs) const;
+                   const InputInfoList &Inputs, unsigned Version[5]) const;
 
 public:
-  Linker(const ToolChain &TC, bool UseAtFile)
-      : MachOTool("darwin::Linker", "linker", TC,
-                  UseAtFile ? RF_Full : RF_FileList, llvm::sys::WEM_UTF8,
-                  UseAtFile ? "@" : "-filelist") {}
+  Linker(const ToolChain &TC) : MachOTool("darwin::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/Darwin.cpp

void darwin::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
   CmdArgs.push_back(Output.getFilename());
 
   assert(Input.isFilename() && "Invalid input.");
   CmdArgs.push_back(Input.getFilename());
 
   // asm_final spec is empty.
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void darwin::MachOTool::anchor() {}
 
 void darwin::MachOTool::AddMachOArch(const ArgList &Args,
                                      ArgStringList &CmdArgs) const {
   StringRef ArchName = getMachOToolChain().getMachOArchName(Args);
 
static bool shouldLinkerNotDedup(bool IsLinkerOnlyAction, const ArgList &Args) {
 
   if (!IsLinkerOnlyAction) // Implicit -O0 for compile+linker only.
     return true;
   return false;
 }
 
 void darwin::Linker::AddLinkArgs(Compilation &C, const ArgList &Args,
                                  ArgStringList &CmdArgs,
-                                 const InputInfoList &Inputs) const {
+                                 const InputInfoList &Inputs,
+                                 unsigned Version[5]) const {
   const Driver &D = getToolChain().getDriver();
   const toolchains::MachO &MachOTC = getMachOToolChain();
 
-  unsigned Version[5] = {0, 0, 0, 0, 0};
-  if (Arg *A = Args.getLastArg(options::OPT_mlinker_version_EQ)) {
-    if (!Driver::GetReleaseVersion(A->getValue(), Version))
-      D.Diag(diag::err_drv_invalid_version_number) << A->getAsString(Args);
-  }
-
   // Newer linkers support -demangle. Pass it if supported and not disabled by
   // the user.
   if (Version[0] >= 100 && !Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
     CmdArgs.push_back("-demangle");
 
   if (Args.hasArg(options::OPT_rdynamic) && Version[0] >= 137)
     CmdArgs.push_back("-export_dynamic");
 
void darwin::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   /// Hack(tm) to ignore linking errors when we are doing ARC migration.
   if (Args.hasArg(options::OPT_ccc_arcmt_check,
                   options::OPT_ccc_arcmt_migrate)) {
     for (const auto &Arg : Args)
       Arg->claim();
     const char *Exec =
         Args.MakeArgString(getToolChain().GetProgramPath("touch"));
     CmdArgs.push_back(Output.getFilename());
-    C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, None));
+    C.addCommand(std::make_unique<Command>(
+        JA, *this, ResponseFileSupport::None(), Exec, CmdArgs, None));
     return;
   }
 
+  unsigned Version[5] = {0, 0, 0, 0, 0};
+  if (Arg *A = Args.getLastArg(options::OPT_mlinker_version_EQ)) {
+    if (!Driver::GetReleaseVersion(A->getValue(), Version))
+      getToolChain().getDriver().Diag(diag::err_drv_invalid_version_number)
+          << A->getAsString(Args);
+  }
+
   // I'm not sure why this particular decomposition exists in gcc, but
   // we follow suite for ease of comparison.
-  AddLinkArgs(C, Args, CmdArgs, Inputs);
+  AddLinkArgs(C, Args, CmdArgs, Inputs, Version);
 
   if (willEmitRemarks(Args) &&
       checkRemarksOptions(getToolChain().getDriver(), Args,
                           getToolChain().getTriple()))
     renderRemarksOptions(Args, CmdArgs, getToolChain().getTriple(), Output, JA);
 
   // Propagate the -moutline flag to the linker in LTO.
   if (Arg *A =
if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
     if (Arg *A = Args.getLastArg(options::OPT_fveclib)) {
       if (A->getValue() == StringRef("Accelerate")) {
         CmdArgs.push_back("-framework");
         CmdArgs.push_back("Accelerate");
       }
     }
   }
 
+  ResponseFileSupport ResponseSupport = ResponseFileSupport::AtFileUTF8();
+  if (Version[0] < 607) {
+    // For older versions of the linker, use the legacy filelist method instead.
+    ResponseSupport = {ResponseFileSupport::RF_FileList, llvm::sys::WEM_UTF8,
+                       "-filelist"};
+  }
+
   const char *Exec = Args.MakeArgString(getToolChain().GetLinkerPath());
-  std::unique_ptr<Command> Cmd =
-      std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs);
+  std::unique_ptr<Command> Cmd = std::make_unique<Command>(
+      JA, *this, ResponseSupport, Exec, CmdArgs, Inputs);
   Cmd->setInputFileList(std::move(InputFileList));
   C.addCommand(std::move(Cmd));
 }
 
 void darwin::Lipo::ConstructJob(Compilation &C, const JobAction &JA,
                                 const InputInfo &Output,
                                 const InputInfoList &Inputs,
                                 const ArgList &Args,
                                 const char *LinkingOutput) const {
   ArgStringList CmdArgs;
 
   CmdArgs.push_back("-create");
   assert(Output.isFilename() && "Unexpected lipo output.");
 
   CmdArgs.push_back("-output");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs) {
     assert(II.isFilename() && "Unexpected lipo input.");
     CmdArgs.push_back(II.getFilename());
   }
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("lipo"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void darwin::Dsymutil::ConstructJob(Compilation &C, const JobAction &JA,
                                     const InputInfo &Output,
                                     const InputInfoList &Inputs,
                                     const ArgList &Args,
                                     const char *LinkingOutput) const {
   ArgStringList CmdArgs;
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   assert(Inputs.size() == 1 && "Unable to handle multiple inputs.");
   const InputInfo &Input = Inputs[0];
   assert(Input.isFilename() && "Unexpected dsymutil input.");
   CmdArgs.push_back(Input.getFilename());
 
   const char *Exec =
       Args.MakeArgString(getToolChain().GetProgramPath("dsymutil"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void darwin::VerifyDebug::ConstructJob(Compilation &C, const JobAction &JA,
                                        const InputInfo &Output,
                                        const InputInfoList &Inputs,
                                        const ArgList &Args,
                                        const char *LinkingOutput) const {
   ArgStringList CmdArgs;
   CmdArgs.push_back("--verify");
   CmdArgs.push_back("--debug-info");
   CmdArgs.push_back("--eh-frame");
   CmdArgs.push_back("--quiet");
 
   assert(Inputs.size() == 1 && "Unable to handle multiple inputs.");
   const InputInfo &Input = Inputs[0];
   assert(Input.isFilename() && "Unexpected verify input");
 
   // Grabbing the output of the earlier dsymutil run.
   CmdArgs.push_back(Input.getFilename());
 
   const char *Exec =
       Args.MakeArgString(getToolChain().GetProgramPath("dwarfdump"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 MachO::MachO(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : ToolChain(D, Triple, Args) {
   // We expect 'as', 'ld', etc. to be adjacent to our install dir.
   getProgramPaths().push_back(getDriver().getInstalledDir());
   if (getDriver().getInstalledDir() != getDriver().Dir)
     getProgramPaths().push_back(getDriver().Dir);
case Action::VerifyDebugInfoJobClass:
     if (!VerifyDebug)
       VerifyDebug.reset(new tools::darwin::VerifyDebug(*this));
     return VerifyDebug.get();
   default:
     return ToolChain::getTool(AC);
   }
 }
 
-Tool *MachO::buildLinker() const {
-  // Determine whether to use an @responsefile or the old -filelist mechanism.
-  bool UseAtFile = false;
-  unsigned Version[5] = {0, 0, 0, 0, 0};
-  if (Arg *A =
-          getArgs_DO_NOT_USE().getLastArg(options::OPT_mlinker_version_EQ)) {
-    // We don't need to diagnose a parse error here, it'll be caught in
-    // ConstructJob.
-    if (Driver::GetReleaseVersion(A->getValue(), Version)) {
-      if (Version[0] >= 607)
-        UseAtFile = true;
-    }
-  }
-
-  return new tools::darwin::Linker(*this, UseAtFile);
-}
+Tool *MachO::buildLinker() const { return new tools::darwin::Linker(*this); }
 
 Tool *MachO::buildAssembler() const {
   return new tools::darwin::Assembler(*this);
 }
 
 DarwinClang::DarwinClang(const Driver &D, const llvm::Triple &Triple,
                          const ArgList &Args)
     : Darwin(D, Triple, Args) {}

clang/lib/Driver/ToolChains/DragonFly.h

 #include "clang/Driver/Tool.h"
 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 /// dragonfly -- Directly call GNU Binutils assembler and linker
 namespace dragonfly {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
   Assembler(const ToolChain &TC)
-      : GnuTool("dragonfly::Assembler", "assembler", TC) {}
+      : Tool("dragonfly::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("dragonfly::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("dragonfly::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/DragonFly.cpp

void dragonfly::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void dragonfly::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                      const InputInfo &Output,
                                      const InputInfoList &Inputs,
                                      const ArgList &Args,
                                      const char *LinkingOutput) const {
   const Driver &D = getToolChain().getDriver();
else
       CmdArgs.push_back(
           Args.MakeArgString(getToolChain().GetFilePath("crtend.o")));
     CmdArgs.push_back(Args.MakeArgString(getToolChain().GetFilePath("crtn.o")));
   }
 
   getToolChain().addProfileRTLibs(Args, CmdArgs);
 
   const char *Exec = Args.MakeArgString(getToolChain().GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 /// DragonFly - DragonFly tool chain which can call as(1) and ld(1) directly.
 
 DragonFly::DragonFly(const Driver &D, const llvm::Triple &Triple,
                      const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
 

clang/lib/Driver/ToolChains/Flang.cpp

void Flang::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   const InputInfo &Input = Inputs[0];
   assert(Input.isFilename() && "Invalid input.");
   CmdArgs.push_back(Input.getFilename());
 
   const auto& D = C.getDriver();
   const char* Exec = Args.MakeArgString(D.GetProgramPath("flang", TC));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
 }
 
-Flang::Flang(const ToolChain &TC)
-    : Tool("flang", "flang frontend", TC, RF_Full) {}
+Flang::Flang(const ToolChain &TC) : Tool("flang", "flang frontend", TC) {}
 
 Flang::~Flang() {}

clang/lib/Driver/ToolChains/FreeBSD.h

 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 
 /// freebsd -- Directly call GNU Binutils assembler and linker
 namespace freebsd {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
   Assembler(const ToolChain &TC)
-      : GnuTool("freebsd::Assembler", "assembler", TC) {}
+      : Tool("freebsd::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("freebsd::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("freebsd::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/FreeBSD.cpp

void freebsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void freebsd::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                    const InputInfo &Output,
                                    const InputInfoList &Inputs,
                                    const ArgList &Args,
                                    const char *LinkingOutput) const {
   const toolchains::FreeBSD &ToolChain =
if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
     else
       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
   }
 
   ToolChain.addProfileRTLibs(Args, CmdArgs);
 
   const char *Exec = Args.MakeArgString(getToolChain().GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 /// FreeBSD - FreeBSD tool chain which can call as(1) and ld(1) directly.
 
 FreeBSD::FreeBSD(const Driver &D, const llvm::Triple &Triple,
                  const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
 

clang/lib/Driver/ToolChains/Fuchsia.cpp

if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
 
     if (Args.hasArg(options::OPT_fsplit_stack))
       CmdArgs.push_back("--wrap=pthread_create");
 
     if (!Args.hasArg(options::OPT_nolibc))
       CmdArgs.push_back("-lc");
   }
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 /// Fuchsia - Fuchsia tool chain which can call as(1) and ld(1) directly.
 
 Fuchsia::Fuchsia(const Driver &D, const llvm::Triple &Triple,
                  const ArgList &Args)
     : ToolChain(D, Triple, Args) {
   getProgramPaths().push_back(getDriver().getInstalledDir());

clang/lib/Driver/ToolChains/Gnu.h

 };
 
 bool findMIPSMultilibs(const Driver &D, const llvm::Triple &TargetTriple,
                        StringRef Path, const llvm::opt::ArgList &Args,
                        DetectedMultilibs &Result);
 
 namespace tools {
 
-/// Base class for all GNU tools that provide the same behavior when
-/// it comes to response files support
-class LLVM_LIBRARY_VISIBILITY GnuTool : public Tool {
-  virtual void anchor();
-
-public:
-  GnuTool(const char *Name, const char *ShortName, const ToolChain &TC)
-      : Tool(Name, ShortName, TC, RF_Full, llvm::sys::WEM_CurrentCodePage) {}
-};
-
 /// Directly call GNU Binutils' assembler and linker.
 namespace gnutools {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
-  Assembler(const ToolChain &TC) : GnuTool("GNU::Assembler", "assembler", TC) {}
+  Assembler(const ToolChain &TC) : Tool("GNU::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("GNU::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("GNU::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY StaticLibTool : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY StaticLibTool : public Tool {
 public:
   StaticLibTool(const ToolChain &TC)
-      : GnuTool("GNU::StaticLibTool", "static-lib-linker", TC) {}
+      : Tool("GNU::StaticLibTool", "static-lib-linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 } // end namespace gnutools
 
 /// gcc - Generic GCC tool implementations.
 namespace gcc {
-class LLVM_LIBRARY_VISIBILITY Common : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Common : public Tool {
 public:
   Common(const char *Name, const char *ShortName, const ToolChain &TC)
-      : GnuTool(Name, ShortName, TC) {}
+      : Tool(Name, ShortName, TC) {}
 
   // A gcc tool has an "integrated" assembler that it will call to produce an
   // object. Let it use that assembler so that we don't have to deal with
   // assembly syntax incompatibilities.
   bool hasIntegratedAssembler() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,

clang/lib/Driver/ToolChains/Gnu.cpp

 using namespace clang::driver;
 using namespace clang::driver::toolchains;
 using namespace clang;
 using namespace llvm::opt;
 
 using tools::addMultilibFlag;
 using tools::addPathIfExists;
 
-void tools::GnuTool::anchor() {}
-
 static bool forwardToGCC(const Option &O) {
   // Don't forward inputs from the original command line.  They are added from
   // InputInfoList.
   return O.getKind() != Option::InputClass &&
          !O.hasFlag(options::DriverOption) && !O.hasFlag(options::LinkerInput);
 }
 
 // Switch CPU names not recognized by GNU assembler to a close CPU that it does
void tools::gcc::Common::ConstructJob(Compilation &C, const JobAction &JA,
   if (!customGCCName.empty())
     GCCName = customGCCName.c_str();
   else if (D.CCCIsCXX()) {
     GCCName = "g++";
   } else
     GCCName = "gcc";
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath(GCCName));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void tools::gcc::Preprocessor::RenderExtraToolArgs(
     const JobAction &JA, ArgStringList &CmdArgs) const {
   CmdArgs.push_back("-E");
 }
 
 void tools::gcc::Compiler::RenderExtraToolArgs(const JobAction &JA,
void tools::gnutools::StaticLibTool::ConstructJob(
   if (Output.isFilename() && llvm::sys::fs::exists(OutputFileName)) {
     if (std::error_code EC = llvm::sys::fs::remove(OutputFileName)) {
       D.Diag(diag::err_drv_unable_to_remove_file) << EC.message();
       return;
     }
   }
 
   const char *Exec = Args.MakeArgString(getToolChain().GetStaticLibToolPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void tools::gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                            const InputInfo &Output,
                                            const InputInfoList &Inputs,
                                            const ArgList &Args,
                                            const char *LinkingOutput) const {
   // FIXME: The Linker class constructor takes a ToolChain and not a
if (!Args.hasArg(options::OPT_nostartfiles) && !IsIAMCU) {
       if (!isAndroid)
         CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
     }
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_T);
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void tools::gnutools::Assembler::ConstructJob(Compilation &C,
                                               const JobAction &JA,
                                               const InputInfo &Output,
                                               const InputInfoList &Inputs,
                                               const ArgList &Args,
                                               const char *LinkingOutput) const {
void tools::gnutools::Assembler::ConstructJob(Compilation &C,
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec =
       Args.MakeArgString(getToolChain().GetProgramPath(DefaultAssembler));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 
   // Handle the debug info splitting at object creation time if we're
   // creating an object.
   // TODO: Currently only works on linux with newer objcopy.
   if (Args.hasArg(options::OPT_gsplit_dwarf) &&
       getToolChain().getTriple().isOSLinux())
     SplitDebugInfo(getToolChain(), C, *this, JA, Args, Output,
                    SplitDebugName(Args, Inputs[0], Output));

clang/lib/Driver/ToolChains/HIP.cpp

ArgStringList LldArgs{"-flavor",
                         "-shared",
                         "-mllvm",
                         "-amdgpu-internalize-symbols",
                         "-o",
                         Output.getFilename()};
   for (auto Input : Inputs)
     LldArgs.push_back(Input.getFilename());
   const char *Lld = Args.MakeArgString(getToolChain().GetProgramPath("lld"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Lld, LldArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Lld, LldArgs, Inputs));
 }
 
 // Construct a clang-offload-bundler command to bundle code objects for
 // different GPU's into a HIP fat binary.
 void AMDGCN::constructHIPFatbinCommand(Compilation &C, const JobAction &JA,
                   StringRef OutputFileName, const InputInfoList &Inputs,
                   const llvm::opt::ArgList &Args, const Tool& T) {
   // Construct clang-offload-bundler command to bundle object files for
void AMDGCN::constructHIPFatbinCommand(Compilation &C, const JobAction &JA,
   BundlerArgs.push_back(Args.MakeArgString(BundlerInputArg));
 
   auto BundlerOutputArg = Args.MakeArgString(
       std::string("-outputs=").append(std::string(OutputFileName)));
   BundlerArgs.push_back(BundlerOutputArg);
 
   const char *Bundler = Args.MakeArgString(
       T.getToolChain().GetProgramPath("clang-offload-bundler"));
-  C.addCommand(std::make_unique<Command>(JA, T, Bundler, BundlerArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, T, ResponseFileSupport::None(),
+                                         Bundler, BundlerArgs, Inputs));
 }
 
 /// Add Generated HIP Object File which has device images embedded into the
 /// host to the argument list for linking. Using MC directives, embed the
 /// device code and also define symbols required by the code generation so that
 /// the image can be retrieved at runtime.
 void AMDGCN::Linker::constructGenerateObjFileFromHIPFatBinary(
     Compilation &C, const InputInfo &Output,
void AMDGCN::Linker::constructGenerateObjFileFromHIPFatBinary(
   }
 
   Objf << ObjBuffer;
 
   ArgStringList McArgs{"-triple", Args.MakeArgString(TC.getTripleString()),
                        "-o",      Output.getFilename(),
                        McinFile,  "--filetype=obj"};
   const char *Mc = Args.MakeArgString(TC.GetProgramPath("llvm-mc"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Mc, McArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Mc, McArgs, Inputs));
 }
 
 // For amdgcn the inputs of the linker job are device bitcode and output is
 // object file. It calls llvm-link, opt, llc, then lld steps.
 void AMDGCN::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                    const InputInfo &Output,
                                    const InputInfoList &Inputs,
                                    const ArgList &Args,

clang/lib/Driver/ToolChains/Hexagon.h

 
 namespace clang {
 namespace driver {
 namespace tools {
 namespace hexagon {
 // For Hexagon, we do not need to instantiate tools for PreProcess, PreCompile
 // and Compile.
 // We simply use "clang -cc1" for those actions.
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
   Assembler(const ToolChain &TC)
-      : GnuTool("hexagon::Assembler", "hexagon-as", TC) {}
+      : Tool("hexagon::Assembler", "hexagon-as", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void RenderExtraToolArgs(const JobAction &JA,
                            llvm::opt::ArgStringList &CmdArgs) const;
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("hexagon::Linker", "hexagon-ld", TC) {}
+  Linker(const ToolChain &TC) : Tool("hexagon::Linker", "hexagon-ld", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   virtual void RenderExtraToolArgs(const JobAction &JA,
                                    llvm::opt::ArgStringList &CmdArgs) const;
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,

clang/lib/Driver/ToolChains/Hexagon.cpp

if (II.isFilename())
       CmdArgs.push_back(II.getFilename());
     else
       // Don't render as input, we need gcc to do the translations.
       // FIXME: What is this?
       II.getInputArg().render(Args, CmdArgs);
   }
 
   auto *Exec = Args.MakeArgString(HTC.GetProgramPath(AsName));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void hexagon::Linker::RenderExtraToolArgs(const JobAction &JA,
                                           ArgStringList &CmdArgs) const {
 }
 
 static void
 constructHexagonLinkArgs(Compilation &C, const JobAction &JA,
void hexagon::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                    const char *LinkingOutput) const {
   auto &HTC = static_cast<const toolchains::HexagonToolChain&>(getToolChain());
 
   ArgStringList CmdArgs;
   constructHexagonLinkArgs(C, JA, HTC, Output, Inputs, Args, CmdArgs,
                            LinkingOutput);
 
   const char *Exec = Args.MakeArgString(HTC.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 // Hexagon tools end.
 
 /// Hexagon Toolchain
 
 std::string HexagonToolChain::getHexagonTargetDir(
       const std::string &InstalledDir,
       const SmallVectorImpl<std::string> &PrefixDirs) const {

clang/lib/Driver/ToolChains/InterfaceStubs.cpp

for (const auto &Input : Inputs) {
     if (!Input.isFilename())
       continue;
     SmallString<128> InputFilename(Input.getFilename());
     if (Input.getType() == types::TY_Object)
       llvm::sys::path::replace_extension(InputFilename, ".ifs");
     CmdArgs.push_back(Args.MakeArgString(InputFilename.c_str()));
   }
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Merger),
-                                         CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Args.MakeArgString(Merger), CmdArgs,
+                                         Inputs));
 }
 } // namespace ifstool
 } // namespace tools
 } // namespace driver
 } // namespace clang

clang/lib/Driver/ToolChains/MSP430.h

private:
   std::string computeSysRoot() const override;
 };
 
 } // end namespace toolchains
 
 namespace tools {
 namespace msp430 {
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC)
-      : GnuTool("MSP430::Linker", "msp430-elf-ld", TC) {}
+  Linker(const ToolChain &TC) : Tool("MSP430::Linker", "msp430-elf-ld", TC) {}
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 void getMSP430TargetFeatures(const Driver &D, const llvm::opt::ArgList &Args,
                              std::vector<llvm::StringRef> &Features);
 } // end namespace msp430
 } // end namespace tools
 } // end namespace driver
 } // end namespace clang
 
 #endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MSP430_H

clang/lib/Driver/ToolChains/MSP430.cpp

void msp430::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   CmdArgs.push_back("--end-group");
 
   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
   }
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Linker),
-                                          CmdArgs, Inputs));
+  C.addCommand(
+      std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
+                                Args.MakeArgString(Linker), CmdArgs, Inputs));
 }

clang/lib/Driver/ToolChains/MSVC.h

 namespace clang {
 namespace driver {
 namespace tools {
 
 /// Visual studio tools.
 namespace visualstudio {
 class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC)
-      : Tool("visualstudio::Linker", "linker", TC, RF_Full,
-             llvm::sys::WEM_UTF16) {}
+  Linker(const ToolChain &TC) : Tool("visualstudio::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY Compiler : public Tool {
 public:
   Compiler(const ToolChain &TC)
-      : Tool("visualstudio::Compiler", "compiler", TC, RF_Full,
-             llvm::sys::WEM_UTF16) {}
+      : Tool("visualstudio::Compiler", "compiler", TC) {}
 
   bool hasIntegratedAssembler() const override { return true; }
   bool hasIntegratedCPP() const override { return true; }
   bool isLinkJob() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,

clang/lib/Driver/ToolChains/MSVC.cpp

if (TC.getIsVS2017OrNewer() &&
       }
     }
   SkipSettingEnvironment:;
 #endif
   } else {
     linkPath = TC.GetProgramPath(Linker.str().c_str());
   }
 
-  auto LinkCmd = std::make_unique<Command>(
-      JA, *this, Args.MakeArgString(linkPath), CmdArgs, Inputs);
+  auto LinkCmd =
+      std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileUTF16(),
+                                Args.MakeArgString(linkPath), CmdArgs, Inputs);
   if (!Environment.empty())
     LinkCmd->setEnvironment(Environment);
   C.addCommand(std::move(LinkCmd));
 }
 
 void visualstudio::Compiler::ConstructJob(Compilation &C, const JobAction &JA,
                                           const InputInfo &Output,
                                           const InputInfoList &Inputs,
std::unique_ptr<Command> visualstudio::Compiler::GetCommand(
 
   // Output filename.
   assert(Output.getType() == types::TY_Object);
   const char *Fo =
       Args.MakeArgString(std::string("/Fo") + Output.getFilename());
   CmdArgs.push_back(Fo);
 
   std::string Exec = FindVisualStudioExecutable(getToolChain(), "cl.exe");
-  return std::make_unique<Command>(JA, *this, Args.MakeArgString(Exec),
-                                    CmdArgs, Inputs);
+  return std::make_unique<Command>(JA, *this,
+                                   ResponseFileSupport::AtFileUTF16(),
+                                   Args.MakeArgString(Exec), CmdArgs, Inputs);
 }
 
 MSVCToolChain::MSVCToolChain(const Driver &D, const llvm::Triple &Triple,
                              const ArgList &Args)
     : ToolChain(D, Triple, Args), CudaInstallation(D, Triple, Args),
       RocmInstallation(D, Triple, Args) {
   getProgramPaths().push_back(getDriver().getInstalledDir());
   if (getDriver().getInstalledDir() != getDriver().Dir)

clang/lib/Driver/ToolChains/MinGW.h

 //===--- MinGW.h - MinGW ToolChain Implementations --------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MINGW_H
 #define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MINGW_H
 
 #include "Cuda.h"
 #include "Gnu.h"
 #include "clang/Driver/Tool.h"
 #include "clang/Driver/ToolChain.h"
+#include "llvm/Support/ErrorOr.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 
 /// MinGW -- Directly call GNU Binutils assembler and linker
 namespace MinGW {
 class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
   Assembler(const ToolChain &TC) : Tool("MinGW::Assemble", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC)
-      : Tool("MinGW::Linker", "linker", TC, Tool::RF_Full) {}
+  Linker(const ToolChain &TC) : Tool("MinGW::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/MinGW.cpp

void tools::MinGW::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 
   if (Args.hasArg(options::OPT_gsplit_dwarf))
     SplitDebugInfo(getToolChain(), C, *this, JA, Args, Output,
                    SplitDebugName(Args, Inputs[0], Output));
 }
 
 void tools::MinGW::Linker::AddLibGCC(const ArgList &Args,
                                      ArgStringList &CmdArgs) const {
if (!Args.hasArg(options::OPT_nostdlib)) {
     if (!Args.hasArg(options::OPT_nostartfiles)) {
       // Add crtfastmath.o if available and fast math is enabled.
       TC.addFastMathRuntimeIfAvailable(Args, CmdArgs);
 
       CmdArgs.push_back(Args.MakeArgString(TC.GetFilePath("crtend.o")));
     }
   }
   const char *Exec = Args.MakeArgString(TC.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
 }
 
 // Simplified from Generic_GCC::GCCInstallationDetector::ScanLibDirForGCCTriple.
 static bool findGccVersion(StringRef LibDir, std::string &GccLibDir,
                            std::string &Ver) {
   auto Version = toolchains::Generic_GCC::GCCVersion::Parse("0.0.0");
   std::error_code EC;
   for (llvm::sys::fs::directory_iterator LI(LibDir, EC), LE; !EC && LI != LE;

clang/lib/Driver/ToolChains/Minix.h

 #include "clang/Driver/Tool.h"
 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 /// minix -- Directly call GNU Binutils assembler and linker
 namespace minix {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
-  Assembler(const ToolChain &TC)
-      : GnuTool("minix::Assembler", "assembler", TC) {}
+  Assembler(const ToolChain &TC) : Tool("minix::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("minix::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("minix::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/Minix.cpp

void tools::minix::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void tools::minix::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                  const InputInfo &Output,
                                  const InputInfoList &Inputs,
                                  const ArgList &Args,
                                  const char *LinkingOutput) const {
   const Driver &D = getToolChain().getDriver();
if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
     CmdArgs.push_back("-lc");
     CmdArgs.push_back("-lCompilerRT-Generic");
     CmdArgs.push_back("-L/usr/pkg/compiler-rt/lib");
     CmdArgs.push_back(
         Args.MakeArgString(getToolChain().GetFilePath("crtend.o")));
   }
 
   const char *Exec = Args.MakeArgString(getToolChain().GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 /// Minix - Minix tool chain which can call as(1) and ld(1) directly.
 
 toolchains::Minix::Minix(const Driver &D, const llvm::Triple &Triple,
                          const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   getFilePaths().push_back(getDriver().Dir + "/../lib");

clang/lib/Driver/ToolChains/Myriad.h

 };
 } // end namespace SHAVE
 
 /// The Myriad toolchain uses tools that are in two different namespaces.
 /// The Compiler and Assembler as defined above are in the SHAVE namespace,
 /// whereas the linker, which accepts code for a mixture of Sparc and SHAVE,
 /// is in the Myriad namespace.
 namespace Myriad {
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("shave::Linker", "ld", TC) {}
+  Linker(const ToolChain &TC) : Tool("shave::Linker", "ld", TC) {}
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 } // end namespace Myriad

clang/lib/Driver/ToolChains/Myriad.cpp

void tools::SHAVE::Compiler::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   CmdArgs.push_back(II.getFilename());
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   std::string Exec =
       Args.MakeArgString(getToolChain().GetProgramPath("moviCompile"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Exec),
-                                          CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Args.MakeArgString(Exec), CmdArgs,
+                                         Inputs));
 }
 
 void tools::SHAVE::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
                                            const InputInfo &Output,
                                            const InputInfoList &Inputs,
                                            const ArgList &Args,
                                            const char *LinkingOutput) const {
   ArgStringList CmdArgs;
CmdArgs.push_back(
         Args.MakeArgString(std::string("-i:") + A->getValue(0)));
   }
   CmdArgs.push_back(II.getFilename());
   CmdArgs.push_back(
       Args.MakeArgString(std::string("-o:") + Output.getFilename()));
 
   std::string Exec =
       Args.MakeArgString(getToolChain().GetProgramPath("moviAsm"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Exec),
-                                          CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Args.MakeArgString(Exec), CmdArgs,
+                                         Inputs));
 }
 
 void tools::Myriad::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                          const InputInfo &Output,
                                          const InputInfoList &Inputs,
                                          const ArgList &Args,
                                          const char *LinkingOutput) const {
   const auto &TC =
void tools::Myriad::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   }
   if (UseStartfiles) {
     CmdArgs.push_back(Args.MakeArgString(TC.GetFilePath("crtend.o")));
     CmdArgs.push_back(Args.MakeArgString(TC.GetFilePath("crtn.o")));
   }
 
   std::string Exec =
       Args.MakeArgString(TC.GetProgramPath("sparc-myriad-rtems-ld"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Exec),
-                                          CmdArgs, Inputs));
+  C.addCommand(
+      std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
+                                Args.MakeArgString(Exec), CmdArgs, Inputs));
 }
 
 MyriadToolChain::MyriadToolChain(const Driver &D, const llvm::Triple &Triple,
                                  const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   // If a target of 'sparc-myriad-elf' is specified to clang, it wants to use
   // 'sparc-myriad--elf' (note the unknown OS) as the canonical triple.
   // This won't work to find gcc. Instead we give the installation detector an

clang/lib/Driver/ToolChains/NaCl.h

public:
   AssemblerARM(const ToolChain &TC) : gnutools::Assembler(TC) {}
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("NaCl::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("NaCl::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/NaCl.cpp

if (!Args.hasArg(options::OPT_nostartfiles)) {
         crtend = "crtend.o";
 
       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
       CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
     }
   }
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 /// NaCl Toolchain
 NaClToolChain::NaClToolChain(const Driver &D, const llvm::Triple &Triple,
                              const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
 
   // Remove paths added by Generic_GCC. NaCl Toolchain cannot use the

clang/lib/Driver/ToolChains/NetBSD.h

 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 
 /// netbsd -- Directly call GNU Binutils assembler and linker
 namespace netbsd {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
-  Assembler(const ToolChain &TC)
-      : GnuTool("netbsd::Assembler", "assembler", TC) {}
+  Assembler(const ToolChain &TC) : Tool("netbsd::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("netbsd::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("netbsd::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/NetBSD.cpp

void netbsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString((getToolChain().GetProgramPath("as")));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void netbsd::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                   const InputInfo &Output,
                                   const InputInfoList &Inputs,
                                   const ArgList &Args,
                                   const char *LinkingOutput) const {
   const toolchains::NetBSD &ToolChain =
else
       CmdArgs.push_back(
           Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
   }
 
   ToolChain.addProfileRTLibs(Args, CmdArgs);
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 /// NetBSD - NetBSD tool chain which can call as(1) and ld(1) directly.
 
 NetBSD::NetBSD(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   if (!Args.hasArg(options::OPT_nostdlib)) {
     // When targeting a 32-bit platform, try the special directory used on

clang/lib/Driver/ToolChains/OpenBSD.h

 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 
 /// openbsd -- Directly call GNU Binutils assembler and linker
 namespace openbsd {
-class LLVM_LIBRARY_VISIBILITY Assembler : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Assembler : public Tool {
 public:
   Assembler(const ToolChain &TC)
-      : GnuTool("openbsd::Assembler", "assembler", TC) {}
+      : Tool("openbsd::Assembler", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("openbsd::Linker", "linker", TC) {}
+  Linker(const ToolChain &TC) : Tool("openbsd::Linker", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;

clang/lib/Driver/ToolChains/OpenBSD.cpp

void openbsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 void openbsd::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                    const InputInfo &Output,
                                    const InputInfoList &Inputs,
                                    const ArgList &Args,
                                    const char *LinkingOutput) const {
   const toolchains::OpenBSD &ToolChain =
if (!Args.hasArg(options::OPT_shared))
       crtend = "crtend.o";
     else
       crtend = "crtendS.o";
 
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
   }
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Exec, CmdArgs, Inputs));
 }
 
 SanitizerMask OpenBSD::getSupportedSanitizers() const {
   const bool IsX86 = getTriple().getArch() == llvm::Triple::x86;
   const bool IsX86_64 = getTriple().getArch() == llvm::Triple::x86_64;
 
   // For future use, only UBsan at the moment
   SanitizerMask Res = ToolChain::getSupportedSanitizers();

clang/lib/Driver/ToolChains/PS4CPU.h

 
 void addProfileRTArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
                       llvm::opt::ArgStringList &CmdArgs);
 
 void addSanitizerArgs(const ToolChain &TC, llvm::opt::ArgStringList &CmdArgs);
 
 class LLVM_LIBRARY_VISIBILITY Assemble : public Tool {
 public:
-  Assemble(const ToolChain &TC)
-      : Tool("PS4cpu::Assemble", "assembler", TC, RF_Full) {}
+  Assemble(const ToolChain &TC) : Tool("PS4cpu::Assemble", "assembler", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output,
                     const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY Link : public Tool {
 public:
-  Link(const ToolChain &TC) : Tool("PS4cpu::Link", "linker", TC, RF_Full) {}
+  Link(const ToolChain &TC) : Tool("PS4cpu::Link", "linker", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
 
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output,
                     const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,

clang/lib/Driver/ToolChains/PS4CPU.cpp

void tools::PS4cpu::Assemble::ConstructJob(Compilation &C, const JobAction &JA,
 
   assert(Inputs.size() == 1 && "Unexpected number of inputs.");
   const InputInfo &Input = Inputs[0];
   assert(Input.isFilename() && "Invalid input.");
   CmdArgs.push_back(Input.getFilename());
 
   const char *Exec =
       Args.MakeArgString(getToolChain().GetProgramPath("orbis-as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
 }
 
 static void AddPS4SanitizerArgs(const ToolChain &TC, ArgStringList &CmdArgs) {
   const SanitizerArgs &SanArgs = TC.getSanitizerArgs();
   if (SanArgs.needsUbsanRt()) {
     CmdArgs.push_back("-lSceDbgUBSanitizer_stub_weak");
   }
   if (SanArgs.needsAsanRt()) {
void tools::PS4cpu::Link::ConstructJob(Compilation &C, const JobAction &JA,
   if (Args.hasArg(options::OPT_fuse_ld_EQ)) {
     D.Diag(diag::err_drv_unsupported_opt_for_target)
         << "-fuse-ld" << getToolChain().getTriple().str();
   }
 
   const char *Exec =
       Args.MakeArgString(ToolChain.GetProgramPath("orbis-ld"));
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF8(), Exec, CmdArgs, Inputs));
 }
 
 toolchains::PS4CPU::PS4CPU(const Driver &D, const llvm::Triple &Triple,
                            const ArgList &Args)
     : Generic_ELF(D, Triple, Args) {
   if (Args.hasArg(clang::driver::options::OPT_static))
     D.Diag(clang::diag::err_drv_unsupported_opt_for_target) << "-static"
                                                             << "PS4";

clang/lib/Driver/ToolChains/RISCVToolchain.h

 private:
   std::string computeSysRoot() const override;
 };
 
 } // end namespace toolchains
 
 namespace tools {
 namespace RISCV {
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  Linker(const ToolChain &TC) : GnuTool("RISCV::Linker", "ld", TC) {}
+  Linker(const ToolChain &TC) : Tool("RISCV::Linker", "ld", TC) {}
   bool hasIntegratedCPP() const override { return false; }
   bool isLinkJob() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
 } // end namespace RISCV
 } // end namespace tools
 
 } // end namespace driver
 } // end namespace clang
 
 #endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_RISCVTOOLCHAIN_H

clang/lib/Driver/ToolChains/RISCVToolchain.cpp

if (!Args.hasArg(options::OPT_nostdlib) &&
     AddRunTimeLibs(ToolChain, ToolChain.getDriver(), CmdArgs, Args);
   }
 
   if (WantCRTs)
     CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
-  C.addCommand(std::make_unique<Command>(JA, *this, Args.MakeArgString(Linker),
-                                          CmdArgs, Inputs));
+  C.addCommand(
+      std::make_unique<Command>(JA, *this, ResponseFileSupport::AtFileCurCP(),
+                                Args.MakeArgString(Linker), CmdArgs, Inputs));
 }
 // RISCV tools end.

clang/lib/Driver/ToolChains/Solaris.cpp

void solaris::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("as"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void solaris::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                    const InputInfo &Output,
                                    const InputInfoList &Inputs,
                                    const ArgList &Args,
                                    const char *LinkingOutput) const {
   ArgStringList CmdArgs;
if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) {
     CmdArgs.push_back(
         Args.MakeArgString(getToolChain().GetFilePath("crtend.o")));
   }
   CmdArgs.push_back(Args.MakeArgString(getToolChain().GetFilePath("crtn.o")));
 
   getToolChain().addProfileRTLibs(Args, CmdArgs);
 
   const char *Exec = Args.MakeArgString(getToolChain().GetLinkerPath());
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 static StringRef getSolarisLibSuffix(const llvm::Triple &Triple) {
   switch (Triple.getArch()) {
   case llvm::Triple::x86:
   case llvm::Triple::sparc:
     break;
   case llvm::Triple::x86_64:

clang/lib/Driver/ToolChains/WebAssembly.h

 #include "clang/Driver/Tool.h"
 #include "clang/Driver/ToolChain.h"
 
 namespace clang {
 namespace driver {
 namespace tools {
 namespace wasm {
 
-class LLVM_LIBRARY_VISIBILITY Linker : public GnuTool {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
 public:
-  explicit Linker(const ToolChain &TC)
-      : GnuTool("wasm::Linker", "linker", TC) {}
+  explicit Linker(const ToolChain &TC) : Tool("wasm::Linker", "linker", TC) {}
   bool isLinkJob() const override { return true; }
   bool hasIntegratedCPP() const override { return false; }
   std::string getLinkerPath(const llvm::opt::ArgList &Args) const;
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };

clang/lib/Driver/ToolChains/WebAssembly.cpp

if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
 
     CmdArgs.push_back("-lc");
     AddRunTimeLibs(ToolChain, ToolChain.getDriver(), CmdArgs, Args);
   }
 
   CmdArgs.push_back("-o");
   CmdArgs.push_back(Output.getFilename());
 
-  C.addCommand(std::make_unique<Command>(JA, *this, Linker, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileCurCP(), Linker, CmdArgs, Inputs));
 
   // When optimizing, if wasm-opt is available, run it.
   if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
     auto WasmOptPath = getToolChain().GetProgramPath("wasm-opt");
     if (WasmOptPath != "wasm-opt") {
       StringRef OOpt = "s";
       if (A->getOption().matches(options::OPT_O4) ||
           A->getOption().matches(options::OPT_Ofast))
         OOpt = "4";
       else if (A->getOption().matches(options::OPT_O0))
         OOpt = "0";
       else if (A->getOption().matches(options::OPT_O))
         OOpt = A->getValue();
 
       if (OOpt != "0") {
         const char *WasmOpt = Args.MakeArgString(WasmOptPath);
         ArgStringList CmdArgs;
         CmdArgs.push_back(Output.getFilename());
         CmdArgs.push_back(Args.MakeArgString(llvm::Twine("-O") + OOpt));
         CmdArgs.push_back("-o");
         CmdArgs.push_back(Output.getFilename());
-        C.addCommand(std::make_unique<Command>(JA, *this, WasmOpt, CmdArgs, Inputs));
+        C.addCommand(std::make_unique<Command>(
+            JA, *this, ResponseFileSupport::AtFileCurCP(), WasmOpt, CmdArgs,
+            Inputs));
       }
     }
   }
 }
 
 /// Given a base library directory, append path components to form the
 /// LTO directory.
 static std::string AppendLTOLibDir(const std::string &Dir) {

clang/lib/Driver/ToolChains/XCore.cpp

if (Args.hasFlag(options::OPT_fverbose_asm, options::OPT_fno_verbose_asm,
     CmdArgs.push_back("-fverbose-asm");
 
   Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
 
   for (const auto &II : Inputs)
     CmdArgs.push_back(II.getFilename());
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("xcc"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 void tools::XCore::Linker::ConstructJob(Compilation &C, const JobAction &JA,
                                         const InputInfo &Output,
                                         const InputInfoList &Inputs,
                                         const ArgList &Args,
                                         const char *LinkingOutput) const {
   ArgStringList CmdArgs;
void tools::XCore::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   // Pass -fexceptions through to the linker if it was present.
   if (Args.hasFlag(options::OPT_fexceptions, options::OPT_fno_exceptions,
                    false))
     CmdArgs.push_back("-fexceptions");
 
   AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("xcc"));
-  C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
+  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),
+                                         Exec, CmdArgs, Inputs));
 }
 
 /// XCore tool chain
 XCoreToolChain::XCoreToolChain(const Driver &D, const llvm::Triple &Triple,
                                const ArgList &Args)
     : ToolChain(D, Triple, Args) {
   // ProgramPaths are found via 'PATH' environment variable.
 }