CMake/Source/cmMakefile.cxx

/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   file Copyright.txt or https://cmake.org/licensing for details.  */
#include "cmMakefile.h"

#include "cmsys/FStream.hxx"
#include "cmsys/RegularExpression.hxx"
#include <algorithm>
#include <assert.h>
#include <ctype.h>
#include <iterator>
#include <memory> // IWYU pragma: keep
#include <sstream>
#include <stdlib.h>
#include <string.h>
#include <utility>

#include "cmAlgorithms.h"
#include "cmCommand.h"
#include "cmCommandArgumentParserHelper.h"
#include "cmCustomCommand.h"
#include "cmCustomCommandLines.h"
#include "cmExecutionStatus.h"
#include "cmExpandedCommandArgument.h"
#include "cmFileLockPool.h"
#include "cmFunctionBlocker.h"
#include "cmGeneratorExpression.h"
#include "cmGeneratorExpressionEvaluationFile.h"
#include "cmGlobalGenerator.h"
#include "cmInstallGenerator.h" // IWYU pragma: keep
#include "cmListFileCache.h"
#include "cmSourceFile.h"
#include "cmSourceFileLocation.h"
#include "cmState.h"
#include "cmStateDirectory.h"
#include "cmStateTypes.h"
#include "cmSystemTools.h"
#include "cmTargetLinkLibraryType.h"
#include "cmTest.h"
#include "cmTestGenerator.h" // IWYU pragma: keep
#include "cmVersion.h"
#include "cmWorkingDirectory.h"
#include "cm_sys_stat.h"
#include "cmake.h"

#ifdef CMAKE_BUILD_WITH_CMAKE
#include "cmVariableWatch.h"
#endif

class cmMessenger;

// default is not to be building executables
cmMakefile::cmMakefile(cmGlobalGenerator* globalGenerator,
                       cmStateSnapshot const& snapshot)
  : GlobalGenerator(globalGenerator)
  , StateSnapshot(snapshot)
  , Backtrace(snapshot)
{
  this->IsSourceFileTryCompile = false;

  this->WarnUnused = this->GetCMakeInstance()->GetWarnUnused();
  this->CheckSystemVars = this->GetCMakeInstance()->GetCheckSystemVars();

  this->SuppressWatches = false;

  // Setup the default include complaint regular expression (match nothing).
  this->ComplainFileRegularExpression = "^$";

  this->DefineFlags = " ";

  this->cmDefineRegex.compile("#([ \t]*)cmakedefine[ \t]+([A-Za-z_0-9]*)");
  this->cmDefine01Regex.compile("#([ \t]*)cmakedefine01[ \t]+([A-Za-z_0-9]*)");
  this->cmAtVarRegex.compile("(@[A-Za-z_0-9/.+-]+@)");
  this->cmNamedCurly.compile("^[A-Za-z0-9/_.+-]+{");

  this->StateSnapshot =
    this->StateSnapshot.GetState()->CreatePolicyScopeSnapshot(
      this->StateSnapshot);

  // Enter a policy level for this directory.
  this->PushPolicy();

  // push empty loop block
  this->PushLoopBlockBarrier();

  // By default the check is not done.  It is enabled by
  // cmListFileCache in the top level if necessary.
  this->CheckCMP0000 = false;

#if defined(CMAKE_BUILD_WITH_CMAKE)
  this->AddSourceGroup("", "^.*$");
  this->AddSourceGroup("Source Files", CM_SOURCE_REGEX);
  this->AddSourceGroup("Header Files", CM_HEADER_REGEX);
  this->AddSourceGroup("CMake Rules", "\\.rule$");
  this->AddSourceGroup("Resources", CM_RESOURCE_REGEX);
  this->AddSourceGroup("Object Files", "\\.(lo|o|obj)$");

  this->ObjectLibrariesSourceGroupIndex = this->SourceGroups.size();
  this->SourceGroups.push_back(
    cmSourceGroup("Object Libraries", "^MATCH_NO_SOURCES$"));
#endif
}

cmMakefile::~cmMakefile()
{
  cmDeleteAll(this->InstallGenerators);
  cmDeleteAll(this->TestGenerators);
  cmDeleteAll(this->SourceFiles);
  cmDeleteAll(this->Tests);
  cmDeleteAll(this->ImportedTargetsOwned);
  cmDeleteAll(this->FinalPassCommands);
  cmDeleteAll(this->FunctionBlockers);
  cmDeleteAll(this->EvaluationFiles);
}

void cmMakefile::IssueMessage(cmake::MessageType t,
                              std::string const& text) const
{
  if (!this->ExecutionStatusStack.empty()) {
    if ((t == cmake::FATAL_ERROR) || (t == cmake::INTERNAL_ERROR)) {
      this->ExecutionStatusStack.back()->SetNestedError();
    }
  }
  this->GetCMakeInstance()->IssueMessage(t, text, this->GetBacktrace());
}

bool cmMakefile::CheckCMP0037(std::string const& targetName,
                              cmStateEnums::TargetType targetType) const
{
  cmake::MessageType messageType = cmake::AUTHOR_WARNING;
  std::ostringstream e;
  bool issueMessage = false;
  switch (this->GetPolicyStatus(cmPolicies::CMP0037)) {
    case cmPolicies::WARN:
      if (targetType != cmStateEnums::INTERFACE_LIBRARY) {
        e << cmPolicies::GetPolicyWarning(cmPolicies::CMP0037) << "\n";
        issueMessage = true;
      }
      CM_FALLTHROUGH;
    case cmPolicies::OLD:
      break;
    case cmPolicies::NEW:
    case cmPolicies::REQUIRED_IF_USED:
    case cmPolicies::REQUIRED_ALWAYS:
      issueMessage = true;
      messageType = cmake::FATAL_ERROR;
      break;
  }
  if (issueMessage) {
    e << "The target name \"" << targetName
      << "\" is reserved or not valid for certain "
         "CMake features, such as generator expressions, and may result "
         "in undefined behavior.";
    this->IssueMessage(messageType, e.str());

    if (messageType == cmake::FATAL_ERROR) {
      return false;
    }
  }
  return true;
}

cmStringRange cmMakefile::GetIncludeDirectoriesEntries() const
{
  return this->StateSnapshot.GetDirectory().GetIncludeDirectoriesEntries();
}

cmBacktraceRange cmMakefile::GetIncludeDirectoriesBacktraces() const
{
  return this->StateSnapshot.GetDirectory()
    .GetIncludeDirectoriesEntryBacktraces();
}

cmStringRange cmMakefile::GetCompileOptionsEntries() const
{
  return this->StateSnapshot.GetDirectory().GetCompileOptionsEntries();
}

cmBacktraceRange cmMakefile::GetCompileOptionsBacktraces() const
{
  return this->StateSnapshot.GetDirectory().GetCompileOptionsEntryBacktraces();
}

cmStringRange cmMakefile::GetCompileDefinitionsEntries() const
{
  return this->StateSnapshot.GetDirectory().GetCompileDefinitionsEntries();
}

cmBacktraceRange cmMakefile::GetCompileDefinitionsBacktraces() const
{
  return this->StateSnapshot.GetDirectory()
    .GetCompileDefinitionsEntryBacktraces();
}

cmListFileBacktrace cmMakefile::GetBacktrace() const
{
  return this->Backtrace;
}

cmListFileBacktrace cmMakefile::GetBacktrace(cmCommandContext const& cc) const
{
  cmListFileContext lfc;
  lfc.Name = cc.Name;
  lfc.Line = cc.Line;
  lfc.FilePath = this->StateSnapshot.GetExecutionListFile();
  return this->Backtrace.Push(lfc);
}

cmListFileContext cmMakefile::GetExecutionContext() const
{
  cmListFileContext const& cur = this->Backtrace.Top();
  cmListFileContext lfc;
  lfc.Name = cur.Name;
  lfc.Line = cur.Line;
  lfc.FilePath = this->StateSnapshot.GetExecutionListFile();
  return lfc;
}

void cmMakefile::PrintCommandTrace(const cmListFileFunction& lff) const
{
  // Check if current file in the list of requested to trace...
  std::vector<std::string> const& trace_only_this_files =
    this->GetCMakeInstance()->GetTraceSources();
  std::string const& full_path = this->GetExecutionFilePath();
  std::string const& only_filename = cmSystemTools::GetFilenameName(full_path);
  bool trace = trace_only_this_files.empty();
  if (!trace) {
    for (std::vector<std::string>::const_iterator i =
           trace_only_this_files.begin();
         !trace && i != trace_only_this_files.end(); ++i) {
      std::string::size_type const pos = full_path.rfind(*i);
      trace = (pos != std::string::npos) &&
        ((pos + i->size()) == full_path.size()) &&
        (only_filename == cmSystemTools::GetFilenameName(*i));
    }
    // Do nothing if current file wasn't requested for trace...
    if (!trace) {
      return;
    }
  }

  std::ostringstream msg;
  msg << full_path << "(" << lff.Line << "):  ";
  msg << lff.Name << "(";
  bool expand = this->GetCMakeInstance()->GetTraceExpand();
  std::string temp;
  for (cmListFileArgument const& arg : lff.Arguments) {
    if (expand) {
      temp = arg.Value;
      this->ExpandVariablesInString(temp);
      msg << temp;
    } else {
      msg << arg.Value;
    }
    msg << " ";
  }
  msg << ")";
  cmSystemTools::Message(msg.str().c_str());
}

// Helper class to make sure the call stack is valid.
class cmMakefileCall
{
public:
  cmMakefileCall(cmMakefile* mf, cmCommandContext const& cc,
                 cmExecutionStatus& status)
    : Makefile(mf)
  {
    cmListFileContext const& lfc = cmListFileContext::FromCommandContext(
      cc, this->Makefile->StateSnapshot.GetExecutionListFile());
    this->Makefile->Backtrace = this->Makefile->Backtrace.Push(lfc);
    this->Makefile->ExecutionStatusStack.push_back(&status);
  }

  ~cmMakefileCall()
  {
    this->Makefile->ExecutionStatusStack.pop_back();
    this->Makefile->Backtrace = this->Makefile->Backtrace.Pop();
  }

private:
  cmMakefile* Makefile;
};

bool cmMakefile::ExecuteCommand(const cmListFileFunction& lff,
                                cmExecutionStatus& status)
{
  bool result = true;

  // quick return if blocked
  if (this->IsFunctionBlocked(lff, status)) {
    // No error.
    return result;
  }

  std::string name = lff.Name;

  // Place this call on the call stack.
  cmMakefileCall stack_manager(this, lff, status);
  static_cast<void>(stack_manager);

  // Lookup the command prototype.
  if (cmCommand* proto = this->GetState()->GetCommand(name)) {
    // Clone the prototype.
    std::unique_ptr<cmCommand> pcmd(proto->Clone());
    pcmd->SetMakefile(this);

    // Decide whether to invoke the command.
    if (!cmSystemTools::GetFatalErrorOccured()) {
      // if trace is enabled, print out invoke information
      if (this->GetCMakeInstance()->GetTrace()) {
        this->PrintCommandTrace(lff);
      }
      // Try invoking the command.
      bool invokeSucceeded = pcmd->InvokeInitialPass(lff.Arguments, status);
      bool hadNestedError = status.GetNestedError();
      if (!invokeSucceeded || hadNestedError) {
        if (!hadNestedError) {
          // The command invocation requested that we report an error.
          std::string const error = name + " " + pcmd->GetError();
          this->IssueMessage(cmake::FATAL_ERROR, error);
        }
        result = false;
        if (this->GetCMakeInstance()->GetWorkingMode() != cmake::NORMAL_MODE) {
          cmSystemTools::SetFatalErrorOccured();
        }
      } else if (pcmd->HasFinalPass()) {
        // use the command
        this->FinalPassCommands.push_back(pcmd.release());
      }
    }
  } else {
    if (!cmSystemTools::GetFatalErrorOccured()) {
      std::string error = "Unknown CMake command \"";
      error += lff.Name;
      error += "\".";
      this->IssueMessage(cmake::FATAL_ERROR, error);
      result = false;
      cmSystemTools::SetFatalErrorOccured();
    }
  }

  return result;
}

class cmMakefile::IncludeScope
{
public:
  IncludeScope(cmMakefile* mf, std::string const& filenametoread,
               bool noPolicyScope);
  ~IncludeScope();
  void Quiet() { this->ReportError = false; }

private:
  cmMakefile* Makefile;
  bool NoPolicyScope;
  bool CheckCMP0011;
  bool ReportError;
  void EnforceCMP0011();
};

cmMakefile::IncludeScope::IncludeScope(cmMakefile* mf,
                                       std::string const& filenametoread,
                                       bool noPolicyScope)
  : Makefile(mf)
  , NoPolicyScope(noPolicyScope)
  , CheckCMP0011(false)
  , ReportError(true)
{
  this->Makefile->Backtrace = this->Makefile->Backtrace.Push(filenametoread);

  this->Makefile->PushFunctionBlockerBarrier();

  this->Makefile->StateSnapshot =
    this->Makefile->GetState()->CreateIncludeFileSnapshot(
      this->Makefile->StateSnapshot, filenametoread);
  if (!this->NoPolicyScope) {
    // Check CMP0011 to determine the policy scope type.
    switch (this->Makefile->GetPolicyStatus(cmPolicies::CMP0011)) {
      case cmPolicies::WARN:
        // We need to push a scope to detect whether the script sets
        // any policies that would affect the includer and therefore
        // requires a warning.  We use a weak scope to simulate OLD
        // behavior by allowing policy changes to affect the includer.
        this->Makefile->PushPolicy(true);
        this->CheckCMP0011 = true;
        break;
      case cmPolicies::OLD:
        // OLD behavior is to not push a scope at all.
        this->NoPolicyScope = true;
        break;
      case cmPolicies::REQUIRED_IF_USED:
      case cmPolicies::REQUIRED_ALWAYS:
        // We should never make this policy required, but we handle it
        // here just in case.
        this->CheckCMP0011 = true;
        CM_FALLTHROUGH;
      case cmPolicies::NEW:
        // NEW behavior is to push a (strong) scope.
        this->Makefile->PushPolicy();
        break;
    }
  }
}

cmMakefile::IncludeScope::~IncludeScope()
{
  if (!this->NoPolicyScope) {
    // If we need to enforce policy CMP0011 then the top entry is the
    // one we pushed above.  If the entry is empty, then the included
    // script did not set any policies that might affect the includer so
    // we do not need to enforce the policy.
    if (this->CheckCMP0011 &&
        !this->Makefile->StateSnapshot.HasDefinedPolicyCMP0011()) {
      this->CheckCMP0011 = false;
    }

    // Pop the scope we pushed for the script.
    this->Makefile->PopPolicy();

    // We enforce the policy after the script's policy stack entry has
    // been removed.
    if (this->CheckCMP0011) {
      this->EnforceCMP0011();
    }
  }
  this->Makefile->PopSnapshot(this->ReportError);

  this->Makefile->PopFunctionBlockerBarrier(this->ReportError);

  this->Makefile->Backtrace = this->Makefile->Backtrace.Pop();
}

void cmMakefile::IncludeScope::EnforceCMP0011()
{
  // We check the setting of this policy again because the included
  // script might actually set this policy for its includer.
  switch (this->Makefile->GetPolicyStatus(cmPolicies::CMP0011)) {
    case cmPolicies::WARN:
      // Warn because the user did not set this policy.
      {
        std::ostringstream w;
        w << cmPolicies::GetPolicyWarning(cmPolicies::CMP0011) << "\n"
          << "The included script\n  "
          << this->Makefile->GetExecutionFilePath() << "\n"
          << "affects policy settings.  "
          << "CMake is implying the NO_POLICY_SCOPE option for compatibility, "
          << "so the effects are applied to the including context.";
        this->Makefile->IssueMessage(cmake::AUTHOR_WARNING, w.str());
      }
      break;
    case cmPolicies::REQUIRED_IF_USED:
    case cmPolicies::REQUIRED_ALWAYS: {
      std::ostringstream e;
      /* clang-format off */
      e << cmPolicies::GetRequiredPolicyError(cmPolicies::CMP0011) << "\n"
        << "The included script\n  "
        << this->Makefile->GetExecutionFilePath() << "\n"
        << "affects policy settings, so it requires this policy to be set.";
      /* clang-format on */
      this->Makefile->IssueMessage(cmake::FATAL_ERROR, e.str());
    } break;
    case cmPolicies::OLD:
    case cmPolicies::NEW:
      // The script set this policy.  We assume the purpose of the
      // script is to initialize policies for its includer, and since
      // the policy is now set for later scripts, we do not warn.
      break;
  }
}

bool cmMakefile::ReadDependentFile(const char* filename, bool noPolicyScope)
{
  this->AddDefinition("CMAKE_PARENT_LIST_FILE",
                      this->GetDefinition("CMAKE_CURRENT_LIST_FILE"));
  std::string filenametoread = cmSystemTools::CollapseFullPath(
    filename, this->GetCurrentSourceDirectory());

  IncludeScope incScope(this, filenametoread, noPolicyScope);

  cmListFile listFile;
  if (!listFile.ParseFile(filenametoread.c_str(), this->GetMessenger(),
                          this->Backtrace)) {
    return false;
  }

  this->ReadListFile(listFile, filenametoread);
  if (cmSystemTools::GetFatalErrorOccured()) {
    incScope.Quiet();
  }
  return true;
}

class cmMakefile::ListFileScope
{
public:
  ListFileScope(cmMakefile* mf, std::string const& filenametoread)
    : Makefile(mf)
    , ReportError(true)
  {
    this->Makefile->Backtrace = this->Makefile->Backtrace.Push(filenametoread);

    this->Makefile->StateSnapshot =
      this->Makefile->GetState()->CreateInlineListFileSnapshot(
        this->Makefile->StateSnapshot, filenametoread);
    assert(this->Makefile->StateSnapshot.IsValid());

    this->Makefile->PushFunctionBlockerBarrier();
  }

  ~ListFileScope()
  {
    this->Makefile->PopSnapshot(this->ReportError);
    this->Makefile->PopFunctionBlockerBarrier(this->ReportError);
    this->Makefile->Backtrace = this->Makefile->Backtrace.Pop();
  }

  void Quiet() { this->ReportError = false; }

private:
  cmMakefile* Makefile;
  bool ReportError;
};

bool cmMakefile::ReadListFile(const char* filename)
{
  std::string filenametoread = cmSystemTools::CollapseFullPath(
    filename, this->GetCurrentSourceDirectory());

  ListFileScope scope(this, filenametoread);

  cmListFile listFile;
  if (!listFile.ParseFile(filenametoread.c_str(), this->GetMessenger(),
                          this->Backtrace)) {
    return false;
  }

  this->ReadListFile(listFile, filenametoread);
  if (cmSystemTools::GetFatalErrorOccured()) {
    scope.Quiet();
  }
  return true;
}

void cmMakefile::ReadListFile(cmListFile const& listFile,
                              std::string const& filenametoread)
{
  // add this list file to the list of dependencies
  this->ListFiles.push_back(filenametoread);

  std::string currentParentFile =
    this->GetSafeDefinition("CMAKE_PARENT_LIST_FILE");
  std::string currentFile = this->GetSafeDefinition("CMAKE_CURRENT_LIST_FILE");

  this->AddDefinition("CMAKE_CURRENT_LIST_FILE", filenametoread.c_str());
  this->AddDefinition("CMAKE_CURRENT_LIST_DIR",
                      cmSystemTools::GetFilenamePath(filenametoread).c_str());

  this->MarkVariableAsUsed("CMAKE_PARENT_LIST_FILE");
  this->MarkVariableAsUsed("CMAKE_CURRENT_LIST_FILE");
  this->MarkVariableAsUsed("CMAKE_CURRENT_LIST_DIR");

  // Run the parsed commands.
  const size_t numberFunctions = listFile.Functions.size();
  for (size_t i = 0; i < numberFunctions; ++i) {
    cmExecutionStatus status;
    this->ExecuteCommand(listFile.Functions[i], status);
    if (cmSystemTools::GetFatalErrorOccured()) {
      break;
    }
    if (status.GetReturnInvoked()) {
      // Exit early due to return command.
      break;
    }
  }
  this->CheckForUnusedVariables();

  this->AddDefinition("CMAKE_PARENT_LIST_FILE", currentParentFile.c_str());
  this->AddDefinition("CMAKE_CURRENT_LIST_FILE", currentFile.c_str());
  this->AddDefinition("CMAKE_CURRENT_LIST_DIR",
                      cmSystemTools::GetFilenamePath(currentFile).c_str());
  this->MarkVariableAsUsed("CMAKE_PARENT_LIST_FILE");
  this->MarkVariableAsUsed("CMAKE_CURRENT_LIST_FILE");
  this->MarkVariableAsUsed("CMAKE_CURRENT_LIST_DIR");
}

void cmMakefile::EnforceDirectoryLevelRules() const
{
  // Diagnose a violation of CMP0000 if necessary.
  if (this->CheckCMP0000) {
    std::ostringstream msg;
    msg << "No cmake_minimum_required command is present.  "
        << "A line of code such as\n"
        << "  cmake_minimum_required(VERSION " << cmVersion::GetMajorVersion()
        << "." << cmVersion::GetMinorVersion() << ")\n"
        << "should be added at the top of the file.  "
        << "The version specified may be lower if you wish to "
        << "support older CMake versions for this project.  "
        << "For more information run "
        << "\"cmake --help-policy CMP0000\".";
    switch (this->GetPolicyStatus(cmPolicies::CMP0000)) {
      case cmPolicies::WARN:
        // Warn because the user did not provide a minimum required
        // version.
        this->GetCMakeInstance()->IssueMessage(cmake::AUTHOR_WARNING,
                                               msg.str(), this->Backtrace);
      case cmPolicies::OLD:
        // OLD behavior is to use policy version 2.4 set in
        // cmListFileCache.
        break;
      case cmPolicies::REQUIRED_IF_USED:
      case cmPolicies::REQUIRED_ALWAYS:
      case cmPolicies::NEW:
        // NEW behavior is to issue an error.
        this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, msg.str(),
                                               this->Backtrace);
        cmSystemTools::SetFatalErrorOccured();
        return;
    }
  }
}

void cmMakefile::AddEvaluationFile(
  const std::string& inputFile,
  std::unique_ptr<cmCompiledGeneratorExpression> outputName,
  std::unique_ptr<cmCompiledGeneratorExpression> condition,
  bool inputIsContent)
{
  this->EvaluationFiles.push_back(new cmGeneratorExpressionEvaluationFile(
    inputFile, std::move(outputName), std::move(condition), inputIsContent,
    this->GetPolicyStatus(cmPolicies::CMP0070)));
}

std::vector<cmGeneratorExpressionEvaluationFile*>
cmMakefile::GetEvaluationFiles() const
{
  return this->EvaluationFiles;
}

std::vector<cmExportBuildFileGenerator*>
cmMakefile::GetExportBuildFileGenerators() const
{
  return this->ExportBuildFileGenerators;
}

void cmMakefile::RemoveExportBuildFileGeneratorCMP0024(
  cmExportBuildFileGenerator* gen)
{
  std::vector<cmExportBuildFileGenerator*>::iterator it =
    std::find(this->ExportBuildFileGenerators.begin(),
              this->ExportBuildFileGenerators.end(), gen);
  if (it != this->ExportBuildFileGenerators.end()) {
    this->ExportBuildFileGenerators.erase(it);
  }
}

void cmMakefile::AddExportBuildFileGenerator(cmExportBuildFileGenerator* gen)
{
  this->ExportBuildFileGenerators.push_back(gen);
}

namespace {
struct file_not_persistent
{
  bool operator()(const std::string& path) const
  {
    return !(path.find("CMakeTmp") == std::string::npos &&
             cmSystemTools::FileExists(path.c_str()));
  }
};
}

void cmMakefile::FinalPass()
{
  // do all the variable expansions here
  this->ExpandVariablesCMP0019();

  // give all the commands a chance to do something
  // after the file has been parsed before generation
  for (cmCommand* fpCommand : this->FinalPassCommands) {
    fpCommand->FinalPass();
  }

  // go through all configured files and see which ones still exist.
  // we don't want cmake to re-run if a configured file is created and deleted
  // during processing as that would make it a transient file that can't
  // influence the build process
  cmEraseIf(this->OutputFiles, file_not_persistent());

  // if a configured file is used as input for another configured file,
  // and then deleted it will show up in the input list files so we
  // need to scan those too
  cmEraseIf(this->ListFiles, file_not_persistent());
}

// Generate the output file
void cmMakefile::ConfigureFinalPass()
{
  this->FinalPass();
  const char* oldValue = this->GetDefinition("CMAKE_BACKWARDS_COMPATIBILITY");
  if (oldValue &&
      cmSystemTools::VersionCompare(cmSystemTools::OP_LESS, oldValue, "2.4")) {
    this->GetCMakeInstance()->IssueMessage(
      cmake::FATAL_ERROR,
      "You have set CMAKE_BACKWARDS_COMPATIBILITY to a CMake version less "
      "than 2.4. This version of CMake only supports backwards compatibility "
      "with CMake 2.4 or later. For compatibility with older versions please "
      "use any CMake 2.8.x release or lower.",
      this->Backtrace);
  }
}

void cmMakefile::AddCustomCommandToTarget(
  const std::string& target, const std::vector<std::string>& byproducts,
  const std::vector<std::string>& depends,
  const cmCustomCommandLines& commandLines, cmTarget::CustomCommandType type,
  const char* comment, const char* workingDir, bool escapeOldStyle,
  bool uses_terminal, const std::string& depfile, bool command_expand_lists,
  ObjectLibraryCommands objLibraryCommands)
{
  // Find the target to which to add the custom command.
  cmTargets::iterator ti = this->Targets.find(target);

  if (ti == this->Targets.end()) {
    cmake::MessageType messageType = cmake::AUTHOR_WARNING;
    bool issueMessage = false;
    std::ostringstream e;
    switch (this->GetPolicyStatus(cmPolicies::CMP0040)) {
      case cmPolicies::WARN:
        e << cmPolicies::GetPolicyWarning(cmPolicies::CMP0040) << "\n";
        issueMessage = true;
      case cmPolicies::OLD:
        break;
      case cmPolicies::NEW:
      case cmPolicies::REQUIRED_IF_USED:
      case cmPolicies::REQUIRED_ALWAYS:
        issueMessage = true;
        messageType = cmake::FATAL_ERROR;
    }

    if (issueMessage) {
      if (cmTarget const* t = this->FindTargetToUse(target)) {
        if (t->IsImported()) {
          e << "TARGET '" << target
            << "' is IMPORTED and does not build here.";
        } else {
          e << "TARGET '" << target << "' was not created in this directory.";
        }
      } else {
        e << "No TARGET '" << target
          << "' has been created in this directory.";
      }
      IssueMessage(messageType, e.str());
    }

    return;
  }

  if (objLibraryCommands == RejectObjectLibraryCommands &&
      ti->second.GetType() == cmStateEnums::OBJECT_LIBRARY) {
    std::ostringstream e;
    e << "Target \"" << target
      << "\" is an OBJECT library "
         "that may not have PRE_BUILD, PRE_LINK, or POST_BUILD commands.";
    this->IssueMessage(cmake::FATAL_ERROR, e.str());
    return;
  }
  if (ti->second.GetType() == cmStateEnums::INTERFACE_LIBRARY) {
    std::ostringstream e;
    e << "Target \"" << target
      << "\" is an INTERFACE library "
         "that may not have PRE_BUILD, PRE_LINK, or POST_BUILD commands.";
    this->IssueMessage(cmake::FATAL_ERROR, e.str());
    return;
  }

  // Always create the byproduct sources and mark them generated.
  for (std::string const& o : byproducts) {
    if (cmSourceFile* out = this->GetOrCreateSource(o, true)) {
      out->SetProperty("GENERATED", "1");
    }
  }

  // Add the command to the appropriate build step for the target.
  std::vector<std::string> no_output;
  cmCustomCommand cc(this, no_output, byproducts, depends, commandLines,
                     comment, workingDir);
  cc.SetEscapeOldStyle(escapeOldStyle);
  cc.SetEscapeAllowMakeVars(true);
  cc.SetUsesTerminal(uses_terminal);
  cc.SetCommandExpandLists(command_expand_lists);
  cc.SetDepfile(depfile);
  switch (type) {
    case cmTarget::PRE_BUILD:
      ti->second.AddPreBuildCommand(cc);
      break;
    case cmTarget::PRE_LINK:
      ti->second.AddPreLinkCommand(cc);
      break;
    case cmTarget::POST_BUILD:
      ti->second.AddPostBuildCommand(cc);
      break;
  }
}

cmSourceFile* cmMakefile::AddCustomCommandToOutput(
  const std::vector<std::string>& outputs,
  const std::vector<std::string>& byproducts,
  const std::vector<std::string>& depends, const std::string& main_dependency,
  const cmCustomCommandLines& commandLines, const char* comment,
  const char* workingDir, bool replace, bool escapeOldStyle,
  bool uses_terminal, bool command_expand_lists, const std::string& depfile)
{
  // Make sure there is at least one output.
  if (outputs.empty()) {
    cmSystemTools::Error("Attempt to add a custom rule with no output!");
    return nullptr;
  }

  // Validate custom commands.  TODO: More strict?
  for (cmCustomCommandLine const& cl : commandLines) {
    if (!cl.empty() && !cl[0].empty() && cl[0][0] == '"') {
      std::ostringstream e;
      e << "COMMAND may not contain literal quotes:\n  " << cl[0] << "\n";
      this->IssueMessage(cmake::FATAL_ERROR, e.str());
      return nullptr;
    }
  }

  // Choose a source file on which to store the custom command.
  cmSourceFile* file = nullptr;
  if (!commandLines.empty() && !main_dependency.empty()) {
    // The main dependency was specified.  Use it unless a different
    // custom command already used it.
    file = this->GetSource(main_dependency);
    if (file && file->GetCustomCommand() && !replace) {
      // The main dependency already has a custom command.
      if (commandLines == file->GetCustomCommand()->GetCommandLines()) {
        // The existing custom command is identical.  Silently ignore
        // the duplicate.
        return file;
      }
      // The existing custom command is different.  We need to
      // generate a rule file for this new command.
      file = nullptr;
    } else if (!file) {
      file = this->CreateSource(main_dependency);
    }
  }

  // Generate a rule file if the main dependency is not available.
  if (!file) {
    cmGlobalGenerator* gg = this->GetGlobalGenerator();

    // Construct a rule file associated with the first output produced.
    std::string outName = gg->GenerateRuleFile(outputs[0]);

    // Check if the rule file already exists.
    file = this->GetSource(outName);
    if (file && file->GetCustomCommand() && !replace) {
      // The rule file already exists.
      if (commandLines != file->GetCustomCommand()->GetCommandLines()) {
        cmSystemTools::Error("Attempt to add a custom rule to output \"",
                             outName.c_str(),
                             "\" which already has a custom rule.");
      }
      return file;
    }

    // Create a cmSourceFile for the rule file.
    if (!file) {
      file = this->CreateSource(outName, true);
    }
    file->SetProperty("__CMAKE_RULE", "1");
  }

  // Always create the output sources and mark them generated.
  for (std::string const& o : outputs) {
    if (cmSourceFile* out = this->GetOrCreateSource(o, true)) {
      out->SetProperty("GENERATED", "1");
    }
  }
  for (std::string const& o : byproducts) {
    if (cmSourceFile* out = this->GetOrCreateSource(o, true)) {
      out->SetProperty("GENERATED", "1");
    }
  }

  // Attach the custom command to the file.
  if (file) {
    // Construct a complete list of dependencies.
    std::vector<std::string> depends2(depends);
    if (!main_dependency.empty()) {
      depends2.push_back(main_dependency);
    }

    cmCustomCommand* cc = new cmCustomCommand(
      this, outputs, byproducts, depends2, commandLines, comment, workingDir);
    cc->SetEscapeOldStyle(escapeOldStyle);
    cc->SetEscapeAllowMakeVars(true);
    cc->SetUsesTerminal(uses_terminal);
    cc->SetCommandExpandLists(command_expand_lists);
    cc->SetDepfile(depfile);
    file->SetCustomCommand(cc);
    this->UpdateOutputToSourceMap(outputs, file);
  }
  return file;
}

void cmMakefile::UpdateOutputToSourceMap(
  std::vector<std::string> const& outputs, cmSourceFile* source)
{
  for (std::string const& o : outputs) {
    this->UpdateOutputToSourceMap(o, source);
  }
}

void cmMakefile::UpdateOutputToSourceMap(std::string const& output,
                                         cmSourceFile* source)
{
  OutputToSourceMap::iterator i = this->OutputToSource.find(output);
  if (i != this->OutputToSource.end()) {
    // Multiple custom commands produce the same output but may
    // be attached to a different source file (MAIN_DEPENDENCY).
    // LinearGetSourceFileWithOutput would return the first one,
    // so keep the mapping for the first one.
    //
    // TODO: Warn the user about this case.  However, the VS 8 generator
    // triggers it for separate generate.stamp rules in ZERO_CHECK and
    // individual targets.
    return;
  }
  this->OutputToSource[output] = source;
}

cmSourceFile* cmMakefile::AddCustomCommandToOutput(
  const std::string& output, const std::vector<std::string>& depends,
  const std::string& main_dependency, const cmCustomCommandLines& commandLines,
  const char* comment, const char* workingDir, bool replace,
  bool escapeOldStyle, bool uses_terminal, bool command_expand_lists,
  const std::string& depfile)
{
  std::vector<std::string> outputs;
  outputs.push_back(output);
  std::vector<std::string> no_byproducts;
  return this->AddCustomCommandToOutput(
    outputs, no_byproducts, depends, main_dependency, commandLines, comment,
    workingDir, replace, escapeOldStyle, uses_terminal, command_expand_lists,
    depfile);
}

void cmMakefile::AddCustomCommandOldStyle(
  const std::string& target, const std::vector<std::string>& outputs,
  const std::vector<std::string>& depends, const std::string& source,
  const cmCustomCommandLines& commandLines, const char* comment)
{
  // Translate the old-style signature to one of the new-style
  // signatures.
  if (source == target) {
    // In the old-style signature if the source and target were the
    // same then it added a post-build rule to the target.  Preserve
    // this behavior.
    std::vector<std::string> no_byproducts;
    this->AddCustomCommandToTarget(target, no_byproducts, depends,
                                   commandLines, cmTarget::POST_BUILD, comment,
                                   nullptr);
    return;
  }

  // Each output must get its own copy of this rule.
  cmsys::RegularExpression sourceFiles("\\.(C|M|c|c\\+\\+|cc|cpp|cxx|cu|m|mm|"
                                       "rc|def|r|odl|idl|hpj|bat|h|h\\+\\+|"
                                       "hm|hpp|hxx|in|txx|inl)$");
  for (std::string const& oi : outputs) {
    // Get the name of this output.
    const char* output = oi.c_str();
    cmSourceFile* sf;

    // Choose whether to use a main dependency.
    if (sourceFiles.find(source)) {
      // The source looks like a real file.  Use it as the main dependency.
      sf = this->AddCustomCommandToOutput(output, depends, source,
                                          commandLines, comment, nullptr);
    } else {
      // The source may not be a real file.  Do not use a main dependency.
      std::string no_main_dependency;
      std::vector<std::string> depends2 = depends;
      depends2.push_back(source);
      sf = this->AddCustomCommandToOutput(output, depends2, no_main_dependency,
                                          commandLines, comment, nullptr);
    }

    // If the rule was added to the source (and not a .rule file),
    // then add the source to the target to make sure the rule is
    // included.
    if (sf && !sf->GetPropertyAsBool("__CMAKE_RULE")) {
      cmTargets::iterator ti = this->Targets.find(target);
      if (ti != this->Targets.end()) {
        ti->second.AddSource(sf->GetFullPath());
      } else {
        cmSystemTools::Error("Attempt to add a custom rule to a target "
                             "that does not exist yet for target ",
                             target.c_str());
        return;
      }
    }
  }
}

cmTarget* cmMakefile::AddUtilityCommand(
  const std::string& utilityName, TargetOrigin origin, bool excludeFromAll,
  const std::vector<std::string>& depends, const char* workingDirectory,
  const char* command, const char* arg1, const char* arg2, const char* arg3,
  const char* arg4)
{
  // Construct the command line for the custom command.
  cmCustomCommandLine commandLine;
  commandLine.push_back(command);
  if (arg1) {
    commandLine.push_back(arg1);
  }
  if (arg2) {
    commandLine.push_back(arg2);
  }
  if (arg3) {
    commandLine.push_back(arg3);
  }
  if (arg4) {
    commandLine.push_back(arg4);
  }
  cmCustomCommandLines commandLines;
  commandLines.push_back(commandLine);

  // Call the real signature of this method.
  return this->AddUtilityCommand(utilityName, origin, excludeFromAll,
                                 workingDirectory, depends, commandLines);
}

cmTarget* cmMakefile::AddUtilityCommand(
  const std::string& utilityName, TargetOrigin origin, bool excludeFromAll,
  const char* workingDirectory, const std::vector<std::string>& depends,
  const cmCustomCommandLines& commandLines, bool escapeOldStyle,
  const char* comment, bool uses_terminal, bool command_expand_lists)
{
  std::vector<std::string> no_byproducts;
  return this->AddUtilityCommand(utilityName, origin, excludeFromAll,
                                 workingDirectory, no_byproducts, depends,
                                 commandLines, escapeOldStyle, comment,
                                 uses_terminal, command_expand_lists);
}

cmTarget* cmMakefile::AddUtilityCommand(
  const std::string& utilityName, TargetOrigin origin, bool excludeFromAll,
  const char* workingDirectory, const std::vector<std::string>& byproducts,
  const std::vector<std::string>& depends,
  const cmCustomCommandLines& commandLines, bool escapeOldStyle,
  const char* comment, bool uses_terminal, bool command_expand_lists)
{
  // Create a target instance for this utility.
  cmTarget* target = this->AddNewTarget(cmStateEnums::UTILITY, utilityName);
  target->SetIsGeneratorProvided(origin == TargetOrigin::Generator);
  if (excludeFromAll) {
    target->SetProperty("EXCLUDE_FROM_ALL", "TRUE");
  }
  if (!comment) {
    // Use an empty comment to avoid generation of default comment.
    comment = "";
  }

  // Store the custom command in the target.
  if (!commandLines.empty() || !depends.empty()) {
    std::string force = this->GetCurrentBinaryDirectory();
    force += cmake::GetCMakeFilesDirectory();
    force += "/";
    force += utilityName;
    std::vector<std::string> forced;
    forced.push_back(force);
    std::string no_main_dependency;
    bool no_replace = false;
    this->AddCustomCommandToOutput(
      forced, byproducts, depends, no_main_dependency, commandLines, comment,
      workingDirectory, no_replace, escapeOldStyle, uses_terminal,
      command_expand_lists);
    cmSourceFile* sf = target->AddSourceCMP0049(force);

    // The output is not actually created so mark it symbolic.
    if (sf) {
      sf->SetProperty("SYMBOLIC", "1");
    } else {
      cmSystemTools::Error("Could not get source file entry for ",
                           force.c_str());
    }

    // Always create the byproduct sources and mark them generated.
    for (std::string const& byproduct : byproducts) {
      if (cmSourceFile* out = this->GetOrCreateSource(byproduct, true)) {
        out->SetProperty("GENERATED", "1");
      }
    }
  }
  return target;
}

void cmMakefile::AddDefineFlag(const char* flag)
{
  if (!flag) {
    return;
  }

  // Update the string used for the old DEFINITIONS property.
  this->AddDefineFlag(flag, this->DefineFlagsOrig);

  // If this is really a definition, update COMPILE_DEFINITIONS.
  if (this->ParseDefineFlag(flag, false)) {
    return;
  }

  // Add this flag that does not look like a definition.
  this->AddDefineFlag(flag, this->DefineFlags);
}

void cmMakefile::AddDefineFlag(const char* flag, std::string& dflags)
{
  // remove any \n\r
  std::string::size_type initSize = dflags.size();
  dflags += std::string(" ") + flag;
  std::string::iterator flagStart = dflags.begin() + initSize + 1;
  std::replace(flagStart, dflags.end(), '\n', ' ');
  std::replace(flagStart, dflags.end(), '\r', ' ');
}

void cmMakefile::RemoveDefineFlag(const char* flag)
{
  // Check the length of the flag to remove.
  std::string::size_type len = strlen(flag);
  if (len < 1) {
    return;
  }

  // Update the string used for the old DEFINITIONS property.
  this->RemoveDefineFlag(flag, len, this->DefineFlagsOrig);

  // If this is really a definition, update COMPILE_DEFINITIONS.
  if (this->ParseDefineFlag(flag, true)) {
    return;
  }

  // Remove this flag that does not look like a definition.
  this->RemoveDefineFlag(flag, len, this->DefineFlags);
}

void cmMakefile::RemoveDefineFlag(const char* flag, std::string::size_type len,
                                  std::string& dflags)
{
  // Remove all instances of the flag that are surrounded by
  // whitespace or the beginning/end of the string.
  for (std::string::size_type lpos = dflags.find(flag, 0);
       lpos != std::string::npos; lpos = dflags.find(flag, lpos)) {
    std::string::size_type rpos = lpos + len;
    if ((lpos <= 0 || isspace(dflags[lpos - 1])) &&
        (rpos >= dflags.size() || isspace(dflags[rpos]))) {
      dflags.erase(lpos, len);
    } else {
      ++lpos;
    }
  }
}

void cmMakefile::AddCompileOption(const char* option)
{
  this->AppendProperty("COMPILE_OPTIONS", option);
}

bool cmMakefile::ParseDefineFlag(std::string const& def, bool remove)
{
  // Create a regular expression to match valid definitions.
  static cmsys::RegularExpression valid("^[-/]D[A-Za-z_][A-Za-z0-9_]*(=.*)?$");

  // Make sure the definition matches.
  if (!valid.find(def.c_str())) {
    return false;
  }

  // Definitions with non-trivial values require a policy check.
  static cmsys::RegularExpression trivial(
    "^[-/]D[A-Za-z_][A-Za-z0-9_]*(=[A-Za-z0-9_.]+)?$");
  if (!trivial.find(def.c_str())) {
    // This definition has a non-trivial value.
    switch (this->GetPolicyStatus(cmPolicies::CMP0005)) {
      case cmPolicies::WARN:
        this->IssueMessage(cmake::AUTHOR_WARNING,
                           cmPolicies::GetPolicyWarning(cmPolicies::CMP0005));
        CM_FALLTHROUGH;
      case cmPolicies::OLD:
        // OLD behavior is to not escape the value.  We should not
        // convert the definition to use the property.
        return false;
      case cmPolicies::REQUIRED_IF_USED:
      case cmPolicies::REQUIRED_ALWAYS:
        this->IssueMessage(
          cmake::FATAL_ERROR,
          cmPolicies::GetRequiredPolicyError(cmPolicies::CMP0005));
        return false;
      case cmPolicies::NEW:
        // NEW behavior is to escape the value.  Proceed to convert it
        // to an entry in the property.
        break;
    }
  }

  // Get the definition part after the flag.
  const char* define = def.c_str() + 2;

  if (remove) {
    if (const char* cdefs = this->GetProperty("COMPILE_DEFINITIONS")) {
      // Expand the list.
      std::vector<std::string> defs;
      cmSystemTools::ExpandListArgument(cdefs, defs);

      // Recompose the list without the definition.
      std::vector<std::string>::const_iterator defEnd =
        std::remove(defs.begin(), defs.end(), define);
      std::vector<std::string>::const_iterator defBegin = defs.begin();
      std::string ndefs = cmJoin(cmMakeRange(defBegin, defEnd), ";");

      // Store the new list.
      this->SetProperty("COMPILE_DEFINITIONS", ndefs.c_str());
    }
  } else {
    // Append the definition to the directory property.
    this->AppendProperty("COMPILE_DEFINITIONS", define);
  }

  return true;
}

void cmMakefile::InitializeFromParent(cmMakefile* parent)
{
  this->SystemIncludeDirectories = parent->SystemIncludeDirectories;

  // define flags
  this->DefineFlags = parent->DefineFlags;
  this->DefineFlagsOrig = parent->DefineFlagsOrig;

  // Include transform property.  There is no per-config version.
  {
    const char* prop = "IMPLICIT_DEPENDS_INCLUDE_TRANSFORM";
    this->SetProperty(prop, parent->GetProperty(prop));
  }

  // compile definitions property and per-config versions
  cmPolicies::PolicyStatus polSt = this->GetPolicyStatus(cmPolicies::CMP0043);
  if (polSt == cmPolicies::WARN || polSt == cmPolicies::OLD) {
    this->SetProperty("COMPILE_DEFINITIONS",
                      parent->GetProperty("COMPILE_DEFINITIONS"));
    std::vector<std::string> configs;
    this->GetConfigurations(configs);
    for (std::string const& config : configs) {
      std::string defPropName = "COMPILE_DEFINITIONS_";
      defPropName += cmSystemTools::UpperCase(config);
      const char* prop = parent->GetProperty(defPropName);
      this->SetProperty(defPropName, prop);
    }
  }

  // labels
  this->SetProperty("LABELS", parent->GetProperty("LABELS"));

  // link libraries
  this->SetProperty("LINK_LIBRARIES", parent->GetProperty("LINK_LIBRARIES"));

  // link directories
  this->SetProperty("LINK_DIRECTORIES",
                    parent->GetProperty("LINK_DIRECTORIES"));

  // the initial project name
  this->StateSnapshot.SetProjectName(parent->StateSnapshot.GetProjectName());

  // Copy include regular expressions.
  this->ComplainFileRegularExpression = parent->ComplainFileRegularExpression;

  // Imported targets.
  this->ImportedTargets = parent->ImportedTargets;
}

void cmMakefile::PushFunctionScope(std::string const& fileName,
                                   const cmPolicies::PolicyMap& pm)
{
  this->StateSnapshot = this->GetState()->CreateFunctionCallSnapshot(
    this->StateSnapshot, fileName);
  assert(this->StateSnapshot.IsValid());

  this->PushLoopBlockBarrier();

#if defined(CMAKE_BUILD_WITH_CMAKE)
  this->GetGlobalGenerator()->GetFileLockPool().PushFunctionScope();
#endif

  this->PushFunctionBlockerBarrier();

  this->PushPolicy(true, pm);
}

void cmMakefile::PopFunctionScope(bool reportError)
{
  this->PopPolicy();

  this->PopSnapshot(reportError);

  this->PopFunctionBlockerBarrier(reportError);

#if defined(CMAKE_BUILD_WITH_CMAKE)
  this->GetGlobalGenerator()->GetFileLockPool().PopFunctionScope();
#endif

  this->PopLoopBlockBarrier();

  this->CheckForUnusedVariables();
}

void cmMakefile::PushMacroScope(std::string const& fileName,
                                const cmPolicies::PolicyMap& pm)
{
  this->StateSnapshot =
    this->GetState()->CreateMacroCallSnapshot(this->StateSnapshot, fileName);
  assert(this->StateSnapshot.IsValid());

  this->PushFunctionBlockerBarrier();

  this->PushPolicy(true, pm);
}

void cmMakefile::PopMacroScope(bool reportError)
{
  this->PopPolicy();
  this->PopSnapshot(reportError);

  this->PopFunctionBlockerBarrier(reportError);
}

bool cmMakefile::IsRootMakefile() const
{
  return !this->StateSnapshot.GetBuildsystemDirectoryParent().IsValid();
}

class cmMakefile::BuildsystemFileScope
{
public:
  BuildsystemFileScope(cmMakefile* mf)
    : Makefile(mf)
    , ReportError(true)
  {
    std::string currentStart =
      this->Makefile->StateSnapshot.GetDirectory().GetCurrentSource();
    currentStart += "/CMakeLists.txt";
    this->Makefile->StateSnapshot.SetListFile(currentStart);
    this->Makefile->StateSnapshot =
      this->Makefile->StateSnapshot.GetState()->CreatePolicyScopeSnapshot(
        this->Makefile->StateSnapshot);
    this->Makefile->PushFunctionBlockerBarrier();

    this->GG = mf->GetGlobalGenerator();
    this->CurrentMakefile = this->GG->GetCurrentMakefile();
    this->Snapshot = this->GG->GetCMakeInstance()->GetCurrentSnapshot();
    this->GG->GetCMakeInstance()->SetCurrentSnapshot(this->Snapshot);
    this->GG->SetCurrentMakefile(mf);
#if defined(CMAKE_BUILD_WITH_CMAKE)
    this->GG->GetFileLockPool().PushFileScope();
#endif
  }

  ~BuildsystemFileScope()
  {
    this->Makefile->PopFunctionBlockerBarrier(this->ReportError);
    this->Makefile->PopSnapshot(this->ReportError);
#if defined(CMAKE_BUILD_WITH_CMAKE)
    this->GG->GetFileLockPool().PopFileScope();
#endif
    this->GG->SetCurrentMakefile(this->CurrentMakefile);
    this->GG->GetCMakeInstance()->SetCurrentSnapshot(this->Snapshot);
  }

  void Quiet() { this->ReportError = false; }

private:
  cmMakefile* Makefile;
  cmGlobalGenerator* GG;
  cmMakefile* CurrentMakefile;
  cmStateSnapshot Snapshot;
  bool ReportError;
};

void cmMakefile::Configure()
{
  std::string currentStart =
    this->StateSnapshot.GetDirectory().GetCurrentSource();
  currentStart += "/CMakeLists.txt";

  // Add the bottom of all backtraces within this directory.
  // We will never pop this scope because it should be available
  // for messages during the generate step too.
  this->Backtrace = this->Backtrace.Push(currentStart);

  BuildsystemFileScope scope(this);

  // make sure the CMakeFiles dir is there
  std::string filesDir = this->StateSnapshot.GetDirectory().GetCurrentBinary();
  filesDir += cmake::GetCMakeFilesDirectory();
  cmSystemTools::MakeDirectory(filesDir.c_str());

  assert(cmSystemTools::FileExists(currentStart.c_str(), true));
  this->AddDefinition("CMAKE_PARENT_LIST_FILE", currentStart.c_str());

  cmListFile listFile;
  if (!listFile.ParseFile(currentStart.c_str(), this->GetMessenger(),
                          this->Backtrace)) {
    return;
  }
  if (this->IsRootMakefile()) {
    bool hasVersion = false;
    // search for the right policy command
    for (cmListFileFunction const& func : listFile.Functions) {
      if (cmSystemTools::LowerCase(func.Name) == "cmake_minimum_required") {
        hasVersion = true;
        break;
      }
    }
    // if no policy command is found this is an error if they use any
    // non advanced functions or a lot of functions
    if (!hasVersion) {
      bool isProblem = true;
      if (listFile.Functions.size() < 30) {
        // the list of simple commands DO NOT ADD TO THIS LIST!!!!!
        // these commands must have backwards compatibility forever and
        // and that is a lot longer than your tiny mind can comprehend mortal
        std::set<std::string> allowedCommands;
        allowedCommands.insert("project");
        allowedCommands.insert("set");
        allowedCommands.insert("if");
        allowedCommands.insert("endif");
        allowedCommands.insert("else");
        allowedCommands.insert("elseif");
        allowedCommands.insert("add_executable");
        allowedCommands.insert("add_library");
        allowedCommands.insert("target_link_libraries");
        allowedCommands.insert("option");
        allowedCommands.insert("message");
        isProblem = false;
        for (cmListFileFunction const& func : listFile.Functions) {
          std::string name = cmSystemTools::LowerCase(func.Name);
          if (allowedCommands.find(name) == allowedCommands.end()) {
            isProblem = true;
            break;
          }
        }
      }

      if (isProblem) {
        // Tell the top level cmMakefile to diagnose
        // this violation of CMP0000.
        this->SetCheckCMP0000(true);

        // Implicitly set the version for the user.
        this->SetPolicyVersion("2.4");
      }
    }
    bool hasProject = false;
    // search for a project command
    for (cmListFileFunction const& func : listFile.Functions) {
      if (cmSystemTools::LowerCase(func.Name) == "project") {
        hasProject = true;
        break;
      }
    }
    // if no project command is found, add one
    if (!hasProject) {
      cmListFileFunction project;
      project.Name = "PROJECT";
      cmListFileArgument prj("Project", cmListFileArgument::Unquoted, 0);
      project.Arguments.push_back(prj);
      listFile.Functions.insert(listFile.Functions.begin(), project);
    }
  }

  this->ReadListFile(listFile, currentStart);
  if (cmSystemTools::GetFatalErrorOccured()) {
    scope.Quiet();
  }

  // at the end handle any old style subdirs
  std::vector<cmMakefile*> subdirs = this->UnConfiguredDirectories;

  // for each subdir recurse
  std::vector<cmMakefile*>::iterator sdi = subdirs.begin();
  for (; sdi != subdirs.end(); ++sdi) {
    (*sdi)->StateSnapshot.InitializeFromParent_ForSubdirsCommand();
    this->ConfigureSubDirectory(*sdi);
  }

  this->AddCMakeDependFilesFromUser();
}

void cmMakefile::ConfigureSubDirectory(cmMakefile* mf)
{
  mf->InitializeFromParent(this);
  std::string currentStart = mf->GetCurrentSourceDirectory();
  if (this->GetCMakeInstance()->GetDebugOutput()) {
    std::string msg = "   Entering             ";
    msg += currentStart;
    cmSystemTools::Message(msg.c_str());
  }

  std::string const currentStartFile = currentStart + "/CMakeLists.txt";
  if (!cmSystemTools::FileExists(currentStartFile, true)) {
    // The file is missing.  Check policy CMP0014.
    std::ostringstream e;
    /* clang-format off */
    e << "The source directory\n"
      << "  " << currentStart << "\n"
      << "does not contain a CMakeLists.txt file.";
    /* clang-format on */
    switch (this->GetPolicyStatus(cmPolicies::CMP0014)) {
      case cmPolicies::WARN:
        // Print the warning.
        /* clang-format off */
        e << "\n"
          << "CMake does not support this case but it used "
          << "to work accidentally and is being allowed for "
          << "compatibility."
          << "\n"
          << cmPolicies::GetPolicyWarning(cmPolicies::CMP0014);
        /* clang-format on */
        this->IssueMessage(cmake::AUTHOR_WARNING, e.str());
      case cmPolicies::OLD:
        // OLD behavior does not warn.
        break;
      case cmPolicies::REQUIRED_IF_USED:
      case cmPolicies::REQUIRED_ALWAYS:
        e << "\n" << cmPolicies::GetRequiredPolicyError(cmPolicies::CMP0014);
        CM_FALLTHROUGH;
      case cmPolicies::NEW:
        // NEW behavior prints the error.
        this->IssueMessage(cmake::FATAL_ERROR, e.str());
    }
    return;
  }
  // finally configure the subdir
  mf->Configure();

  if (this->GetCMakeInstance()->GetDebugOutput()) {
    std::string msg = "   Returning to         ";
    msg += this->GetCurrentSourceDirectory();
    cmSystemTools::Message(msg.c_str());
  }
}

void cmMakefile::AddSubDirectory(const std::string& srcPath,
                                 const std::string& binPath,
                                 bool excludeFromAll, bool immediate)
{
  // Make sure the binary directory is unique.
  if (!this->EnforceUniqueDir(srcPath, binPath)) {
    return;
  }

  cmStateSnapshot newSnapshot =
    this->GetState()->CreateBuildsystemDirectorySnapshot(this->StateSnapshot);

  newSnapshot.GetDirectory().SetCurrentSource(srcPath);
  newSnapshot.GetDirectory().SetCurrentBinary(binPath);

  cmSystemTools::MakeDirectory(binPath.c_str());

  cmMakefile* subMf = new cmMakefile(this->GlobalGenerator, newSnapshot);
  this->GetGlobalGenerator()->AddMakefile(subMf);

  if (excludeFromAll) {
    subMf->SetProperty("EXCLUDE_FROM_ALL", "TRUE");
  }

  if (immediate) {
    this->ConfigureSubDirectory(subMf);
  } else {
    this->UnConfiguredDirectories.push_back(subMf);
  }
}

const char* cmMakefile::GetCurrentSourceDirectory() const
{
  return this->StateSnapshot.GetDirectory().GetCurrentSource();
}

const char* cmMakefile::GetCurrentBinaryDirectory() const
{
  return this->StateSnapshot.GetDirectory().GetCurrentBinary();
}

std::vector<cmTarget*> cmMakefile::GetImportedTargets() const
{
  std::vector<cmTarget*> tgts;
  tgts.reserve(this->ImportedTargets.size());
  for (auto const& impTarget : this->ImportedTargets) {
    tgts.push_back(impTarget.second);
  }
  return tgts;
}

void cmMakefile::AddIncludeDirectories(const std::vector<std::string>& incs,
                                       bool before)
{
  if (incs.empty()) {
    return;
  }

  cmListFileBacktrace lfbt = this->GetBacktrace();
  std::string entryString = cmJoin(incs, ";");
  if (before) {
    this->StateSnapshot.GetDirectory().PrependIncludeDirectoriesEntry(
      entryString, lfbt);
  } else {
    this->StateSnapshot.GetDirectory().AppendIncludeDirectoriesEntry(
      entryString, lfbt);
  }

  // Property on each target:
  for (auto& target : this->Targets) {
    cmTarget& t = target.second;
    t.InsertInclude(entryString, lfbt, before);
  }
}

void cmMakefile::AddSystemIncludeDirectories(const std::set<std::string>& incs)
{
  if (incs.empty()) {
    return;
  }

  this->SystemIncludeDirectories.insert(incs.begin(), incs.end());

  for (auto& target : this->Targets) {
    cmTarget& t = target.second;
    t.AddSystemIncludeDirectories(incs);
  }
}

void cmMakefile::AddDefinition(const std::string& name, const char* value)
{
  if (!value) {
    return;
  }

  if (this->VariableInitialized(name)) {
    this->LogUnused("changing definition", name);
  }
  this->StateSnapshot.SetDefinition(name, value);

#ifdef CMAKE_BUILD_WITH_CMAKE
  cmVariableWatch* vv = this->GetVariableWatch();
  if (vv) {
    vv->VariableAccessed(name, cmVariableWatch::VARIABLE_MODIFIED_ACCESS,
                         value, this);
  }
#endif
}

void cmMakefile::AddCacheDefinition(const std::string& name, const char* value,
                                    const char* doc,
                                    cmStateEnums::CacheEntryType type,
                                    bool force)
{
  const char* existingValue = this->GetState()->GetInitializedCacheValue(name);
  // must be outside the following if() to keep it alive long enough
  std::string nvalue;

  if (existingValue && (this->GetState()->GetCacheEntryType(name) ==
                        cmStateEnums::UNINITIALIZED)) {
    // if this is not a force, then use the value from the cache
    // if it is a force, then use the value being passed in
    if (!force) {
      value = existingValue;
    }
    if (type == cmStateEnums::PATH || type == cmStateEnums::FILEPATH) {
      std::vector<std::string>::size_type cc;
      std::vector<std::string> files;
      nvalue = value ? value : "";

      cmSystemTools::ExpandListArgument(nvalue, files);
      nvalue.clear();
      for (cc = 0; cc < files.size(); cc++) {
        if (!cmSystemTools::IsOff(files[cc].c_str())) {
          files[cc] = cmSystemTools::CollapseFullPath(files[cc]);
        }
        if (cc > 0) {
          nvalue += ";";
        }
        nvalue += files[cc];
      }

      this->GetCMakeInstance()->AddCacheEntry(name, nvalue.c_str(), doc, type);
      nvalue = this->GetState()->GetInitializedCacheValue(name);
      value = nvalue.c_str();
    }
  }
  this->GetCMakeInstance()->AddCacheEntry(name, value, doc, type);
  // if there was a definition then remove it
  this->StateSnapshot.RemoveDefinition(name);
}

void cmMakefile::AddDefinition(const std::string& name, bool value)
{
  if (this->VariableInitialized(name)) {
    this->LogUnused("changing definition", name);
  }

  this->StateSnapshot.SetDefinition(name, value ? "ON" : "OFF");

#ifdef CMAKE_BUILD_WITH_CMAKE
  cmVariableWatch* vv = this->GetVariableWatch();
  if (vv) {
    vv->VariableAccessed(name, cmVariableWatch::VARIABLE_MODIFIED_ACCESS,
                         value ? "ON" : "OFF", this);
  }
#endif
}

void cmMakefile::CheckForUnusedVariables() const
{
  if (!this->WarnUnused) {
    return;
  }
  const std::vector<std::string>& unused = this->StateSnapshot.UnusedKeys();
  std::vector<std::string>::const_iterator it = unused.begin();
  for (; it != unused.end(); ++it) {
    this->LogUnused("out of scope", *it);
  }
}

void cmMakefile::MarkVariableAsUsed(const std::string& var)
{
  this->StateSnapshot.GetDefinition(var);
}

bool cmMakefile::VariableInitialized(const std::string& var) const
{
  return this->StateSnapshot.IsInitialized(var);
}

void cmMakefile::LogUnused(const char* reason, const std::string& name) const
{
  if (this->WarnUnused) {
    std::string path;
    if (!this->ExecutionStatusStack.empty()) {
      path = this->GetExecutionContext().FilePath;
    } else {
      path = this->GetCurrentSourceDirectory();
      path += "/CMakeLists.txt";
    }

    if (this->CheckSystemVars ||
        cmSystemTools::IsSubDirectory(path, this->GetHomeDirectory()) ||
        (cmSystemTools::IsSubDirectory(path, this->GetHomeOutputDirectory()) &&
         !cmSystemTools::IsSubDirectory(path,
                                        cmake::GetCMakeFilesDirectory()))) {
      std::ostringstream msg;
      msg << "unused variable (" << reason << ") \'" << name << "\'";
      this->IssueMessage(cmake::AUTHOR_WARNING, msg.str());
    }
  }
}

void cmMakefile::RemoveDefinition(const std::string& name)
{
  if (this->VariableInitialized(name)) {
    this->LogUnused("unsetting", name);
  }
  this->StateSnapshot.RemoveDefinition(name);
#ifdef CMAKE_BUILD_WITH_CMAKE
  cmVariableWatch* vv = this->GetVariableWatch();
  if (vv) {
    vv->VariableAccessed(name, cmVariableWatch::VARIABLE_REMOVED_ACCESS,
                         nullptr, this);
  }
#endif
}

void cmMakefile::RemoveCacheDefinition(const std::string& name)
{
  this->GetState()->RemoveCacheEntry(name);
}

void cmMakefile::SetProjectName(std::string const& p)
{
  this->StateSnapshot.SetProjectName(p);
}

void cmMakefile::AddGlobalLinkInformation(cmTarget& target)
{
  // for these targets do not add anything
  switch (target.GetType()) {
    case cmStateEnums::UTILITY:
    case cmStateEnums::GLOBAL_TARGET:
    case cmStateEnums::INTERFACE_LIBRARY:
      return;
    default:;
  }
  if (const char* linkDirsProp = this->GetProperty("LINK_DIRECTORIES")) {
    std::vector<std::string> linkDirs;
    cmSystemTools::ExpandListArgument(linkDirsProp, linkDirs);

    for (std::string const& linkDir : linkDirs) {
      std::string newdir = linkDir;
      // remove trailing slashes
      if (*linkDir.rbegin() == '/') {
        newdir = linkDir.substr(0, linkDir.size() - 1);
      }
      target.AddLinkDirectory(linkDir);
    }
  }

  if (const char* linkLibsProp = this->GetProperty("LINK_LIBRARIES")) {
    std::vector<std::string> linkLibs;
    cmSystemTools::ExpandListArgument(linkLibsProp, linkLibs);

    for (std::vector<std::string>::iterator j = linkLibs.begin();
         j != linkLibs.end(); ++j) {
      std::string libraryName = *j;
      cmTargetLinkLibraryType libType = GENERAL_LibraryType;
      if (libraryName == "optimized") {
        libType = OPTIMIZED_LibraryType;
        ++j;
        libraryName = *j;
      } else if (libraryName == "debug") {
        libType = DEBUG_LibraryType;
        ++j;
        libraryName = *j;
      }
      // This is equivalent to the target_link_libraries plain signature.
      target.AddLinkLibrary(*this, libraryName, libType);
      target.AppendProperty(
        "INTERFACE_LINK_LIBRARIES",
        target.GetDebugGeneratorExpressions(libraryName, libType).c_str());
    }
  }
}

void cmMakefile::AddAlias(const std::string& lname, std::string const& tgtName)
{
  this->AliasTargets[lname] = tgtName;
  this->GetGlobalGenerator()->AddAlias(lname, tgtName);
}

cmTarget* cmMakefile::AddLibrary(const std::string& lname,
                                 cmStateEnums::TargetType type,
                                 const std::vector<std::string>& srcs,
                                 bool excludeFromAll)
{
  assert(type == cmStateEnums::STATIC_LIBRARY ||
         type == cmStateEnums::SHARED_LIBRARY ||
         type == cmStateEnums::MODULE_LIBRARY ||
         type == cmStateEnums::OBJECT_LIBRARY ||
         type == cmStateEnums::INTERFACE_LIBRARY);

  cmTarget* target = this->AddNewTarget(type, lname);
  // Clear its dependencies. Otherwise, dependencies might persist
  // over changes in CMakeLists.txt, making the information stale and
  // hence useless.
  target->ClearDependencyInformation(*this, lname);
  if (excludeFromAll) {
    target->SetProperty("EXCLUDE_FROM_ALL", "TRUE");
  }
  target->AddSources(srcs);
  this->AddGlobalLinkInformation(*target);
  return target;
}

cmTarget* cmMakefile::AddExecutable(const char* exeName,
                                    const std::vector<std::string>& srcs,
                                    bool excludeFromAll)
{
  cmTarget* target = this->AddNewTarget(cmStateEnums::EXECUTABLE, exeName);
  if (excludeFromAll) {
    target->SetProperty("EXCLUDE_FROM_ALL", "TRUE");
  }
  target->AddSources(srcs);
  this->AddGlobalLinkInformation(*target);
  return target;
}

cmTarget* cmMakefile::AddNewTarget(cmStateEnums::TargetType type,
                                   const std::string& name)
{
  cmTargets::iterator it =
    this->Targets
      .insert(cmTargets::value_type(
        name, cmTarget(name, type, cmTarget::VisibilityNormal, this)))
      .first;
  this->GetGlobalGenerator()->IndexTarget(&it->second);
  this->GetStateSnapshot().GetDirectory().AddNormalTargetName(name);
  return &it->second;
}

cmSourceFile* cmMakefile::LinearGetSourceFileWithOutput(
  const std::string& name) const
{
  std::string out;

  // look through all the source files that have custom commands
  // and see if the custom command has the passed source file as an output
  for (cmSourceFile* src : this->SourceFiles) {
    // does this source file have a custom command?
    if (src->GetCustomCommand()) {
      // Does the output of the custom command match the source file name?
      const std::vector<std::string>& outputs =
        src->GetCustomCommand()->GetOutputs();
      for (std::string const& output : outputs) {
        out = output;
        std::string::size_type pos = out.rfind(name);
        // If the output matches exactly
        if (pos != std::string::npos && pos == out.size() - name.size() &&
            (pos == 0 || out[pos - 1] == '/')) {
          return src;
        }
      }
    }
  }

  // otherwise return NULL
  return nullptr;
}

cmSourceFile* cmMakefile::GetSourceFileWithOutput(
  const std::string& name) const
{
  // If the queried path is not absolute we use the backward compatible
  // linear-time search for an output with a matching suffix.
  if (!cmSystemTools::FileIsFullPath(name.c_str())) {
    return this->LinearGetSourceFileWithOutput(name);
  }
  // Otherwise we use an efficient lookup map.
  OutputToSourceMap::const_iterator o = this->OutputToSource.find(name);
  if (o != this->OutputToSource.end()) {
    return (*o).second;
  }
  return nullptr;
}

#if defined(CMAKE_BUILD_WITH_CMAKE)
cmSourceGroup* cmMakefile::GetSourceGroup(
  const std::vector<std::string>& name) const
{
  cmSourceGroup* sg = nullptr;

  // first look for source group starting with the same as the one we want
  for (cmSourceGroup const& srcGroup : this->SourceGroups) {
    std::string const& sgName = srcGroup.GetName();
    if (sgName == name[0]) {
      sg = const_cast<cmSourceGroup*>(&srcGroup);
      break;
    }
  }

  if (sg != nullptr) {
    // iterate through its children to find match source group
    for (unsigned int i = 1; i < name.size(); ++i) {
      sg = sg->LookupChild(name[i]);
      if (sg == nullptr) {
        break;
      }
    }
  }
  return sg;
}

void cmMakefile::AddSourceGroup(const std::string& name, const char* regex)
{
  std::vector<std::string> nameVector;
  nameVector.push_back(name);
  this->AddSourceGroup(nameVector, regex);
}

void cmMakefile::AddSourceGroup(const std::vector<std::string>& name,
                                const char* regex)
{
  cmSourceGroup* sg = nullptr;
  std::vector<std::string> currentName;
  int i = 0;
  const int lastElement = static_cast<int>(name.size() - 1);
  for (i = lastElement; i >= 0; --i) {
    currentName.assign(name.begin(), name.begin() + i + 1);
    sg = this->GetSourceGroup(currentName);
    if (sg != nullptr) {
      break;
    }
  }

  // i now contains the index of the last found component
  if (i == lastElement) {
    // group already exists, replace its regular expression
    if (regex && sg) {
      // We only want to set the regular expression.  If there are already
      // source files in the group, we don't want to remove them.
      sg->SetGroupRegex(regex);
    }
    return;
  }
  if (i == -1) {
    // group does not exist nor belong to any existing group
    // add its first component
    this->SourceGroups.push_back(cmSourceGroup(name[0], regex));
    sg = this->GetSourceGroup(currentName);
    i = 0; // last component found
  }
  if (!sg) {
    cmSystemTools::Error("Could not create source group ");
    return;
  }
  // build the whole source group path
  for (++i; i <= lastElement; ++i) {
    sg->AddChild(cmSourceGroup(name[i], nullptr, sg->GetFullName().c_str()));
    sg = sg->LookupChild(name[i]);
  }

  sg->SetGroupRegex(regex);
}

cmSourceGroup* cmMakefile::GetOrCreateSourceGroup(
  const std::vector<std::string>& folders)
{
  cmSourceGroup* sg = this->GetSourceGroup(folders);
  if (sg == nullptr) {
    this->AddSourceGroup(folders);
    sg = this->GetSourceGroup(folders);
  }
  return sg;
}

cmSourceGroup* cmMakefile::GetOrCreateSourceGroup(const std::string& name)
{
  const char* delimiter = this->GetDefinition("SOURCE_GROUP_DELIMITER");
  if (delimiter == nullptr) {
    delimiter = "\\";
  }
  return this->GetOrCreateSourceGroup(
    cmSystemTools::tokenize(name, delimiter));
}

/**
 * Find a source group whose regular expression matches the filename
 * part of the given source name.  Search backward through the list of
 * source groups, and take the first matching group found.  This way
 * non-inherited SOURCE_GROUP commands will have precedence over
 * inherited ones.
 */
cmSourceGroup* cmMakefile::FindSourceGroup(
  const char* source, std::vector<cmSourceGroup>& groups) const
{
  // First search for a group that lists the file explicitly.
  for (std::vector<cmSourceGroup>::reverse_iterator sg = groups.rbegin();
       sg != groups.rend(); ++sg) {
    cmSourceGroup* result = sg->MatchChildrenFiles(source);
    if (result) {
      return result;
    }
  }

  // Now search for a group whose regex matches the file.
  for (std::vector<cmSourceGroup>::reverse_iterator sg = groups.rbegin();
       sg != groups.rend(); ++sg) {
    cmSourceGroup* result = sg->MatchChildrenRegex(source);
    if (result) {
      return result;
    }
  }

  // Shouldn't get here, but just in case, return the default group.
  return &groups.front();
}
#endif

static bool mightExpandVariablesCMP0019(const char* s)
{
  return s && *s && strstr(s, "${") && strchr(s, '}');
}

void cmMakefile::ExpandVariablesCMP0019()
{
  // Drop this ancient compatibility behavior with a policy.
  cmPolicies::PolicyStatus pol = this->GetPolicyStatus(cmPolicies::CMP0019);
  if (pol != cmPolicies::OLD && pol != cmPolicies::WARN) {
    return;
  }
  std::ostringstream w;

  const char* includeDirs = this->GetProperty("INCLUDE_DIRECTORIES");
  if (mightExpandVariablesCMP0019(includeDirs)) {
    std::string dirs = includeDirs;
    this->ExpandVariablesInString(dirs, true, true);
    if (pol == cmPolicies::WARN && dirs != includeDirs) {
      /* clang-format off */
      w << "Evaluated directory INCLUDE_DIRECTORIES\n"
        << "  " << includeDirs << "\n"
        << "as\n"
        << "  " << dirs << "\n";
      /* clang-format on */
    }
    this->SetProperty("INCLUDE_DIRECTORIES", dirs.c_str());
  }

  // Also for each target's INCLUDE_DIRECTORIES property:
  for (auto& target : this->Targets) {
    cmTarget& t = target.second;
    if (t.GetType() == cmStateEnums::INTERFACE_LIBRARY ||
        t.GetType() == cmStateEnums::GLOBAL_TARGET) {
      continue;
    }
    includeDirs = t.GetProperty("INCLUDE_DIRECTORIES");
    if (mightExpandVariablesCMP0019(includeDirs)) {
      std::string dirs = includeDirs;
      this->ExpandVariablesInString(dirs, true, true);
      if (pol == cmPolicies::WARN && dirs != includeDirs) {
        /* clang-format off */
        w << "Evaluated target " << t.GetName() << " INCLUDE_DIRECTORIES\n"
          << "  " << includeDirs << "\n"
          << "as\n"
          << "  " << dirs << "\n";
        /* clang-format on */
      }
      t.SetProperty("INCLUDE_DIRECTORIES", dirs.c_str());
    }
  }

  if (const char* linkDirsProp = this->GetProperty("LINK_DIRECTORIES")) {
    if (mightExpandVariablesCMP0019(linkDirsProp)) {
      std::string d = linkDirsProp;
      std::string orig = linkDirsProp;
      this->ExpandVariablesInString(d, true, true);
      if (pol == cmPolicies::WARN && d != orig) {
        /* clang-format off */
        w << "Evaluated link directories\n"
          << "  " << orig << "\n"
          << "as\n"
          << "  " << d << "\n";
        /* clang-format on */
      }
    }
  }

  if (const char* linkLibsProp = this->GetProperty("LINK_LIBRARIES")) {
    std::vector<std::string> linkLibs;
    cmSystemTools::ExpandListArgument(linkLibsProp, linkLibs);

    for (std::vector<std::string>::iterator l = linkLibs.begin();
         l != linkLibs.end(); ++l) {
      std::string libName = *l;
      if (libName == "optimized") {
        ++l;
        libName = *l;
      } else if (libName == "debug") {
        ++l;
        libName = *l;
      }
      if (mightExpandVariablesCMP0019(libName.c_str())) {
        std::string orig = libName;
        this->ExpandVariablesInString(libName, true, true);
        if (pol == cmPolicies::WARN && libName != orig) {
          /* clang-format off */
        w << "Evaluated link library\n"
          << "  " << orig << "\n"
          << "as\n"
          << "  " << libName << "\n";
          /* clang-format on */
        }
      }
    }
  }

  if (!w.str().empty()) {
    std::ostringstream m;
    /* clang-format off */
    m << cmPolicies::GetPolicyWarning(cmPolicies::CMP0019)
      << "\n"
      << "The following variable evaluations were encountered:\n"
      << w.str();
    /* clang-format on */
    this->GetCMakeInstance()->IssueMessage(cmake::AUTHOR_WARNING, m.str(),
                                           this->Backtrace);
  }
}

bool cmMakefile::IsOn(const std::string& name) const
{
  const char* value = this->GetDefinition(name);
  return cmSystemTools::IsOn(value);
}

bool cmMakefile::IsSet(const std::string& name) const
{
  const char* value = this->GetDefinition(name);
  if (!value) {
    return false;
  }

  if (!*value) {
    return false;
  }

  if (cmSystemTools::IsNOTFOUND(value)) {
    return false;
  }

  return true;
}

bool cmMakefile::PlatformIs32Bit() const
{
  if (const char* plat_abi =
        this->GetDefinition("CMAKE_INTERNAL_PLATFORM_ABI")) {
    if (strcmp(plat_abi, "ELF X32") == 0) {
      return false;
    }
  }
  if (const char* sizeof_dptr = this->GetDefinition("CMAKE_SIZEOF_VOID_P")) {
    return atoi(sizeof_dptr) == 4;
  }
  return false;
}

bool cmMakefile::PlatformIs64Bit() const
{
  if (const char* sizeof_dptr = this->GetDefinition("CMAKE_SIZEOF_VOID_P")) {
    return atoi(sizeof_dptr) == 8;
  }
  return false;
}

bool cmMakefile::PlatformIsx32() const
{
  if (const char* plat_abi =
        this->GetDefinition("CMAKE_INTERNAL_PLATFORM_ABI")) {
    if (strcmp(plat_abi, "ELF X32") == 0) {
      return true;
    }
  }
  return false;
}

cmMakefile::AppleSDK cmMakefile::GetAppleSDKType() const
{
  std::string sdkRoot;
  sdkRoot = this->GetSafeDefinition("CMAKE_OSX_SYSROOT");
  sdkRoot = cmSystemTools::LowerCase(sdkRoot);

  struct
  {
    std::string name;
    AppleSDK sdk;
  } const sdkDatabase[]{
    { "appletvos", AppleSDK::AppleTVOS },
    { "appletvsimulator", AppleSDK::AppleTVSimulator },
    { "iphoneos", AppleSDK::IPhoneOS },
    { "iphonesimulator", AppleSDK::IPhoneSimulator },
    { "watchos", AppleSDK::WatchOS },
    { "watchsimulator", AppleSDK::WatchSimulator },
  };

  for (auto entry : sdkDatabase) {
    if (sdkRoot.find(entry.name) == 0 ||
        sdkRoot.find(std::string("/") + entry.name) != std::string::npos) {
      return entry.sdk;
    }
  }

  return AppleSDK::MacOS;
}

bool cmMakefile::PlatformIsAppleEmbedded() const
{
  return GetAppleSDKType() != AppleSDK::MacOS;
}

const char* cmMakefile::GetSONameFlag(const std::string& language) const
{
  std::string name = "CMAKE_SHARED_LIBRARY_SONAME";
  if (!language.empty()) {
    name += "_";
    name += language;
  }
  name += "_FLAG";
  return GetDefinition(name);
}

bool cmMakefile::CanIWriteThisFile(const char* fileName) const
{
  if (!this->IsOn("CMAKE_DISABLE_SOURCE_CHANGES")) {
    return true;
  }
  // If we are doing an in-source build, then the test will always fail
  if (cmSystemTools::SameFile(this->GetHomeDirectory(),
                              this->GetHomeOutputDirectory())) {
    return !this->IsOn("CMAKE_DISABLE_IN_SOURCE_BUILD");
  }

  return !cmSystemTools::IsSubDirectory(fileName, this->GetHomeDirectory()) ||
    cmSystemTools::IsSubDirectory(fileName, this->GetHomeOutputDirectory());
}

const char* cmMakefile::GetRequiredDefinition(const std::string& name) const
{
  const char* ret = this->GetDefinition(name);
  if (!ret) {
    cmSystemTools::Error("Error required internal CMake variable not "
                         "set, cmake may not be built correctly.\n",
                         "Missing variable is:\n", name.c_str());
    return "";
  }
  return ret;
}

bool cmMakefile::IsDefinitionSet(const std::string& name) const
{
  const char* def = this->StateSnapshot.GetDefinition(name);
  if (!def) {
    def = this->GetState()->GetInitializedCacheValue(name);
  }
#ifdef CMAKE_BUILD_WITH_CMAKE
  if (cmVariableWatch* vv = this->GetVariableWatch()) {
    if (!def) {
      vv->VariableAccessed(
        name, cmVariableWatch::UNKNOWN_VARIABLE_DEFINED_ACCESS, def, this);
    }
  }
#endif
  return def != nullptr;
}

const char* cmMakefile::GetDefinition(const std::string& name) const
{
  const char* def = this->StateSnapshot.GetDefinition(name);
  if (!def) {
    def = this->GetState()->GetInitializedCacheValue(name);
  }
#ifdef CMAKE_BUILD_WITH_CMAKE
  cmVariableWatch* vv = this->GetVariableWatch();
  if (vv && !this->SuppressWatches) {
    bool const watch_function_executed = vv->VariableAccessed(
      name, def ? cmVariableWatch::VARIABLE_READ_ACCESS
                : cmVariableWatch::UNKNOWN_VARIABLE_READ_ACCESS,
      def, this);

    if (watch_function_executed) {
      // A callback was executed and may have caused re-allocation of the
      // variable storage.  Look it up again for now.
      // FIXME: Refactor variable storage to avoid this problem.
      def = this->StateSnapshot.GetDefinition(name);
      if (!def) {
        def = this->GetState()->GetInitializedCacheValue(name);
      }
    }
  }
#endif
  return def;
}

const char* cmMakefile::GetSafeDefinition(const std::string& def) const
{
  const char* ret = this->GetDefinition(def);
  if (!ret) {
    return "";
  }
  return ret;
}

std::vector<std::string> cmMakefile::GetDefinitions() const
{
  std::vector<std::string> res = this->StateSnapshot.ClosureKeys();
  std::vector<std::string> cacheKeys = this->GetState()->GetCacheEntryKeys();
  res.insert(res.end(), cacheKeys.begin(), cacheKeys.end());
  std::sort(res.begin(), res.end());
  return res;
}

const char* cmMakefile::ExpandVariablesInString(std::string& source) const
{
  return this->ExpandVariablesInString(source, false, false);
}

const char* cmMakefile::ExpandVariablesInString(
  std::string& source, bool escapeQuotes, bool noEscapes, bool atOnly,
  const char* filename, long line, bool removeEmpty, bool replaceAt) const
{
  bool compareResults = false;
  cmake::MessageType mtype = cmake::LOG;
  std::string errorstr;
  std::string original;

  // Sanity check the @ONLY mode.
  if (atOnly && (!noEscapes || !removeEmpty)) {
    // This case should never be called.  At-only is for
    // configure-file/string which always does no escapes.
    this->IssueMessage(cmake::INTERNAL_ERROR,
                       "ExpandVariablesInString @ONLY called "
                       "on something with escapes.");
    return source.c_str();
  }

  // Variables used in the WARN case.
  std::string newResult;
  std::string newErrorstr;
  cmake::MessageType newError = cmake::LOG;

  switch (this->GetPolicyStatus(cmPolicies::CMP0053)) {
    case cmPolicies::WARN: {
      // Save the original string for the warning.
      original = source;
      newResult = source;
      compareResults = true;
      // Suppress variable watches to avoid calling hooks twice. Suppress new
      // dereferences since the OLD behavior is still what is actually used.
      this->SuppressWatches = true;
      newError = ExpandVariablesInStringNew(
        newErrorstr, newResult, escapeQuotes, noEscapes, atOnly, filename,
        line, removeEmpty, replaceAt);
      this->SuppressWatches = false;
      CM_FALLTHROUGH;
    }
    case cmPolicies::OLD:
      mtype =
        ExpandVariablesInStringOld(errorstr, source, escapeQuotes, noEscapes,
                                   atOnly, filename, line, removeEmpty, true);
      break;
    case cmPolicies::REQUIRED_IF_USED:
    case cmPolicies::REQUIRED_ALWAYS:
    // Messaging here would be *very* verbose.
    case cmPolicies::NEW:
      mtype = ExpandVariablesInStringNew(errorstr, source, escapeQuotes,
                                         noEscapes, atOnly, filename, line,
                                         removeEmpty, replaceAt);
      break;
  }

  // If it's an error in either case, just report the error...
  if (mtype != cmake::LOG) {
    if (mtype == cmake::FATAL_ERROR) {
      cmSystemTools::SetFatalErrorOccured();
    }
    this->IssueMessage(mtype, errorstr);
  }
  // ...otherwise, see if there's a difference that needs to be warned about.
  else if (compareResults && (newResult != source || newError != mtype)) {
    std::string msg = cmPolicies::GetPolicyWarning(cmPolicies::CMP0053);
    msg += "\n";

    std::string msg_input = original;
    cmSystemTools::ReplaceString(msg_input, "\n", "\n  ");
    msg += "For input:\n  '";
    msg += msg_input;
    msg += "'\n";

    std::string msg_old = source;
    cmSystemTools::ReplaceString(msg_old, "\n", "\n  ");
    msg += "the old evaluation rules produce:\n  '";
    msg += msg_old;
    msg += "'\n";

    if (newError == mtype) {
      std::string msg_new = newResult;
      cmSystemTools::ReplaceString(msg_new, "\n", "\n  ");
      msg += "but the new evaluation rules produce:\n  '";
      msg += msg_new;
      msg += "'\n";
    } else {
      std::string msg_err = newErrorstr;
      cmSystemTools::ReplaceString(msg_err, "\n", "\n  ");
      msg += "but the new evaluation rules produce an error:\n  ";
      msg += msg_err;
      msg += "\n";
    }

    msg +=
      "Using the old result for compatibility since the policy is not set.";

    this->IssueMessage(cmake::AUTHOR_WARNING, msg);
  }

  return source.c_str();
}

cmake::MessageType cmMakefile::ExpandVariablesInStringOld(
  std::string& errorstr, std::string& source, bool escapeQuotes,
  bool noEscapes, bool atOnly, const char* filename, long line,
  bool removeEmpty, bool replaceAt) const
{
  // Fast path strings without any special characters.
  if (source.find_first_of("$@\\") == std::string::npos) {
    return cmake::LOG;
  }

  // Special-case the @ONLY mode.
  if (atOnly) {
    // Store an original copy of the input.
    std::string input = source;

    // Start with empty output.
    source.clear();

    // Look for one @VAR@ at a time.
    const char* in = input.c_str();
    while (this->cmAtVarRegex.find(in)) {
      // Get the range of the string to replace.
      const char* first = in + this->cmAtVarRegex.start();
      const char* last = in + this->cmAtVarRegex.end();

      // Store the unchanged part of the string now.
      source.append(in, first - in);

      // Lookup the definition of VAR.
      std::string var(first + 1, last - first - 2);
      if (const char* val = this->GetDefinition(var)) {
        // Store the value in the output escaping as requested.
        if (escapeQuotes) {
          source.append(cmSystemTools::EscapeQuotes(val));
        } else {
          source.append(val);
        }
      }

      // Continue looking for @VAR@ further along the string.
      in = last;
    }

    // Append the rest of the unchanged part of the string.
    source.append(in);

    return cmake::LOG;
  }

  // This method replaces ${VAR} and @VAR@ where VAR is looked up
  // with GetDefinition(), if not found in the map, nothing is expanded.
  // It also supports the $ENV{VAR} syntax where VAR is looked up in
  // the current environment variables.

  cmCommandArgumentParserHelper parser;
  parser.SetMakefile(this);
  parser.SetLineFile(line, filename);
  parser.SetEscapeQuotes(escapeQuotes);
  parser.SetNoEscapeMode(noEscapes);
  parser.SetReplaceAtSyntax(replaceAt);
  parser.SetRemoveEmpty(removeEmpty);
  int res = parser.ParseString(source.c_str(), 0);
  const char* emsg = parser.GetError();
  cmake::MessageType mtype = cmake::LOG;
  if (res && !emsg[0]) {
    source = parser.GetResult();
  } else {
    // Construct the main error message.
    std::ostringstream error;
    error << "Syntax error in cmake code ";
    if (filename && line > 0) {
      // This filename and line number may be more specific than the
      // command context because one command invocation can have
      // arguments on multiple lines.
      error << "at\n"
            << "  " << filename << ":" << line << "\n";
    }
    error << "when parsing string\n"
          << "  " << source << "\n";
    error << emsg;

    // If the parser failed ("res" is false) then this is a real
    // argument parsing error, so the policy applies.  Otherwise the
    // parser reported an error message without failing because the
    // helper implementation is unhappy, which has always reported an
    // error.
    mtype = cmake::FATAL_ERROR;
    if (!res) {
      // This is a real argument parsing error.  Use policy CMP0010 to
      // decide whether it is an error.
      switch (this->GetPolicyStatus(cmPolicies::CMP0010)) {
        case cmPolicies::WARN:
          error << "\n" << cmPolicies::GetPolicyWarning(cmPolicies::CMP0010);
          CM_FALLTHROUGH;
        case cmPolicies::OLD:
          // OLD behavior is to just warn and continue.
          mtype = cmake::AUTHOR_WARNING;
          break;
        case cmPolicies::REQUIRED_IF_USED:
        case cmPolicies::REQUIRED_ALWAYS:
          error << "\n"
                << cmPolicies::GetRequiredPolicyError(cmPolicies::CMP0010);
        case cmPolicies::NEW:
          // NEW behavior is to report the error.
          break;
      }
    }
    errorstr = error.str();
  }
  return mtype;
}

typedef enum { NORMAL, ENVIRONMENT, CACHE } t_domain;
struct t_lookup
{
  t_lookup()
    : domain(NORMAL)
    , loc(0)
  {
  }
  t_domain domain;
  size_t loc;
};

cmake::MessageType cmMakefile::ExpandVariablesInStringNew(
  std::string& errorstr, std::string& source, bool escapeQuotes,
  bool noEscapes, bool atOnly, const char* filename, long line,
  bool removeEmpty, bool replaceAt) const
{
  // This method replaces ${VAR} and @VAR@ where VAR is looked up
  // with GetDefinition(), if not found in the map, nothing is expanded.
  // It also supports the $ENV{VAR} syntax where VAR is looked up in
  // the current environment variables.

  const char* in = source.c_str();
  const char* last = in;
  std::string result;
  result.reserve(source.size());
  std::vector<t_lookup> openstack;
  bool error = false;
  bool done = false;
  cmake::MessageType mtype = cmake::LOG;

  cmState* state = this->GetCMakeInstance()->GetState();

  do {
    char inc = *in;
    switch (inc) {
      case '}':
        if (!openstack.empty()) {
          t_lookup var = openstack.back();
          openstack.pop_back();
          result.append(last, in - last);
          std::string const& lookup = result.substr(var.loc);
          const char* value = nullptr;
          std::string varresult;
          std::string svalue;
          static const std::string lineVar = "CMAKE_CURRENT_LIST_LINE";
          switch (var.domain) {
            case NORMAL:
              if (filename && lookup == lineVar) {
                std::ostringstream ostr;
                ostr << line;
                varresult = ostr.str();
              } else {
                value = this->GetDefinition(lookup);
              }
              break;
            case ENVIRONMENT:
              if (cmSystemTools::GetEnv(lookup, svalue)) {
                value = svalue.c_str();
              }
              break;
            case CACHE:
              value = state->GetCacheEntryValue(lookup);
              break;
          }
          // Get the string we're meant to append to.
          if (value) {
            if (escapeQuotes) {
              varresult = cmSystemTools::EscapeQuotes(value);
            } else {
              varresult = value;
            }
          } else if (!removeEmpty) {
            // check to see if we need to print a warning
            // if strict mode is on and the variable has
            // not been "cleared"/initialized with a set(foo ) call
            if (this->GetCMakeInstance()->GetWarnUninitialized() &&
                !this->VariableInitialized(lookup)) {
              if (this->CheckSystemVars ||
                  cmSystemTools::IsSubDirectory(filename,
                                                this->GetHomeDirectory()) ||
                  cmSystemTools::IsSubDirectory(
                    filename, this->GetHomeOutputDirectory())) {
                std::ostringstream msg;
                msg << "uninitialized variable \'" << lookup << "\'";
                this->IssueMessage(cmake::AUTHOR_WARNING, msg.str());
              }
            }
          }
          result.replace(var.loc, result.size() - var.loc, varresult);
          // Start looking from here on out.
          last = in + 1;
        }
        break;
      case '$':
        if (!atOnly) {
          t_lookup lookup;
          const char* next = in + 1;
          const char* start = nullptr;
          char nextc = *next;
          if (nextc == '{') {
            // Looking for a variable.
            start = in + 2;
            lookup.domain = NORMAL;
          } else if (nextc == '<') {
          } else if (!nextc) {
            result.append(last, next - last);
            last = next;
          } else if (cmHasLiteralPrefix(next, "ENV{")) {
            // Looking for an environment variable.
            start = in + 5;
            lookup.domain = ENVIRONMENT;
          } else if (cmHasLiteralPrefix(next, "CACHE{")) {
            // Looking for a cache variable.
            start = in + 7;
            lookup.domain = CACHE;
          } else {
            if (this->cmNamedCurly.find(next)) {
              errorstr = "Syntax $" +
                std::string(next, this->cmNamedCurly.end()) +
                "{} is not supported.  Only ${}, $ENV{}, "
                "and $CACHE{} are allowed.";
              mtype = cmake::FATAL_ERROR;
              error = true;
            }
          }
          if (start) {
            result.append(last, in - last);
            last = start;
            in = start - 1;
            lookup.loc = result.size();
            openstack.push_back(lookup);
          }
          break;
        }
        CM_FALLTHROUGH;
      case '\\':
        if (!noEscapes) {
          const char* next = in + 1;
          char nextc = *next;
          if (nextc == 't') {
            result.append(last, in - last);
            result.append("\t");
            last = next + 1;
          } else if (nextc == 'n') {
            result.append(last, in - last);
            result.append("\n");
            last = next + 1;
          } else if (nextc == 'r') {
            result.append(last, in - last);
            result.append("\r");
            last = next + 1;
          } else if (nextc == ';' && openstack.empty()) {
            // Handled in ExpandListArgument; pass the backslash literally.
          } else if (isalnum(nextc) || nextc == '\0') {
            errorstr += "Invalid character escape '\\";
            if (nextc) {
              errorstr += nextc;
              errorstr += "'.";
            } else {
              errorstr += "' (at end of input).";
            }
            error = true;
          } else {
            // Take what we've found so far, skipping the escape character.
            result.append(last, in - last);
            // Start tracking from the next character.
            last = in + 1;
          }
          // Skip the next character since it was escaped, but don't read past
          // the end of the string.
          if (*last) {
            ++in;
          }
        }
        break;
      case '\n':
        // Onto the next line.
        ++line;
        break;
      case '\0':
        done = true;
        break;
      case '@':
        if (replaceAt) {
          const char* nextAt = strchr(in + 1, '@');
          if (nextAt && nextAt != in + 1 &&
              nextAt ==
                in + 1 + strspn(in + 1, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
                                        "abcdefghijklmnopqrstuvwxyz"
                                        "0123456789/_.+-")) {
            std::string variable(in + 1, nextAt - in - 1);
            std::string varresult = this->GetSafeDefinition(variable);
            if (escapeQuotes) {
              varresult = cmSystemTools::EscapeQuotes(varresult);
            }
            // Skip over the variable.
            result.append(last, in - last);
            result.append(varresult);
            in = nextAt;
            last = in + 1;
            break;
          }
        }
      // Failed to find a valid @ expansion; treat it as literal.
      /* FALLTHROUGH */
      default: {
        if (!openstack.empty() &&
            !(isalnum(inc) || inc == '_' || inc == '/' || inc == '.' ||
              inc == '+' || inc == '-')) {
          errorstr += "Invalid character (\'";
          errorstr += inc;
          result.append(last, in - last);
          errorstr += "\') in a variable name: "
                      "'" +
            result.substr(openstack.back().loc) + "'";
          mtype = cmake::FATAL_ERROR;
          error = true;
        }
        break;
      }
    }
    // Look at the next character.
  } while (!error && !done && *++in);

  // Check for open variable references yet.
  if (!error && !openstack.empty()) {
    // There's an open variable reference waiting.  Policy CMP0010 flags
    // whether this is an error or not.  The new parser now enforces
    // CMP0010 as well.
    errorstr += "There is an unterminated variable reference.";
    error = true;
  }

  if (error) {
    std::ostringstream emsg;
    emsg << "Syntax error in cmake code ";
    if (filename) {
      // This filename and line number may be more specific than the
      // command context because one command invocation can have
      // arguments on multiple lines.
      emsg << "at\n"
           << "  " << filename << ":" << line << "\n";
    }
    emsg << "when parsing string\n"
         << "  " << source << "\n";
    emsg << errorstr;
    mtype = cmake::FATAL_ERROR;
    errorstr = emsg.str();
  } else {
    // Append the rest of the unchanged part of the string.
    result.append(last);

    source = result;
  }

  return mtype;
}

void cmMakefile::RemoveVariablesInString(std::string& source,
                                         bool atOnly) const
{
  if (!atOnly) {
    cmsys::RegularExpression var("(\\${[A-Za-z_0-9]*})");
    while (var.find(source)) {
      source.erase(var.start(), var.end() - var.start());
    }
  }

  if (!atOnly) {
    cmsys::RegularExpression varb("(\\$ENV{[A-Za-z_0-9]*})");
    while (varb.find(source)) {
      source.erase(varb.start(), varb.end() - varb.start());
    }
  }
  cmsys::RegularExpression var2("(@[A-Za-z_0-9]*@)");
  while (var2.find(source)) {
    source.erase(var2.start(), var2.end() - var2.start());
  }
}

std::string cmMakefile::GetConfigurations(std::vector<std::string>& configs,
                                          bool singleConfig) const
{
  if (this->GetGlobalGenerator()->IsMultiConfig()) {
    if (const char* configTypes =
          this->GetDefinition("CMAKE_CONFIGURATION_TYPES")) {
      cmSystemTools::ExpandListArgument(configTypes, configs);
    }
    return "";
  }
  const std::string& buildType = this->GetSafeDefinition("CMAKE_BUILD_TYPE");
  if (singleConfig && !buildType.empty()) {
    configs.push_back(buildType);
  }
  return buildType;
}

bool cmMakefile::IsFunctionBlocked(const cmListFileFunction& lff,
                                   cmExecutionStatus& status)
{
  // if there are no blockers get out of here
  if (this->FunctionBlockers.begin() == this->FunctionBlockers.end()) {
    return false;
  }

  // loop over all function blockers to see if any block this command
  // evaluate in reverse, this is critical for balanced IF statements etc
  std::vector<cmFunctionBlocker*>::reverse_iterator pos;
  for (pos = this->FunctionBlockers.rbegin();
       pos != this->FunctionBlockers.rend(); ++pos) {
    if ((*pos)->IsFunctionBlocked(lff, *this, status)) {
      return true;
    }
  }

  return false;
}

void cmMakefile::PushFunctionBlockerBarrier()
{
  this->FunctionBlockerBarriers.push_back(this->FunctionBlockers.size());
}

void cmMakefile::PopFunctionBlockerBarrier(bool reportError)
{
  // Remove any extra entries pushed on the barrier.
  FunctionBlockersType::size_type barrier =
    this->FunctionBlockerBarriers.back();
  while (this->FunctionBlockers.size() > barrier) {
    std::unique_ptr<cmFunctionBlocker> fb(this->FunctionBlockers.back());
    this->FunctionBlockers.pop_back();
    if (reportError) {
      // Report the context in which the unclosed block was opened.
      cmListFileContext const& lfc = fb->GetStartingContext();
      std::ostringstream e;
      /* clang-format off */
      e << "A logical block opening on the line\n"
        << "  " << lfc << "\n"
        << "is not closed.";
      /* clang-format on */
      this->IssueMessage(cmake::FATAL_ERROR, e.str());
      reportError = false;
    }
  }

  // Remove the barrier.
  this->FunctionBlockerBarriers.pop_back();
}

void cmMakefile::PushLoopBlock()
{
  assert(!this->LoopBlockCounter.empty());
  this->LoopBlockCounter.top()++;
}

void cmMakefile::PopLoopBlock()
{
  assert(!this->LoopBlockCounter.empty());
  assert(this->LoopBlockCounter.top() > 0);
  this->LoopBlockCounter.top()--;
}

void cmMakefile::PushLoopBlockBarrier()
{
  this->LoopBlockCounter.push(0);
}

void cmMakefile::PopLoopBlockBarrier()
{
  assert(!this->LoopBlockCounter.empty());
  assert(this->LoopBlockCounter.top() == 0);
  this->LoopBlockCounter.pop();
}

bool cmMakefile::IsLoopBlock() const
{
  assert(!this->LoopBlockCounter.empty());
  return !this->LoopBlockCounter.empty() && this->LoopBlockCounter.top() > 0;
}

std::string cmMakefile::GetExecutionFilePath() const
{
  assert(this->StateSnapshot.IsValid());
  return this->StateSnapshot.GetExecutionListFile();
}

bool cmMakefile::ExpandArguments(std::vector<cmListFileArgument> const& inArgs,
                                 std::vector<std::string>& outArgs,
                                 const char* filename) const
{
  std::string efp = this->GetExecutionFilePath();
  if (!filename) {
    filename = efp.c_str();
  }
  std::string value;
  outArgs.reserve(inArgs.size());
  for (cmListFileArgument const& i : inArgs) {
    // No expansion in a bracket argument.
    if (i.Delim == cmListFileArgument::Bracket) {
      outArgs.push_back(i.Value);
      continue;
    }
    // Expand the variables in the argument.
    value = i.Value;
    this->ExpandVariablesInString(value, false, false, false, filename, i.Line,
                                  false, false);

    // If the argument is quoted, it should be one argument.
    // Otherwise, it may be a list of arguments.
    if (i.Delim == cmListFileArgument::Quoted) {
      outArgs.push_back(value);
    } else {
      cmSystemTools::ExpandListArgument(value, outArgs);
    }
  }
  return !cmSystemTools::GetFatalErrorOccured();
}

bool cmMakefile::ExpandArguments(
  std::vector<cmListFileArgument> const& inArgs,
  std::vector<cmExpandedCommandArgument>& outArgs, const char* filename) const
{
  std::string efp = this->GetExecutionFilePath();
  if (!filename) {
    filename = efp.c_str();
  }
  std::string value;
  outArgs.reserve(inArgs.size());
  for (cmListFileArgument const& i : inArgs) {
    // No expansion in a bracket argument.
    if (i.Delim == cmListFileArgument::Bracket) {
      outArgs.push_back(cmExpandedCommandArgument(i.Value, true));
      continue;
    }
    // Expand the variables in the argument.
    value = i.Value;
    this->ExpandVariablesInString(value, false, false, false, filename, i.Line,
                                  false, false);

    // If the argument is quoted, it should be one argument.
    // Otherwise, it may be a list of arguments.
    if (i.Delim == cmListFileArgument::Quoted) {
      outArgs.push_back(cmExpandedCommandArgument(value, true));
    } else {
      std::vector<std::string> stringArgs;
      cmSystemTools::ExpandListArgument(value, stringArgs);
      for (std::string const& stringArg : stringArgs) {
        outArgs.push_back(cmExpandedCommandArgument(stringArg, false));
      }
    }
  }
  return !cmSystemTools::GetFatalErrorOccured();
}

void cmMakefile::AddFunctionBlocker(cmFunctionBlocker* fb)
{
  if (!this->ExecutionStatusStack.empty()) {
    // Record the context in which the blocker is created.
    fb->SetStartingContext(this->GetExecutionContext());
  }

  this->FunctionBlockers.push_back(fb);
}

std::unique_ptr<cmFunctionBlocker> cmMakefile::RemoveFunctionBlocker(
  cmFunctionBlocker* fb, const cmListFileFunction& lff)
{
  // Find the function blocker stack barrier for the current scope.
  // We only remove a blocker whose index is not less than the barrier.
  FunctionBlockersType::size_type barrier = 0;
  if (!this->FunctionBlockerBarriers.empty()) {
    barrier = this->FunctionBlockerBarriers.back();
  }

  // Search for the function blocker whose scope this command ends.
  for (FunctionBlockersType::size_type i = this->FunctionBlockers.size();
       i > barrier; --i) {
    std::vector<cmFunctionBlocker*>::iterator pos =
      this->FunctionBlockers.begin() + (i - 1);
    if (*pos == fb) {
      // Warn if the arguments do not match, but always remove.
      if (!(*pos)->ShouldRemove(lff, *this)) {
        cmListFileContext const& lfc = fb->GetStartingContext();
        cmListFileContext closingContext =
          cmListFileContext::FromCommandContext(lff, lfc.FilePath);
        std::ostringstream e;
        /* clang-format off */
        e << "A logical block opening on the line\n"
          << "  " << lfc << "\n"
          << "closes on the line\n"
          << "  " << closingContext << "\n"
          << "with mis-matching arguments.";
        /* clang-format on */
        this->IssueMessage(cmake::AUTHOR_WARNING, e.str());
      }
      cmFunctionBlocker* b = *pos;
      this->FunctionBlockers.erase(pos);
      return std::unique_ptr<cmFunctionBlocker>(b);
    }
  }

  return std::unique_ptr<cmFunctionBlocker>();
}

const char* cmMakefile::GetHomeDirectory() const
{
  return this->GetCMakeInstance()->GetHomeDirectory();
}

const char* cmMakefile::GetHomeOutputDirectory() const
{
  return this->GetCMakeInstance()->GetHomeOutputDirectory();
}

void cmMakefile::SetScriptModeFile(const char* scriptfile)
{
  this->AddDefinition("CMAKE_SCRIPT_MODE_FILE", scriptfile);
}

void cmMakefile::SetArgcArgv(const std::vector<std::string>& args)
{
  std::ostringstream strStream;
  strStream << args.size();
  this->AddDefinition("CMAKE_ARGC", strStream.str().c_str());
  // this->MarkVariableAsUsed("CMAKE_ARGC");

  for (unsigned int t = 0; t < args.size(); ++t) {
    std::ostringstream tmpStream;
    tmpStream << "CMAKE_ARGV" << t;
    this->AddDefinition(tmpStream.str(), args[t].c_str());
    // this->MarkVariableAsUsed(tmpStream.str().c_str());
  }
}

cmSourceFile* cmMakefile::GetSource(const std::string& sourceName) const
{
  cmSourceFileLocation sfl(this, sourceName);
  auto name = this->GetCMakeInstance()->StripExtension(sfl.GetName());
#if defined(_WIN32) || defined(__APPLE__)
  name = cmSystemTools::LowerCase(name);
#endif
  auto sfsi = this->SourceFileSearchIndex.find(name);
  if (sfsi != this->SourceFileSearchIndex.end()) {
    for (auto sf : sfsi->second) {
      if (sf->Matches(sfl)) {
        return sf;
      }
    }
  }
  return nullptr;
}

cmSourceFile* cmMakefile::CreateSource(const std::string& sourceName,
                                       bool generated)
{
  cmSourceFile* sf = new cmSourceFile(this, sourceName);
  if (generated) {
    sf->SetProperty("GENERATED", "1");
  }
  this->SourceFiles.push_back(sf);

  auto name =
    this->GetCMakeInstance()->StripExtension(sf->GetLocation().GetName());
#if defined(_WIN32) || defined(__APPLE__)
  name = cmSystemTools::LowerCase(name);
#endif
  this->SourceFileSearchIndex[name].push_back(sf);

  return sf;
}

cmSourceFile* cmMakefile::GetOrCreateSource(const std::string& sourceName,
                                            bool generated)
{
  if (cmSourceFile* esf = this->GetSource(sourceName)) {
    return esf;
  }
  return this->CreateSource(sourceName, generated);
}

void cmMakefile::AddTargetObject(std::string const& tgtName,
                                 std::string const& objFile)
{
  cmSourceFile* sf = this->GetOrCreateSource(objFile, true);
  sf->SetObjectLibrary(tgtName);
  sf->SetProperty("EXTERNAL_OBJECT", "1");
#if defined(CMAKE_BUILD_WITH_CMAKE)
  this->SourceGroups[this->ObjectLibrariesSourceGroupIndex].AddGroupFile(
    sf->GetFullPath());
#endif
}

void cmMakefile::EnableLanguage(std::vector<std::string> const& lang,
                                bool optional)
{
  this->AddDefinition("CMAKE_CFG_INTDIR",
                      this->GetGlobalGenerator()->GetCMakeCFGIntDir());
  // If RC is explicitly listed we need to do it after other languages.
  // On some platforms we enable RC implicitly while enabling others.
  // Do not let that look like recursive enable_language(RC).
  std::vector<std::string> langs;
  std::vector<std::string> langsRC;
  langs.reserve(lang.size());
  for (std::string const& i : lang) {
    if (i == "RC") {
      langsRC.push_back(i);
    } else {
      langs.push_back(i);
    }
  }
  if (!langs.empty()) {
    this->GetGlobalGenerator()->EnableLanguage(langs, this, optional);
  }
  if (!langsRC.empty()) {
    this->GetGlobalGenerator()->EnableLanguage(langsRC, this, optional);
  }
}

int cmMakefile::TryCompile(const std::string& srcdir,
                           const std::string& bindir,
                           const std::string& projectName,
                           const std::string& targetName, bool fast,
                           const std::vector<std::string>* cmakeArgs,
                           std::string& output)
{
  this->IsSourceFileTryCompile = fast;
  // does the binary directory exist ? If not create it...
  if (!cmSystemTools::FileIsDirectory(bindir)) {
    cmSystemTools::MakeDirectory(bindir.c_str());
  }

  // change to the tests directory and run cmake
  // use the cmake object instead of calling cmake
  cmWorkingDirectory workdir(bindir);

  // make sure the same generator is used
  // use this program as the cmake to be run, it should not
  // be run that way but the cmake object requires a vailid path
  cmake cm(cmake::RoleProject);
  cm.SetIsInTryCompile(true);
  cmGlobalGenerator* gg =
    cm.CreateGlobalGenerator(this->GetGlobalGenerator()->GetName());
  if (!gg) {
    this->IssueMessage(cmake::INTERNAL_ERROR, "Global generator '" +
                         this->GetGlobalGenerator()->GetName() +
                         "' could not be created.");
    cmSystemTools::SetFatalErrorOccured();
    this->IsSourceFileTryCompile = false;
    return 1;
  }
  cm.SetGlobalGenerator(gg);

  // do a configure
  cm.SetHomeDirectory(srcdir);
  cm.SetHomeOutputDirectory(bindir);
  cm.SetGeneratorInstance(this->GetSafeDefinition("CMAKE_GENERATOR_INSTANCE"));
  cm.SetGeneratorPlatform(this->GetSafeDefinition("CMAKE_GENERATOR_PLATFORM"));
  cm.SetGeneratorToolset(this->GetSafeDefinition("CMAKE_GENERATOR_TOOLSET"));
  cm.LoadCache();
  if (!gg->IsMultiConfig()) {
    if (const char* config =
          this->GetDefinition("CMAKE_TRY_COMPILE_CONFIGURATION")) {
      // Tell the single-configuration generator which one to use.
      // Add this before the user-provided CMake arguments in case
      // one of the arguments is -DCMAKE_BUILD_TYPE=...
      cm.AddCacheEntry("CMAKE_BUILD_TYPE", config, "Build configuration",
                       cmStateEnums::STRING);
    }
  }
  // if cmake args were provided then pass them in
  if (cmakeArgs) {
    // FIXME: Workaround to ignore unused CLI variables in try-compile.
    //
    // Ideally we should use SetArgs to honor options like --warn-unused-vars.
    // However, there is a subtle problem when certain arguments are passed to
    // a macro wrapping around try_compile or try_run that does not escape
    // semicolons in its parameters but just passes ${ARGV} or ${ARGN}.  In
    // this case a list argument like "-DVAR=a;b" gets split into multiple
    // cmake arguments "-DVAR=a" and "b".  Currently SetCacheArgs ignores
    // argument "b" and uses just "-DVAR=a", leading to a subtle bug in that
    // the try_compile or try_run does not get the proper value of VAR.  If we
    // call SetArgs here then it would treat "b" as the source directory and
    // cause an error such as "The source directory .../CMakeFiles/CMakeTmp/b
    // does not exist", thus breaking the try_compile or try_run completely.
    //
    // Strictly speaking the bug is in the wrapper macro because the CMake
    // language has always flattened nested lists and the macro should escape
    // the semicolons in its arguments before forwarding them.  However, this
    // bug is so subtle that projects typically work anyway, usually because
    // the value VAR=a is sufficient for the try_compile or try_run to get the
    // correct result.  Calling SetArgs here would break such projects that
    // previously built.  Instead we work around the issue by never reporting
    // unused arguments and ignoring options such as --warn-unused-vars.
    cm.SetWarnUnusedCli(false);
    // cm.SetArgs(*cmakeArgs, true);

    cm.SetCacheArgs(*cmakeArgs);
  }
  // to save time we pass the EnableLanguage info directly
  gg->EnableLanguagesFromGenerator(this->GetGlobalGenerator(), this);
  if (this->IsOn("CMAKE_SUPPRESS_DEVELOPER_WARNINGS")) {
    cm.AddCacheEntry("CMAKE_SUPPRESS_DEVELOPER_WARNINGS", "TRUE", "",
                     cmStateEnums::INTERNAL);
  } else {
    cm.AddCacheEntry("CMAKE_SUPPRESS_DEVELOPER_WARNINGS", "FALSE", "",
                     cmStateEnums::INTERNAL);
  }
  if (cm.Configure() != 0) {
    this->IssueMessage(cmake::FATAL_ERROR,
                       "Failed to configure test project build system.");
    cmSystemTools::SetFatalErrorOccured();
    this->IsSourceFileTryCompile = false;
    return 1;
  }

  if (cm.Generate() != 0) {
    this->IssueMessage(cmake::FATAL_ERROR,
                       "Failed to generate test project build system.");
    cmSystemTools::SetFatalErrorOccured();
    this->IsSourceFileTryCompile = false;
    return 1;
  }

  // finally call the generator to actually build the resulting project
  int ret = this->GetGlobalGenerator()->TryCompile(
    srcdir, bindir, projectName, targetName, fast, output, this);

  this->IsSourceFileTryCompile = false;
  return ret;
}

bool cmMakefile::GetIsSourceFileTryCompile() const
{
  return this->IsSourceFileTryCompile;
}

cmake* cmMakefile::GetCMakeInstance() const
{
  return this->GlobalGenerator->GetCMakeInstance();
}

cmMessenger* cmMakefile::GetMessenger() const
{
  return this->GetCMakeInstance()->GetMessenger();
}

cmGlobalGenerator* cmMakefile::GetGlobalGenerator() const
{
  return this->GlobalGenerator;
}

#ifdef CMAKE_BUILD_WITH_CMAKE
cmVariableWatch* cmMakefile::GetVariableWatch() const
{
  if (this->GetCMakeInstance() &&
      this->GetCMakeInstance()->GetVariableWatch()) {
    return this->GetCMakeInstance()->GetVariableWatch();
  }
  return nullptr;
}
#endif

cmState* cmMakefile::GetState() const
{
  return this->GetCMakeInstance()->GetState();
}

void cmMakefile::DisplayStatus(const char* message, float s) const
{
  cmake* cm = this->GetCMakeInstance();
  if (cm->GetWorkingMode() == cmake::FIND_PACKAGE_MODE) {
    // don't output any STATUS message in FIND_PACKAGE_MODE, since they will
    // directly be fed to the compiler, which will be confused.
    return;
  }
  cm->UpdateProgress(message, s);
}

std::string cmMakefile::GetModulesFile(const char* filename) const
{
  std::string result;

  // We search the module always in CMAKE_ROOT and in CMAKE_MODULE_PATH,
  // and then decide based on the policy setting which one to return.
  // See CMP0017 for more details.
  // The specific problem was that KDE 4.5.0 installs a
  // FindPackageHandleStandardArgs.cmake which doesn't have the new features
  // of FPHSA.cmake introduced in CMake 2.8.3 yet, and by setting
  // CMAKE_MODULE_PATH also e.g. FindZLIB.cmake from cmake included
  // FPHSA.cmake from kdelibs and not from CMake, and tried to use the
  // new features, which were not there in the version from kdelibs, and so
  // failed ("
  std::string moduleInCMakeRoot;
  std::string moduleInCMakeModulePath;

  // Always search in CMAKE_MODULE_PATH:
  const char* cmakeModulePath = this->GetDefinition("CMAKE_MODULE_PATH");
  if (cmakeModulePath) {
    std::vector<std::string> modulePath;
    cmSystemTools::ExpandListArgument(cmakeModulePath, modulePath);

    // Look through the possible module directories.
    for (std::string itempl : modulePath) {
      cmSystemTools::ConvertToUnixSlashes(itempl);
      itempl += "/";
      itempl += filename;
      if (cmSystemTools::FileExists(itempl.c_str())) {
        moduleInCMakeModulePath = itempl;
        break;
      }
    }
  }

  // Always search in the standard modules location.
  moduleInCMakeRoot = cmSystemTools::GetCMakeRoot();
  moduleInCMakeRoot += "/Modules/";
  moduleInCMakeRoot += filename;
  cmSystemTools::ConvertToUnixSlashes(moduleInCMakeRoot);
  if (!cmSystemTools::FileExists(moduleInCMakeRoot.c_str())) {
    moduleInCMakeRoot.clear();
  }

  // Normally, prefer the files found in CMAKE_MODULE_PATH. Only when the file
  // from which we are being called is located itself in CMAKE_ROOT, then
  // prefer results from CMAKE_ROOT depending on the policy setting.
  result = moduleInCMakeModulePath;
  if (result.empty()) {
    result = moduleInCMakeRoot;
  }

  if (!moduleInCMakeModulePath.empty() && !moduleInCMakeRoot.empty()) {
    const char* currentFile = this->GetDefinition("CMAKE_CURRENT_LIST_FILE");
    std::string mods = cmSystemTools::GetCMakeRoot() + "/Modules/";
    if (currentFile && cmSystemTools::IsSubDirectory(currentFile, mods)) {
      switch (this->GetPolicyStatus(cmPolicies::CMP0017)) {
        case cmPolicies::WARN: {
          std::ostringstream e;
          /* clang-format off */
          e << "File " << currentFile << " includes "
            << moduleInCMakeModulePath
            << " (found via CMAKE_MODULE_PATH) which shadows "
            << moduleInCMakeRoot  << ". This may cause errors later on .\n"
            << cmPolicies::GetPolicyWarning(cmPolicies::CMP0017);
          /* clang-format on */

          this->IssueMessage(cmake::AUTHOR_WARNING, e.str());
          CM_FALLTHROUGH;
        }
        case cmPolicies::OLD:
          result = moduleInCMakeModulePath;
          break;
        case cmPolicies::REQUIRED_IF_USED:
        case cmPolicies::REQUIRED_ALWAYS:
        case cmPolicies::NEW:
          result = moduleInCMakeRoot;
          break;
      }
    }
  }

  return result;
}

void cmMakefile::ConfigureString(const std::string& input, std::string& output,
                                 bool atOnly, bool escapeQuotes) const
{
  // Split input to handle one line at a time.
  std::string::const_iterator lineStart = input.begin();
  while (lineStart != input.end()) {
    // Find the end of this line.
    std::string::const_iterator lineEnd = lineStart;
    while (lineEnd != input.end() && *lineEnd != '\n') {
      ++lineEnd;
    }

    // Copy the line.
    std::string line(lineStart, lineEnd);

    // Skip the newline character.
    bool haveNewline = (lineEnd != input.end());
    if (haveNewline) {
      ++lineEnd;
    }

    // Replace #cmakedefine instances.
    if (this->cmDefineRegex.find(line)) {
      const char* def = this->GetDefinition(this->cmDefineRegex.match(2));
      if (!cmSystemTools::IsOff(def)) {
        const std::string indentation = this->cmDefineRegex.match(1);
        cmSystemTools::ReplaceString(line, "#" + indentation + "cmakedefine",
                                     "#" + indentation + "define");
        output += line;
      } else {
        output += "/* #undef ";
        output += this->cmDefineRegex.match(2);
        output += " */";
      }
    } else if (this->cmDefine01Regex.find(line)) {
      const std::string indentation = this->cmDefine01Regex.match(1);
      const char* def = this->GetDefinition(this->cmDefine01Regex.match(2));
      cmSystemTools::ReplaceString(line, "#" + indentation + "cmakedefine01",
                                   "#" + indentation + "define");
      output += line;
      if (!cmSystemTools::IsOff(def)) {
        output += " 1";
      } else {
        output += " 0";
      }
    } else {
      output += line;
    }

    if (haveNewline) {
      output += "\n";
    }

    // Move to the next line.
    lineStart = lineEnd;
  }

  // Perform variable replacements.
  this->ExpandVariablesInString(output, escapeQuotes, true, atOnly, nullptr,
                                -1, true, true);
}

int cmMakefile::ConfigureFile(const char* infile, const char* outfile,
                              bool copyonly, bool atOnly, bool escapeQuotes,
                              cmNewLineStyle newLine)
{
  int res = 1;
  if (!this->CanIWriteThisFile(outfile)) {
    cmSystemTools::Error("Attempt to write file: ", outfile,
                         " into a source directory.");
    return 0;
  }
  if (!cmSystemTools::FileExists(infile)) {
    cmSystemTools::Error("File ", infile, " does not exist.");
    return 0;
  }
  std::string soutfile = outfile;
  std::string sinfile = infile;
  this->AddCMakeDependFile(sinfile);
  cmSystemTools::ConvertToUnixSlashes(soutfile);

  // Re-generate if non-temporary outputs are missing.
  // when we finalize the configuration we will remove all
  // output files that now don't exist.
  this->AddCMakeOutputFile(soutfile);

  mode_t perm = 0;
  cmSystemTools::GetPermissions(sinfile.c_str(), perm);
  std::string::size_type pos = soutfile.rfind('/');
  if (pos != std::string::npos) {
    std::string path = soutfile.substr(0, pos);
    cmSystemTools::MakeDirectory(path.c_str());
  }

  if (copyonly) {
    if (!cmSystemTools::CopyFileIfDifferent(sinfile.c_str(),
                                            soutfile.c_str())) {
      return 0;
    }
  } else {
    std::string newLineCharacters;
    std::ios::openmode omode = std::ios::out | std::ios::trunc;
    if (newLine.IsValid()) {
      newLineCharacters = newLine.GetCharacters();
      omode |= std::ios::binary;
    } else {
      newLineCharacters = "\n";
    }
    std::string tempOutputFile = soutfile;
    tempOutputFile += ".tmp";
    cmsys::ofstream fout(tempOutputFile.c_str(), omode);
    if (!fout) {
      cmSystemTools::Error("Could not open file for write in copy operation ",
                           tempOutputFile.c_str());
      cmSystemTools::ReportLastSystemError("");
      return 0;
    }
    cmsys::ifstream fin(sinfile.c_str());
    if (!fin) {
      cmSystemTools::Error("Could not open file for read in copy operation ",
                           sinfile.c_str());
      return 0;
    }

    cmsys::FStream::BOM bom = cmsys::FStream::ReadBOM(fin);
    if (bom != cmsys::FStream::BOM_None && bom != cmsys::FStream::BOM_UTF8) {
      std::ostringstream e;
      e << "File starts with a Byte-Order-Mark that is not UTF-8:\n  "
        << sinfile;
      this->IssueMessage(cmake::FATAL_ERROR, e.str());
      return 0;
    }
    // rewind to copy BOM to output file
    fin.seekg(0);

    // now copy input to output and expand variables in the
    // input file at the same time
    std::string inLine;
    std::string outLine;
    while (cmSystemTools::GetLineFromStream(fin, inLine)) {
      outLine.clear();
      this->ConfigureString(inLine, outLine, atOnly, escapeQuotes);
      fout << outLine << newLineCharacters;
    }
    // close the files before attempting to copy
    fin.close();
    fout.close();
    if (!cmSystemTools::CopyFileIfDifferent(tempOutputFile.c_str(),
                                            soutfile.c_str())) {
      res = 0;
    } else {
      cmSystemTools::SetPermissions(soutfile.c_str(), perm);
    }
    cmSystemTools::RemoveFile(tempOutputFile);
  }
  return res;
}

void cmMakefile::SetProperty(const std::string& prop, const char* value)
{
  cmListFileBacktrace lfbt = this->GetBacktrace();
  this->StateSnapshot.GetDirectory().SetProperty(prop, value, lfbt);
}

void cmMakefile::AppendProperty(const std::string& prop, const char* value,
                                bool asString)
{
  cmListFileBacktrace lfbt = this->GetBacktrace();
  this->StateSnapshot.GetDirectory().AppendProperty(prop, value, asString,
                                                    lfbt);
}

const char* cmMakefile::GetProperty(const std::string& prop) const
{
  return this->StateSnapshot.GetDirectory().GetProperty(prop);
}

const char* cmMakefile::GetProperty(const std::string& prop, bool chain) const
{
  return this->StateSnapshot.GetDirectory().GetProperty(prop, chain);
}

bool cmMakefile::GetPropertyAsBool(const std::string& prop) const
{
  return cmSystemTools::IsOn(this->GetProperty(prop));
}

std::vector<std::string> cmMakefile::GetPropertyKeys() const
{
  return this->StateSnapshot.GetDirectory().GetPropertyKeys();
}

cmTarget* cmMakefile::FindLocalNonAliasTarget(const std::string& name) const
{
  cmTargets::iterator i = this->Targets.find(name);
  if (i != this->Targets.end()) {
    return &i->second;
  }
  return nullptr;
}

cmTest* cmMakefile::CreateTest(const std::string& testName)
{
  cmTest* test = this->GetTest(testName);
  if (test) {
    return test;
  }
  test = new cmTest(this);
  test->SetName(testName);
  this->Tests[testName] = test;
  return test;
}

cmTest* cmMakefile::GetTest(const std::string& testName) const
{
  std::map<std::string, cmTest*>::const_iterator mi =
    this->Tests.find(testName);
  if (mi != this->Tests.end()) {
    return mi->second;
  }
  return nullptr;
}

void cmMakefile::GetTests(const std::string& config,
                          std::vector<cmTest*>& tests)
{
  for (auto generator : this->GetTestGenerators()) {
    if (generator->TestsForConfig(config)) {
      tests.push_back(generator->GetTest());
    }
  }
}

void cmMakefile::AddCMakeDependFilesFromUser()
{
  std::vector<std::string> deps;
  if (const char* deps_str = this->GetProperty("CMAKE_CONFIGURE_DEPENDS")) {
    cmSystemTools::ExpandListArgument(deps_str, deps);
  }
  for (std::string const& dep : deps) {
    if (cmSystemTools::FileIsFullPath(dep.c_str())) {
      this->AddCMakeDependFile(dep);
    } else {
      std::string f = this->GetCurrentSourceDirectory();
      f += "/";
      f += dep;
      this->AddCMakeDependFile(f);
    }
  }
}

std::string cmMakefile::FormatListFileStack() const
{
  std::vector<std::string> listFiles;
  cmStateSnapshot snp = this->StateSnapshot;
  while (snp.IsValid()) {
    listFiles.push_back(snp.GetExecutionListFile());
    snp = snp.GetCallStackParent();
  }
  std::reverse(listFiles.begin(), listFiles.end());
  std::ostringstream tmp;
  size_t depth = listFiles.size();
  if (depth > 0) {
    std::vector<std::string>::const_iterator it = listFiles.end();
    do {
      if (depth != listFiles.size()) {
        tmp << "\n                ";
      }
      --it;
      tmp << "[";
      tmp << depth;
      tmp << "]\t";
      tmp << *it;
      depth--;
    } while (it != listFiles.begin());
  }
  return tmp.str();
}

void cmMakefile::PushScope()
{
  this->StateSnapshot =
    this->GetState()->CreateVariableScopeSnapshot(this->StateSnapshot);
  this->PushLoopBlockBarrier();

#if defined(CMAKE_BUILD_WITH_CMAKE)
  this->GetGlobalGenerator()->GetFileLockPool().PushFunctionScope();
#endif
}

void cmMakefile::PopScope()
{
#if defined(CMAKE_BUILD_WITH_CMAKE)
  this->GetGlobalGenerator()->GetFileLockPool().PopFunctionScope();
#endif

  this->PopLoopBlockBarrier();

  this->CheckForUnusedVariables();

  this->PopSnapshot();
}

void cmMakefile::RaiseScope(const std::string& var, const char* varDef)
{
  if (var.empty()) {
    return;
  }

  if (!this->StateSnapshot.RaiseScope(var, varDef)) {
    std::ostringstream m;
    m << "Cannot set \"" << var << "\": current scope has no parent.";
    this->IssueMessage(cmake::AUTHOR_WARNING, m.str());
  }
}

cmTarget* cmMakefile::AddImportedTarget(const std::string& name,
                                        cmStateEnums::TargetType type,
                                        bool global)
{
  // Create the target.
  std::unique_ptr<cmTarget> target(
    new cmTarget(name, type, global ? cmTarget::VisibilityImportedGlobally
                                    : cmTarget::VisibilityImported,
                 this));

  // Add to the set of available imported targets.
  this->ImportedTargets[name] = target.get();
  this->GetGlobalGenerator()->IndexTarget(target.get());

  // Transfer ownership to this cmMakefile object.
  this->ImportedTargetsOwned.push_back(target.get());
  return target.release();
}

cmTarget* cmMakefile::FindTargetToUse(const std::string& name,
                                      bool excludeAliases) const
{
  // Look for an imported target.  These take priority because they
  // are more local in scope and do not have to be globally unique.
  TargetMap::const_iterator imported = this->ImportedTargets.find(name);
  if (imported != this->ImportedTargets.end()) {
    return imported->second;
  }

  // Look for a target built in this directory.
  if (cmTarget* t = this->FindLocalNonAliasTarget(name)) {
    return t;
  }

  // Look for a target built in this project.
  return this->GetGlobalGenerator()->FindTarget(name, excludeAliases);
}

bool cmMakefile::IsAlias(const std::string& name) const
{
  if (this->AliasTargets.find(name) != this->AliasTargets.end()) {
    return true;
  }
  return this->GetGlobalGenerator()->IsAlias(name);
}

bool cmMakefile::EnforceUniqueName(std::string const& name, std::string& msg,
                                   bool isCustom) const
{
  if (this->IsAlias(name)) {
    std::ostringstream e;
    e << "cannot create target \"" << name
      << "\" because an alias with the same name already exists.";
    msg = e.str();
    return false;
  }
  if (cmTarget* existing = this->FindTargetToUse(name)) {
    // The name given conflicts with an existing target.  Produce an
    // error in a compatible way.
    if (existing->IsImported()) {
      // Imported targets were not supported in previous versions.
      // This is new code, so we can make it an error.
      std::ostringstream e;
      e << "cannot create target \"" << name
        << "\" because an imported target with the same name already exists.";
      msg = e.str();
      return false;
    }
    // target names must be globally unique
    switch (this->GetPolicyStatus(cmPolicies::CMP0002)) {
      case cmPolicies::WARN:
        this->IssueMessage(cmake::AUTHOR_WARNING,
                           cmPolicies::GetPolicyWarning(cmPolicies::CMP0002));
        CM_FALLTHROUGH;
      case cmPolicies::OLD:
        return true;
      case cmPolicies::REQUIRED_IF_USED:
      case cmPolicies::REQUIRED_ALWAYS:
        this->IssueMessage(
          cmake::FATAL_ERROR,
          cmPolicies::GetRequiredPolicyError(cmPolicies::CMP0002));
        return true;
      case cmPolicies::NEW:
        break;
    }

    // The conflict is with a non-imported target.
    // Allow this if the user has requested support.
    cmake* cm = this->GetCMakeInstance();
    if (isCustom && existing->GetType() == cmStateEnums::UTILITY &&
        this != existing->GetMakefile() &&
        cm->GetState()->GetGlobalPropertyAsBool(
          "ALLOW_DUPLICATE_CUSTOM_TARGETS")) {
      return true;
    }

    // Produce an error that tells the user how to work around the
    // problem.
    std::ostringstream e;
    e << "cannot create target \"" << name
      << "\" because another target with the same name already exists.  "
      << "The existing target is ";
    switch (existing->GetType()) {
      case cmStateEnums::EXECUTABLE:
        e << "an executable ";
        break;
      case cmStateEnums::STATIC_LIBRARY:
        e << "a static library ";
        break;
      case cmStateEnums::SHARED_LIBRARY:
        e << "a shared library ";
        break;
      case cmStateEnums::MODULE_LIBRARY:
        e << "a module library ";
        break;
      case cmStateEnums::UTILITY:
        e << "a custom target ";
        break;
      case cmStateEnums::INTERFACE_LIBRARY:
        e << "an interface library ";
        break;
      default:
        break;
    }
    e << "created in source directory \""
      << existing->GetMakefile()->GetCurrentSourceDirectory() << "\".  "
      << "See documentation for policy CMP0002 for more details.";
    msg = e.str();
    return false;
  }
  return true;
}

bool cmMakefile::EnforceUniqueDir(const std::string& srcPath,
                                  const std::string& binPath) const
{
  // Make sure the binary directory is unique.
  cmGlobalGenerator* gg = this->GetGlobalGenerator();
  if (gg->BinaryDirectoryIsNew(binPath)) {
    return true;
  }
  std::ostringstream e;
  switch (this->GetPolicyStatus(cmPolicies::CMP0013)) {
    case cmPolicies::WARN:
      // Print the warning.
      /* clang-format off */
      e << cmPolicies::GetPolicyWarning(cmPolicies::CMP0013)
        << "\n"
        << "The binary directory\n"
        << "  " << binPath << "\n"
        << "is already used to build a source directory.  "
        << "This command uses it to build source directory\n"
        << "  " << srcPath << "\n"
        << "which can generate conflicting build files.  "
        << "CMake does not support this use case but it used "
        << "to work accidentally and is being allowed for "
        << "compatibility.";
      /* clang-format on */
      this->IssueMessage(cmake::AUTHOR_WARNING, e.str());
      CM_FALLTHROUGH;
    case cmPolicies::OLD:
      // OLD behavior does not warn.
      return true;
    case cmPolicies::REQUIRED_IF_USED:
    case cmPolicies::REQUIRED_ALWAYS:
      e << cmPolicies::GetRequiredPolicyError(cmPolicies::CMP0013) << "\n";
      CM_FALLTHROUGH;
    case cmPolicies::NEW:
      // NEW behavior prints the error.
      /* clang-format off */
      e << "The binary directory\n"
        << "  " << binPath << "\n"
        << "is already used to build a source directory.  "
        << "It cannot be used to build source directory\n"
        << "  " << srcPath << "\n"
        << "Specify a unique binary directory name.";
      /* clang-format on */
      this->IssueMessage(cmake::FATAL_ERROR, e.str());
      break;
  }

  return false;
}

static std::string const matchVariables[] = {
  "CMAKE_MATCH_0", "CMAKE_MATCH_1", "CMAKE_MATCH_2", "CMAKE_MATCH_3",
  "CMAKE_MATCH_4", "CMAKE_MATCH_5", "CMAKE_MATCH_6", "CMAKE_MATCH_7",
  "CMAKE_MATCH_8", "CMAKE_MATCH_9"
};

static std::string const nMatchesVariable = "CMAKE_MATCH_COUNT";

void cmMakefile::ClearMatches()
{
  const char* nMatchesStr = this->GetDefinition(nMatchesVariable);
  if (!nMatchesStr) {
    return;
  }
  int nMatches = atoi(nMatchesStr);
  for (int i = 0; i <= nMatches; i++) {
    std::string const& var = matchVariables[i];
    std::string const& s = this->GetSafeDefinition(var);
    if (!s.empty()) {
      this->AddDefinition(var, "");
      this->MarkVariableAsUsed(var);
    }
  }
  this->AddDefinition(nMatchesVariable, "0");
  this->MarkVariableAsUsed(nMatchesVariable);
}

void cmMakefile::StoreMatches(cmsys::RegularExpression& re)
{
  char highest = 0;
  for (int i = 0; i < 10; i++) {
    std::string const& m = re.match(i);
    if (!m.empty()) {
      std::string const& var = matchVariables[i];
      this->AddDefinition(var, m.c_str());
      this->MarkVariableAsUsed(var);
      highest = static_cast<char>('0' + i);
    }
  }
  char nMatches[] = { highest, '\0' };
  this->AddDefinition(nMatchesVariable, nMatches);
  this->MarkVariableAsUsed(nMatchesVariable);
}

cmStateSnapshot cmMakefile::GetStateSnapshot() const
{
  return this->StateSnapshot;
}

const char* cmMakefile::GetDefineFlagsCMP0059() const
{
  return this->DefineFlagsOrig.c_str();
}

cmPolicies::PolicyStatus cmMakefile::GetPolicyStatus(
  cmPolicies::PolicyID id) const
{
  return this->StateSnapshot.GetPolicy(id);
}

bool cmMakefile::PolicyOptionalWarningEnabled(std::string const& var)
{
  // Check for an explicit CMAKE_POLICY_WARNING_CMP<NNNN> setting.
  if (const char* val = this->GetDefinition(var)) {
    return cmSystemTools::IsOn(val);
  }
  // Enable optional policy warnings with --debug-output, --trace,
  // or --trace-expand.
  cmake* cm = this->GetCMakeInstance();
  return cm->GetDebugOutput() || cm->GetTrace();
}

bool cmMakefile::SetPolicy(const char* id, cmPolicies::PolicyStatus status)
{
  cmPolicies::PolicyID pid;
  if (!cmPolicies::GetPolicyID(id, /* out */ pid)) {
    std::ostringstream e;
    e << "Policy \"" << id << "\" is not known to this version of CMake.";
    this->IssueMessage(cmake::FATAL_ERROR, e.str());
    return false;
  }
  return this->SetPolicy(pid, status);
}

bool cmMakefile::SetPolicy(cmPolicies::PolicyID id,
                           cmPolicies::PolicyStatus status)
{
  // A REQUIRED_ALWAYS policy may be set only to NEW.
  if (status != cmPolicies::NEW &&
      cmPolicies::GetPolicyStatus(id) == cmPolicies::REQUIRED_ALWAYS) {
    std::string msg = cmPolicies::GetRequiredAlwaysPolicyError(id);
    this->IssueMessage(cmake::FATAL_ERROR, msg);
    return false;
  }

  // Deprecate old policies, especially those that require a lot
  // of code to maintain the old behavior.
  if (status == cmPolicies::OLD && id <= cmPolicies::CMP0054) {
    this->IssueMessage(cmake::DEPRECATION_WARNING,
                       cmPolicies::GetPolicyDeprecatedWarning(id));
  }

  this->StateSnapshot.SetPolicy(id, status);
  return true;
}

cmMakefile::PolicyPushPop::PolicyPushPop(cmMakefile* m)
  : Makefile(m)
{
  this->Makefile->PushPolicy();
}

cmMakefile::PolicyPushPop::~PolicyPushPop()
{
  this->Makefile->PopPolicy();
}

void cmMakefile::PushPolicy(bool weak, cmPolicies::PolicyMap const& pm)
{
  this->StateSnapshot.PushPolicy(pm, weak);
}

void cmMakefile::PopPolicy()
{
  if (!this->StateSnapshot.PopPolicy()) {
    this->IssueMessage(cmake::FATAL_ERROR,
                       "cmake_policy POP without matching PUSH");
  }
}

void cmMakefile::PopSnapshot(bool reportError)
{
  // cmStateSnapshot manages nested policy scopes within it.
  // Since the scope corresponding to the snapshot is closing,
  // reject any still-open nested policy scopes with an error.
  while (!this->StateSnapshot.CanPopPolicyScope()) {
    if (reportError) {
      this->IssueMessage(cmake::FATAL_ERROR,
                         "cmake_policy PUSH without matching POP");
      reportError = false;
    }
    this->PopPolicy();
  }

  this->StateSnapshot = this->GetState()->Pop(this->StateSnapshot);
  assert(this->StateSnapshot.IsValid());
}

bool cmMakefile::SetPolicyVersion(const char* version)
{
  return cmPolicies::ApplyPolicyVersion(this, version);
}

bool cmMakefile::HasCMP0054AlreadyBeenReported(
  cmListFileContext const& context) const
{
  return !this->CMP0054ReportedIds.insert(context).second;
}

void cmMakefile::RecordPolicies(cmPolicies::PolicyMap& pm)
{
  /* Record the setting of every policy.  */
  typedef cmPolicies::PolicyID PolicyID;
  for (PolicyID pid = cmPolicies::CMP0000; pid != cmPolicies::CMPCOUNT;
       pid = PolicyID(pid + 1)) {
    pm.Set(pid, this->GetPolicyStatus(pid));
  }
}

bool cmMakefile::IgnoreErrorsCMP0061() const
{
  bool ignoreErrors = true;
  switch (this->GetPolicyStatus(cmPolicies::CMP0061)) {
    case cmPolicies::WARN:
    // No warning for this policy!
    case cmPolicies::OLD:
      break;
    case cmPolicies::REQUIRED_IF_USED:
    case cmPolicies::REQUIRED_ALWAYS:
    case cmPolicies::NEW:
      ignoreErrors = false;
      break;
  }
  return ignoreErrors;
}

#define FEATURE_STRING(F) , #F
static const char* const C_FEATURES[] = { nullptr FOR_EACH_C_FEATURE(
  FEATURE_STRING) };

static const char* const CXX_FEATURES[] = { nullptr FOR_EACH_CXX_FEATURE(
  FEATURE_STRING) };
#undef FEATURE_STRING

static const char* const C_STANDARDS[] = { "90", "99", "11" };
static const char* const CXX_STANDARDS[] = { "98", "11", "14", "17" };

bool cmMakefile::AddRequiredTargetFeature(cmTarget* target,
                                          const std::string& feature,
                                          std::string* error) const
{
  if (cmGeneratorExpression::Find(feature) != std::string::npos) {
    target->AppendProperty("COMPILE_FEATURES", feature.c_str());
    return true;
  }

  std::string lang;
  if (!this->CompileFeatureKnown(target, feature, lang, error)) {
    return false;
  }

  const char* features = this->CompileFeaturesAvailable(lang, error);
  if (!features) {
    return false;
  }

  std::vector<std::string> availableFeatures;
  cmSystemTools::ExpandListArgument(features, availableFeatures);
  if (std::find(availableFeatures.begin(), availableFeatures.end(), feature) ==
      availableFeatures.end()) {
    std::ostringstream e;
    e << "The compiler feature \"" << feature << "\" is not known to " << lang
      << " compiler\n\""
      << this->GetDefinition("CMAKE_" + lang + "_COMPILER_ID")
      << "\"\nversion "
      << this->GetDefinition("CMAKE_" + lang + "_COMPILER_VERSION") << ".";
    if (error) {
      *error = e.str();
    } else {
      this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                             this->Backtrace);
    }
    return false;
  }

  target->AppendProperty("COMPILE_FEATURES", feature.c_str());

  return lang == "C"
    ? this->AddRequiredTargetCFeature(target, feature, error)
    : this->AddRequiredTargetCxxFeature(target, feature, error);
}

bool cmMakefile::CompileFeatureKnown(cmTarget const* target,
                                     const std::string& feature,
                                     std::string& lang,
                                     std::string* error) const
{
  assert(cmGeneratorExpression::Find(feature) == std::string::npos);

  bool isCFeature =
    std::find_if(cm::cbegin(C_FEATURES) + 1, cm::cend(C_FEATURES),
                 cmStrCmp(feature)) != cm::cend(C_FEATURES);
  if (isCFeature) {
    lang = "C";
    return true;
  }
  bool isCxxFeature =
    std::find_if(cm::cbegin(CXX_FEATURES) + 1, cm::cend(CXX_FEATURES),
                 cmStrCmp(feature)) != cm::cend(CXX_FEATURES);
  if (isCxxFeature) {
    lang = "CXX";
    return true;
  }
  std::ostringstream e;
  if (error) {
    e << "specified";
  } else {
    e << "Specified";
  }
  e << " unknown feature \"" << feature << "\" for "
                                           "target \""
    << target->GetName() << "\".";
  if (error) {
    *error = e.str();
  } else {
    this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                           this->Backtrace);
  }
  return false;
}

const char* cmMakefile::CompileFeaturesAvailable(const std::string& lang,
                                                 std::string* error) const
{
  if (!this->GlobalGenerator->GetLanguageEnabled(lang)) {
    std::ostringstream e;
    if (error) {
      e << "cannot";
    } else {
      e << "Cannot";
    }
    e << " use features from non-enabled language " << lang;
    if (error) {
      *error = e.str();
    } else {
      this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                             this->Backtrace);
    }
    return nullptr;
  }

  const char* featuresKnown =
    this->GetDefinition("CMAKE_" + lang + "_COMPILE_FEATURES");

  if (!featuresKnown || !*featuresKnown) {
    std::ostringstream e;
    if (error) {
      e << "no";
    } else {
      e << "No";
    }
    e << " known features for " << lang << " compiler\n\""
      << this->GetSafeDefinition("CMAKE_" + lang + "_COMPILER_ID")
      << "\"\nversion "
      << this->GetSafeDefinition("CMAKE_" + lang + "_COMPILER_VERSION") << ".";
    if (error) {
      *error = e.str();
    } else {
      this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                             this->Backtrace);
    }
    return nullptr;
  }
  return featuresKnown;
}

bool cmMakefile::HaveStandardAvailable(cmTarget const* target,
                                       std::string const& lang,
                                       const std::string& feature) const
{
  return lang == "C" ? this->HaveCStandardAvailable(target, feature)
                     : this->HaveCxxStandardAvailable(target, feature);
}

bool cmMakefile::HaveCStandardAvailable(cmTarget const* target,
                                        const std::string& feature) const
{
  const char* defaultCStandard =
    this->GetDefinition("CMAKE_C_STANDARD_DEFAULT");
  if (!defaultCStandard) {
    std::ostringstream e;
    e << "CMAKE_C_STANDARD_DEFAULT is not set.  COMPILE_FEATURES support "
         "not fully configured for this compiler.";
    this->IssueMessage(cmake::INTERNAL_ERROR, e.str());
    // Return true so the caller does not try to lookup the default standard.
    return true;
  }
  if (std::find_if(cm::cbegin(C_STANDARDS), cm::cend(C_STANDARDS),
                   cmStrCmp(defaultCStandard)) == cm::cend(C_STANDARDS)) {
    std::ostringstream e;
    e << "The CMAKE_C_STANDARD_DEFAULT variable contains an "
         "invalid value: \""
      << defaultCStandard << "\".";
    this->IssueMessage(cmake::INTERNAL_ERROR, e.str());
    return false;
  }

  bool needC90 = false;
  bool needC99 = false;
  bool needC11 = false;

  this->CheckNeededCLanguage(feature, needC90, needC99, needC11);

  const char* existingCStandard = target->GetProperty("C_STANDARD");
  if (!existingCStandard) {
    existingCStandard = defaultCStandard;
  }

  if (std::find_if(cm::cbegin(C_STANDARDS), cm::cend(C_STANDARDS),
                   cmStrCmp(existingCStandard)) == cm::cend(C_STANDARDS)) {
    std::ostringstream e;
    e << "The C_STANDARD property on target \"" << target->GetName()
      << "\" contained an invalid value: \"" << existingCStandard << "\".";
    this->IssueMessage(cmake::FATAL_ERROR, e.str());
    return false;
  }

  const char* const* existingCIt = existingCStandard
    ? std::find_if(cm::cbegin(C_STANDARDS), cm::cend(C_STANDARDS),
                   cmStrCmp(existingCStandard))
    : cm::cend(C_STANDARDS);

  if (needC11 && existingCStandard &&
      existingCIt < std::find_if(cm::cbegin(C_STANDARDS),
                                 cm::cend(C_STANDARDS), cmStrCmp("11"))) {
    return false;
  }
  if (needC99 && existingCStandard &&
      existingCIt < std::find_if(cm::cbegin(C_STANDARDS),
                                 cm::cend(C_STANDARDS), cmStrCmp("99"))) {
    return false;
  }
  if (needC90 && existingCStandard &&
      existingCIt < std::find_if(cm::cbegin(C_STANDARDS),
                                 cm::cend(C_STANDARDS), cmStrCmp("90"))) {
    return false;
  }
  return true;
}

bool cmMakefile::IsLaterStandard(std::string const& lang,
                                 std::string const& lhs,
                                 std::string const& rhs)
{
  if (lang == "C") {
    const char* const* rhsIt = std::find_if(
      cm::cbegin(C_STANDARDS), cm::cend(C_STANDARDS), cmStrCmp(rhs));

    return std::find_if(rhsIt, cm::cend(C_STANDARDS), cmStrCmp(lhs)) !=
      cm::cend(C_STANDARDS);
  }
  const char* const* rhsIt = std::find_if(
    cm::cbegin(CXX_STANDARDS), cm::cend(CXX_STANDARDS), cmStrCmp(rhs));

  return std::find_if(rhsIt, cm::cend(CXX_STANDARDS), cmStrCmp(lhs)) !=
    cm::cend(CXX_STANDARDS);
}

bool cmMakefile::HaveCxxStandardAvailable(cmTarget const* target,
                                          const std::string& feature) const
{
  const char* defaultCxxStandard =
    this->GetDefinition("CMAKE_CXX_STANDARD_DEFAULT");
  if (!defaultCxxStandard) {
    std::ostringstream e;
    e << "CMAKE_CXX_STANDARD_DEFAULT is not set.  COMPILE_FEATURES support "
         "not fully configured for this compiler.";
    this->IssueMessage(cmake::INTERNAL_ERROR, e.str());
    // Return true so the caller does not try to lookup the default standard.
    return true;
  }
  if (std::find_if(cm::cbegin(CXX_STANDARDS), cm::cend(CXX_STANDARDS),
                   cmStrCmp(defaultCxxStandard)) == cm::cend(CXX_STANDARDS)) {
    std::ostringstream e;
    e << "The CMAKE_CXX_STANDARD_DEFAULT variable contains an "
         "invalid value: \""
      << defaultCxxStandard << "\".";
    this->IssueMessage(cmake::INTERNAL_ERROR, e.str());
    return false;
  }

  bool needCxx98 = false;
  bool needCxx11 = false;
  bool needCxx14 = false;
  bool needCxx17 = false;
  this->CheckNeededCxxLanguage(feature, needCxx98, needCxx11, needCxx14,
                               needCxx17);

  const char* existingCxxStandard = target->GetProperty("CXX_STANDARD");
  if (!existingCxxStandard) {
    existingCxxStandard = defaultCxxStandard;
  }

  const char* const* existingCxxLevel =
    std::find_if(cm::cbegin(CXX_STANDARDS), cm::cend(CXX_STANDARDS),
                 cmStrCmp(existingCxxStandard));
  if (existingCxxLevel == cm::cend(CXX_STANDARDS)) {
    std::ostringstream e;
    e << "The CXX_STANDARD property on target \"" << target->GetName()
      << "\" contained an invalid value: \"" << existingCxxStandard << "\".";
    this->IssueMessage(cmake::FATAL_ERROR, e.str());
    return false;
  }

  /* clang-format off */
  const char* const* needCxxLevel =
    needCxx17 ? &CXX_STANDARDS[3]
    : needCxx14 ? &CXX_STANDARDS[2]
    : needCxx11 ? &CXX_STANDARDS[1]
    : needCxx98 ? &CXX_STANDARDS[0]
    : nullptr;
  /* clang-format on */

  return !needCxxLevel || needCxxLevel <= existingCxxLevel;
}

void cmMakefile::CheckNeededCxxLanguage(const std::string& feature,
                                        bool& needCxx98, bool& needCxx11,
                                        bool& needCxx14, bool& needCxx17) const
{
  if (const char* propCxx98 =
        this->GetDefinition("CMAKE_CXX98_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propCxx98, props);
    needCxx98 = std::find(props.begin(), props.end(), feature) != props.end();
  }
  if (const char* propCxx11 =
        this->GetDefinition("CMAKE_CXX11_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propCxx11, props);
    needCxx11 = std::find(props.begin(), props.end(), feature) != props.end();
  }
  if (const char* propCxx14 =
        this->GetDefinition("CMAKE_CXX14_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propCxx14, props);
    needCxx14 = std::find(props.begin(), props.end(), feature) != props.end();
  }
  if (const char* propCxx17 =
        this->GetDefinition("CMAKE_CXX17_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propCxx17, props);
    needCxx17 = std::find(props.begin(), props.end(), feature) != props.end();
  }
}

bool cmMakefile::AddRequiredTargetCxxFeature(cmTarget* target,
                                             const std::string& feature,
                                             std::string* error) const
{
  bool needCxx98 = false;
  bool needCxx11 = false;
  bool needCxx14 = false;
  bool needCxx17 = false;

  this->CheckNeededCxxLanguage(feature, needCxx98, needCxx11, needCxx14,
                               needCxx17);

  const char* existingCxxStandard = target->GetProperty("CXX_STANDARD");
  const char* const* existingCxxLevel = nullptr;
  if (existingCxxStandard) {
    existingCxxLevel =
      std::find_if(cm::cbegin(CXX_STANDARDS), cm::cend(CXX_STANDARDS),
                   cmStrCmp(existingCxxStandard));
    if (existingCxxLevel == cm::cend(CXX_STANDARDS)) {
      std::ostringstream e;
      e << "The CXX_STANDARD property on target \"" << target->GetName()
        << "\" contained an invalid value: \"" << existingCxxStandard << "\".";
      if (error) {
        *error = e.str();
      } else {
        this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                               this->Backtrace);
      }
      return false;
    }
  }

  const char* existingCudaStandard = target->GetProperty("CUDA_STANDARD");
  const char* const* existingCudaLevel = nullptr;
  if (existingCudaStandard) {
    existingCudaLevel =
      std::find_if(cm::cbegin(CXX_STANDARDS), cm::cend(CXX_STANDARDS),
                   cmStrCmp(existingCudaStandard));
    if (existingCudaLevel == cm::cend(CXX_STANDARDS)) {
      std::ostringstream e;
      e << "The CUDA_STANDARD property on target \"" << target->GetName()
        << "\" contained an invalid value: \"" << existingCudaStandard
        << "\".";
      if (error) {
        *error = e.str();
      } else {
        this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                               this->Backtrace);
      }
      return false;
    }
  }

  /* clang-format off */
  const char* const* needCxxLevel =
    needCxx17 ? &CXX_STANDARDS[3]
    : needCxx14 ? &CXX_STANDARDS[2]
    : needCxx11 ? &CXX_STANDARDS[1]
    : needCxx98 ? &CXX_STANDARDS[0]
    : nullptr;
  /* clang-format on */

  if (needCxxLevel) {
    // Ensure the C++ language level is high enough to support
    // the needed C++ features.
    if (!existingCxxLevel || existingCxxLevel < needCxxLevel) {
      target->SetProperty("CXX_STANDARD", *needCxxLevel);
    }

    // Ensure the CUDA language level is high enough to support
    // the needed C++ features.
    if (!existingCudaLevel || existingCudaLevel < needCxxLevel) {
      target->SetProperty("CUDA_STANDARD", *needCxxLevel);
    }
  }

  return true;
}

void cmMakefile::CheckNeededCLanguage(const std::string& feature,
                                      bool& needC90, bool& needC99,
                                      bool& needC11) const
{
  if (const char* propC90 =
        this->GetDefinition("CMAKE_C90_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propC90, props);
    needC90 = std::find(props.begin(), props.end(), feature) != props.end();
  }
  if (const char* propC99 =
        this->GetDefinition("CMAKE_C99_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propC99, props);
    needC99 = std::find(props.begin(), props.end(), feature) != props.end();
  }
  if (const char* propC11 =
        this->GetDefinition("CMAKE_C11_COMPILE_FEATURES")) {
    std::vector<std::string> props;
    cmSystemTools::ExpandListArgument(propC11, props);
    needC11 = std::find(props.begin(), props.end(), feature) != props.end();
  }
}

bool cmMakefile::AddRequiredTargetCFeature(cmTarget* target,
                                           const std::string& feature,
                                           std::string* error) const
{
  bool needC90 = false;
  bool needC99 = false;
  bool needC11 = false;

  this->CheckNeededCLanguage(feature, needC90, needC99, needC11);

  const char* existingCStandard = target->GetProperty("C_STANDARD");
  if (existingCStandard) {
    if (std::find_if(cm::cbegin(C_STANDARDS), cm::cend(C_STANDARDS),
                     cmStrCmp(existingCStandard)) == cm::cend(C_STANDARDS)) {
      std::ostringstream e;
      e << "The C_STANDARD property on target \"" << target->GetName()
        << "\" contained an invalid value: \"" << existingCStandard << "\".";
      if (error) {
        *error = e.str();
      } else {
        this->GetCMakeInstance()->IssueMessage(cmake::FATAL_ERROR, e.str(),
                                               this->Backtrace);
      }
      return false;
    }
  }
  const char* const* existingCIt = existingCStandard
    ? std::find_if(cm::cbegin(C_STANDARDS), cm::cend(C_STANDARDS),
                   cmStrCmp(existingCStandard))
    : cm::cend(C_STANDARDS);

  bool setC90 = needC90 && !existingCStandard;
  bool setC99 = needC99 && !existingCStandard;
  bool setC11 = needC11 && !existingCStandard;

  if (needC11 && existingCStandard &&
      existingCIt < std::find_if(cm::cbegin(C_STANDARDS),
                                 cm::cend(C_STANDARDS), cmStrCmp("11"))) {
    setC11 = true;
  } else if (needC99 && existingCStandard &&
             existingCIt < std::find_if(cm::cbegin(C_STANDARDS),
                                        cm::cend(C_STANDARDS),
                                        cmStrCmp("99"))) {
    setC99 = true;
  } else if (needC90 && existingCStandard &&
             existingCIt < std::find_if(cm::cbegin(C_STANDARDS),
                                        cm::cend(C_STANDARDS),
                                        cmStrCmp("90"))) {
    setC90 = true;
  }

  if (setC11) {
    target->SetProperty("C_STANDARD", "11");
  } else if (setC99) {
    target->SetProperty("C_STANDARD", "99");
  } else if (setC90) {
    target->SetProperty("C_STANDARD", "90");
  }
  return true;
}

cmMakefile::FunctionPushPop::FunctionPushPop(cmMakefile* mf,
                                             const std::string& fileName,
                                             cmPolicies::PolicyMap const& pm)
  : Makefile(mf)
  , ReportError(true)
{
  this->Makefile->PushFunctionScope(fileName, pm);
}

cmMakefile::FunctionPushPop::~FunctionPushPop()
{
  this->Makefile->PopFunctionScope(this->ReportError);
}

cmMakefile::MacroPushPop::MacroPushPop(cmMakefile* mf,
                                       const std::string& fileName,
                                       const cmPolicies::PolicyMap& pm)
  : Makefile(mf)
  , ReportError(true)
{
  this->Makefile->PushMacroScope(fileName, pm);
}

cmMakefile::MacroPushPop::~MacroPushPop()
{
  this->Makefile->PopMacroScope(this->ReportError);
}