/// \brief Helper to add the three variant paths for a libstdc++ installation.

/*static*/ bool FreeBSD::addLibStdCXXIncludePaths(Twine Base, Twine TargetArchDir,

                                                const ArgList &DriverArgs,

                                                ArgStringList &CC1Args) {

  if (!llvm::sys::fs::exists(Base))

    return false;

  addSystemInclude(DriverArgs, CC1Args, Base);

  addSystemInclude(DriverArgs, CC1Args, Base + "/" + TargetArchDir);

  addSystemInclude(DriverArgs, CC1Args, Base + "/backward");

  return true;

}

/// \brief Helper to add an extra variant path for an (Ubuntu) multilib

/// libstdc++ installation.

/*static*/ bool FreeBSD::addLibStdCXXIncludePaths(Twine Base, Twine Suffix,

                                                Twine TargetArchDir,

                                                Twine MultiLibSuffix,

                                                const ArgList &DriverArgs,

                                                ArgStringList &CC1Args) {

  if (!addLibStdCXXIncludePaths(Base+Suffix, TargetArchDir + MultiLibSuffix,

                                DriverArgs, CC1Args))

    return false;

  addSystemInclude(DriverArgs, CC1Args, Base + "/" + TargetArchDir + Suffix

                   + MultiLibSuffix);

  return true;

}

void FreeBSD::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,

                                         ArgStringList &CC1Args) const {

  if (DriverArgs.hasArg(options::OPT_nostdlibinc) ||

      DriverArgs.hasArg(options::OPT_nostdincxx))

    return;

  // Check if libc++ has been enabled and provide its include paths if so.

  if (GetCXXStdlibType(DriverArgs) == ToolChain::CST_Libcxx) {

    // libc++ is always installed at a fixed path on Linux currently.

    addSystemInclude(DriverArgs, CC1Args,

                     getDriver().SysRoot + "/usr/include/c++/v1");

    return;

  }

  // We need a detected GCC installation on Linux to provide libstdc++'s

  // headers. We handled the libc++ case above.

  if (!GCCInstallation.isValid())

    return;

  // By default, look for the C++ headers in an include directory adjacent to

  // the lib directory of the GCC installation. Note that this is expect to be

  // equivalent to '/usr/include/c++/X.Y' in almost all cases.

  StringRef LibDir = GCCInstallation.getParentLibPath();

  StringRef InstallDir = GCCInstallation.getInstallPath();

  StringRef Version = GCCInstallation.getVersion().Text;

  StringRef TripleStr = GCCInstallation.getTriple().str();

  if (addLibStdCXXIncludePaths(LibDir.str() + "/../include",

                               "/c++/" + Version.str(),

                               TripleStr,

                               GCCInstallation.getMultiarchSuffix(),

                               DriverArgs, CC1Args))

    return;

  const std::string IncludePathCandidates[] = {

    // Gentoo is weird and places its headers inside the GCC install, so if the

    // first attempt to find the headers fails, try this pattern.

    InstallDir.str() + "/include/g++-v4",

    // Android standalone toolchain has C++ headers in yet another place.

    LibDir.str() + "/../" + TripleStr.str() + "/include/c++/" + Version.str(),

    // Freescale SDK C++ headers are directly in <sysroot>/usr/include/c++,

    // without a subdirectory corresponding to the gcc version.

    LibDir.str() + "/../include/c++",

  };

  for (unsigned i = 0; i < llvm::array_lengthof(IncludePathCandidates); ++i) {

    if (addLibStdCXXIncludePaths(IncludePathCandidates[i], (TripleStr +

                GCCInstallation.getMultiarchSuffix()),

            DriverArgs, CC1Args))

      break;

  }

}

  virtual void AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,

                                            ArgStringList &CC1Args) const;

private:

  static bool addLibStdCXXIncludePaths(Twine Base, Twine Suffix,

                                       Twine TargetArchDir,

                                       Twine MultiLibSuffix,

                                       const ArgList &DriverArgs,

                                       ArgStringList &CC1Args);

  static bool addLibStdCXXIncludePaths(Twine Base, Twine TargetArchDir,

                                       const ArgList &DriverArgs,

                                       ArgStringList &CC1Args);