code in context

bool Generic_GCC::addGCCLibStdCxxIncludePaths(
    const llvm::opt::ArgList &DriverArgs, llvm::opt::ArgStringList &CC1Args,
    StringRef DebianMultiarch) const {
  assert(GCCInstallation.isValid());

  // 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 TripleStr = GCCInstallation.getTriple().str();
  const Multilib &Multilib = GCCInstallation.getMultilib();
  const GCCVersion &Version = GCCInstallation.getVersion();

  // Try /../$triple/include/c++/$version then /../include/c++/$version.
  if (addLibStdCXXIncludePaths(
          LibDir.str() + "/../" + TripleStr + "/include/c++/" + Version.Text,
          TripleStr, Multilib.includeSuffix(), DriverArgs, CC1Args))
    return true;
  // Detect Debian g++-multiarch-incdir.diff.
  StringRef DebianMultiarch =
      GCCInstallation.getTriple().getArch() == llvm::Triple::x86
          ? "i386-linux-gnu"
          : TripleStr;
  if (addLibStdCXXIncludePaths(LibDir.str() + "/../include/c++/" + Version.Text,
                               DebianMultiarch, Multilib.includeSuffix(),
                               DriverArgs, CC1Args, /*Debian=*/true))
    return true;

  if (addLibStdCXXIncludePaths(LibDir.str() + "/../include/c++/" + Version.Text,
                               TripleStr, Multilib.includeSuffix(),
                               DriverArgs, CC1Args, /*Debian=*/true))
    return true;

  // Otherwise, fall back on a bunch of options which don't use multiarch
  // layouts for simplicity.