1 files changed, 168 insertions, 0 deletions
diff --git a/clang/lib/Driver/ToolChains/Hurd.cpp b/clang/lib/Driver/ToolChains/Hurd.cpp
new file mode 100644
index 000000000000..92b0a7f2483f
--- /dev/null
+++ b/clang/lib/Driver/ToolChains/Hurd.cpp
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+//===--- Hurd.cpp - Hurd ToolChain Implementations --------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "Hurd.h"
+#include "CommonArgs.h"
+#include "clang/Config/config.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/Options.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/VirtualFileSystem.h"
+
+using namespace clang::driver;
+using namespace clang::driver::toolchains;
+using namespace clang;
+using namespace llvm::opt;
+
+using tools::addPathIfExists;
+
+/// Get our best guess at the multiarch triple for a target.
+///
+/// Debian-based systems are starting to use a multiarch setup where they use
+/// a target-triple directory in the library and header search paths.
+/// Unfortunately, this triple does not align with the vanilla target triple,
+/// so we provide a rough mapping here.
+static std::string getMultiarchTriple(const Driver &D,
+                                      const llvm::Triple &TargetTriple,
+                                      StringRef SysRoot) {
+  if (TargetTriple.getArch() == llvm::Triple::x86) {
+    // We use the existence of '/lib/<triple>' as a directory to detect some
+    // common hurd triples that don't quite match the Clang triple for both
+    // 32-bit and 64-bit targets. Multiarch fixes its install triples to these
+    // regardless of what the actual target triple is.
+    if (D.getVFS().exists(SysRoot + "/lib/i386-gnu"))
+      return "i386-gnu";
+  }
+
+  // For most architectures, just use whatever we have rather than trying to be
+  // clever.
+  return TargetTriple.str();
+}
+
+static StringRef getOSLibDir(const llvm::Triple &Triple, const ArgList &Args) {
+  // It happens that only x86 and PPC use the 'lib32' variant of oslibdir, and
+  // using that variant while targeting other architectures causes problems
+  // because the libraries are laid out in shared system roots that can't cope
+  // with a 'lib32' library search path being considered. So we only enable
+  // them when we know we may need it.
+  //
+  // FIXME: This is a bit of a hack. We should really unify this code for
+  // reasoning about oslibdir spellings with the lib dir spellings in the
+  // GCCInstallationDetector, but that is a more significant refactoring.
+
+  if (Triple.getArch() == llvm::Triple::x86)
+    return "lib32";
+
+  return Triple.isArch32Bit() ? "lib" : "lib64";
+}
+
+Hurd::Hurd(const Driver &D, const llvm::Triple &Triple,
+           const ArgList &Args)
+    : Generic_ELF(D, Triple, Args) {
+  std::string SysRoot = computeSysRoot();
+  path_list &Paths = getFilePaths();
+
+  const std::string OSLibDir = getOSLibDir(Triple, Args);
+  const std::string MultiarchTriple = getMultiarchTriple(D, Triple, SysRoot);
+
+  // If we are currently running Clang inside of the requested system root, add
+  // its parent library paths to those searched.
+  // FIXME: It's not clear whether we should use the driver's installed
+  // directory ('Dir' below) or the ResourceDir.
+  if (StringRef(D.Dir).startswith(SysRoot)) {
+    addPathIfExists(D, D.Dir + "/../lib/" + MultiarchTriple, Paths);
+    addPathIfExists(D, D.Dir + "/../" + OSLibDir, Paths);
+  }
+
+  addPathIfExists(D, SysRoot + "/lib/" + MultiarchTriple, Paths);
+  addPathIfExists(D, SysRoot + "/lib/../" + OSLibDir, Paths);
+
+  addPathIfExists(D, SysRoot + "/usr/lib/" + MultiarchTriple, Paths);
+  addPathIfExists(D, SysRoot + "/usr/lib/../" + OSLibDir, Paths);
+
+  // If we are currently running Clang inside of the requested system root, add
+  // its parent library path to those searched.
+  // FIXME: It's not clear whether we should use the driver's installed
+  // directory ('Dir' below) or the ResourceDir.
+  if (StringRef(D.Dir).startswith(SysRoot))
+    addPathIfExists(D, D.Dir + "/../lib", Paths);
+
+  addPathIfExists(D, SysRoot + "/lib", Paths);
+  addPathIfExists(D, SysRoot + "/usr/lib", Paths);
+}
+
+bool Hurd::HasNativeLLVMSupport() const { return true; }
+
+Tool *Hurd::buildLinker() const { return new tools::gnutools::Linker(*this); }
+
+Tool *Hurd::buildAssembler() const {
+  return new tools::gnutools::Assembler(*this);
+}
+
+std::string Hurd::computeSysRoot() const {
+  if (!getDriver().SysRoot.empty())
+    return getDriver().SysRoot;
+
+  return std::string();
+}
+
+std::string Hurd::getDynamicLinker(const ArgList &Args) const {
+  if (getArch() == llvm::Triple::x86)
+    return "/lib/ld.so";
+
+  llvm_unreachable("unsupported architecture");
+}
+
+void Hurd::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
+                                     ArgStringList &CC1Args) const {
+  const Driver &D = getDriver();
+  std::string SysRoot = computeSysRoot();
+
+  if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
+    return;
+
+  if (!DriverArgs.hasArg(options::OPT_nostdlibinc))
+    addSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/local/include");
+
+  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
+    SmallString<128> P(D.ResourceDir);
+    llvm::sys::path::append(P, "include");
+    addSystemInclude(DriverArgs, CC1Args, P);
+  }
+
+  if (DriverArgs.hasArg(options::OPT_nostdlibinc))
+    return;
+
+  // Check for configure-time C include directories.
+  StringRef CIncludeDirs(C_INCLUDE_DIRS);
+  if (CIncludeDirs != "") {
+    SmallVector<StringRef, 5> Dirs;
+    CIncludeDirs.split(Dirs, ":");
+    for (StringRef Dir : Dirs) {
+      StringRef Prefix =
+          llvm::sys::path::is_absolute(Dir) ? StringRef(SysRoot) : "";
+      addExternCSystemInclude(DriverArgs, CC1Args, Prefix + Dir);
+    }
+    return;
+  }
+
+  // Lacking those, try to detect the correct set of system includes for the
+  // target triple.
+  if (getTriple().getArch() == llvm::Triple::x86) {
+    std::string Path = SysRoot + "/usr/include/i386-gnu";
+    if (D.getVFS().exists(Path))
+      addExternCSystemInclude(DriverArgs, CC1Args, Path);
+  }
+
+  // Add an include of '/include' directly. This isn't provided by default by
+  // system GCCs, but is often used with cross-compiling GCCs, and harmless to
+  // add even when Clang is acting as-if it were a system compiler.
+  addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/include");
+
+  addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include");
+}