Support cross compiling to arm on ubuntu.

[logan]

Besides, I feel it will be even better to add the test cases for arm-linux-gnueabi as well.

FYI. I have created a patch for this change:
https://github.com/loganchien/clang/compare/b0e00c2...630a9e3

test/Driver/linux-ld.c

260

It seems that SYSROOT/lib is not added to version control. Maybe you have to put a placeholder such as .keep?

e.g.
mkdir -p Inputs/x86-64_ubuntu_13.10/lib
touch Inputs/x86-64_ubuntu_13.10/lib/.keep
git add Inputs/x86-64_ubuntu_13.10/lib/.keep

262

It seems we can add two more checks after this line:
CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../.."
CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/usr/lib"

[• rafael]

Add a missing .keep

[• rafael]

Add a test for arm-linux-gnueabi

[• rafael]

Actually include the test for arm-linux-gnueabi.

[logan]

The changes related to Ubuntu LGTM now. I have verified the change on Ubuntu 12.04, 13.04, and 13.10. All of them are working without any problem. However, I am not familiar with Fedora. Any comments from Fedora users?

[• rafael]

• {F12432, layout=link}
• {F12431, layout=link}

[logan]

LGTM. Thanks for your work.

[• rafael]

Fixed in r193528.

lib/Driver/ToolChains.cpp

 static bool IsDebian(enum Distro Distro) {
   return Distro >= DebianLenny && Distro <= DebianJessie;
 }
 
 static bool IsUbuntu(enum Distro Distro) {
   return Distro >= UbuntuHardy && Distro <= UbuntuSaucy;
 }
 
-static Distro DetectDistro(llvm::Triple::ArchType Arch) {
+static Distro DetectDistro(StringRef Prefix, llvm::Triple::ArchType Arch) {
   OwningPtr<llvm::MemoryBuffer> File;
-  if (!llvm::MemoryBuffer::getFile("/etc/lsb-release", File)) {
+  if (!llvm::MemoryBuffer::getFile(Prefix + "/etc/lsb-release", File)) {
     StringRef Data = File.get()->getBuffer();
     SmallVector<StringRef, 8> Lines;
     Data.split(Lines, "\n");
     Distro Version = UnknownDistro;
     for (unsigned i = 0, s = Lines.size(); i != s; ++i)
       if (Version == UnknownDistro && Lines[i].startswith("DISTRIB_CODENAME="))
         Version = llvm::StringSwitch<Distro>(Lines[i].substr(17))
           .Case("hardy", UbuntuHardy)
           .Case("intrepid", UbuntuIntrepid)
           .Case("jaunty", UbuntuJaunty)
           .Case("karmic", UbuntuKarmic)
           .Case("lucid", UbuntuLucid)
           .Case("maverick", UbuntuMaverick)
           .Case("natty", UbuntuNatty)
           .Case("oneiric", UbuntuOneiric)
           .Case("precise", UbuntuPrecise)
           .Case("quantal", UbuntuQuantal)
           .Case("raring", UbuntuRaring)
           .Case("saucy", UbuntuSaucy)
           .Default(UnknownDistro);
     return Version;
   }
 
-  if (!llvm::MemoryBuffer::getFile("/etc/redhat-release", File)) {
+  if (!llvm::MemoryBuffer::getFile(Prefix + "/etc/redhat-release", File)) {
     StringRef Data = File.get()->getBuffer();
     if (Data.startswith("Fedora release"))
       return Fedora;
     else if (Data.startswith("Red Hat Enterprise Linux") &&
              Data.find("release 6") != StringRef::npos)
       return RHEL6;
     else if ((Data.startswith("Red Hat Enterprise Linux") ||
               Data.startswith("CentOS")) &&
              Data.find("release 5") != StringRef::npos)
       return RHEL5;
     else if ((Data.startswith("Red Hat Enterprise Linux") ||
               Data.startswith("CentOS")) &&
              Data.find("release 4") != StringRef::npos)
       return RHEL4;
     return UnknownDistro;
   }
 
-  if (!llvm::MemoryBuffer::getFile("/etc/debian_version", File)) {
+  if (!llvm::MemoryBuffer::getFile(Prefix + "/etc/debian_version", File)) {
     StringRef Data = File.get()->getBuffer();
     if (Data[0] == '5')
       return DebianLenny;
     else if (Data.startswith("squeeze/sid") || Data[0] == '6')
       return DebianSqueeze;
     else if (Data.startswith("wheezy/sid")  || Data[0] == '7')
       return DebianWheezy;
     else if (Data.startswith("jessie/sid")  || Data[0] == '8')
       return DebianJessie;
     return UnknownDistro;
   }
 
-  if (llvm::sys::fs::exists("/etc/SuSE-release"))
+  if (llvm::sys::fs::exists(Prefix + "/etc/SuSE-release"))
     return OpenSUSE;
 
-  if (llvm::sys::fs::exists("/etc/exherbo-release"))
+  if (llvm::sys::fs::exists(Prefix + "/etc/exherbo-release"))
     return Exherbo;
 
-  if (llvm::sys::fs::exists("/etc/arch-release"))
+  if (llvm::sys::fs::exists(Prefix + "/etc/arch-release"))
     return ArchLinux;
 
   return UnknownDistro;
 }
 
 /// \brief Get our best guess at the multiarch triple for a target.
 ///
 /// Debian-based systems are starting to use a multiarch setup where they use
static std::string getMultiarchTriple(const llvm::Triple TargetTriple,
   }
 }
 
 static void addPathIfExists(Twine Path, ToolChain::path_list &Paths) {
   if (llvm::sys::fs::exists(Path)) Paths.push_back(Path.str());
 }
 
 static StringRef getMultilibDir(const llvm::Triple &Triple,
+                                bool IsBiarch,
                                 const ArgList &Args) {
-  if (!isMipsArch(Triple.getArch()))
+  if (!isMipsArch(Triple.getArch())) {
+    if (!IsBiarch)
+      return "lib";
+
     return Triple.isArch32Bit() ? "lib32" : "lib64";
+  }
 
   // lib32 directory has a special meaning on MIPS targets.
   // It contains N32 ABI binaries. Use this folder if produce
   // code for N32 ABI only.
   if (hasMipsN32ABIArg(Args))
     return "lib32";
 
   return Triple.isArch32Bit() ? "lib" : "lib64";
Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
   // used to target i386.
   // FIXME: This seems unlikely to be Linux-specific.
   ToolChain::path_list &PPaths = getProgramPaths();
   PPaths.push_back(Twine(GCCInstallation.getParentLibPath() + "/../" +
                          GCCInstallation.getTriple().str() + "/bin").str());
 
   Linker = GetProgramPath("ld");
 
-  Distro Distro = DetectDistro(Arch);
+  Distro Distro = DetectDistro(SysRoot, Arch);
 
   if (IsOpenSUSE(Distro) || IsUbuntu(Distro)) {
     ExtraOpts.push_back("-z");
     ExtraOpts.push_back("relro");
   }
 
   if (Arch == llvm::Triple::arm || Arch == llvm::Triple::thumb)
     ExtraOpts.push_back("-X");
if (IsOpenSUSE(Distro))
     ExtraOpts.push_back("--enable-new-dtags");
 
   // The selection of paths to try here is designed to match the patterns which
   // the GCC driver itself uses, as this is part of the GCC-compatible driver.
   // This was determined by running GCC in a fake filesystem, creating all
   // possible permutations of these directories, and seeing which ones it added
   // to the link paths.
   path_list &Paths = getFilePaths();
+  bool IsBiarch;
+  if (IsRedhat(Distro))
+    IsBiarch = true;
+  else if (GCCInstallation.isValid())
+    IsBiarch = !GCCInstallation.getBiarchSuffix().empty();
+  else
+    IsBiarch = true; // FIXME: is this a reasonable fallback?
 
-  const std::string Multilib = getMultilibDir(Triple, Args);
+  const std::string Multilib = getMultilibDir(Triple, IsBiarch, Args);
   const std::string MultiarchTriple = getMultiarchTriple(Triple, SysRoot);
 
   // Add the multilib suffixed paths where they are available.
   if (GCCInstallation.isValid()) {
     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
     const std::string &LibPath = GCCInstallation.getParentLibPath();
 
     // Sourcery CodeBench MIPS toolchain holds some libraries under
Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
   // installations with strange symlinks.
   if (GCCInstallation.isValid()) {
     addPathIfExists(SysRoot + "/usr/lib/" + GCCInstallation.getTriple().str() +
                     "/../../" + Multilib, Paths);
 
     // Add the non-multilib suffixed paths (if potentially different).
     const std::string &LibPath = GCCInstallation.getParentLibPath();
     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
-    if (!GCCInstallation.getBiarchSuffix().empty())
+    if (IsBiarch)
       addPathIfExists(GCCInstallation.getInstallPath() +
                       GCCInstallation.getMultiLibSuffix(), Paths);
 
     // See comments above on the multilib variant for details of why this is
     // included even from outside the sysroot.
     addPathIfExists(LibPath + "/../" + GCCTriple.str() +
                     "/lib" + GCCInstallation.getMultiLibSuffix(), Paths);
 

test/Driver/Inputs/fedora_18_tree/etc/redhat-release

+Fedora release 18 (Spherical Cow)

test/Driver/Inputs/x86-64_ubuntu_13.10/etc/debian_version

+wheezy/sid

test/Driver/cross-linux.c

 // RUN:   | FileCheck --check-prefix=CHECK-MULTI32-I386 %s
 // CHECK-MULTI32-I386: "-cc1" "-triple" "i386-unknown-linux"
 // CHECK-MULTI32-I386: "{{.*}}/Inputs/multilib_32bit_linux_tree/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../i386-unknown-linux/bin{{/|\\}}as" "--32"
 // CHECK-MULTI32-I386: "{{.*}}/Inputs/multilib_32bit_linux_tree/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../i386-unknown-linux/bin{{/|\\}}ld"
 // CHECK-MULTI32-I386: "--sysroot=[[sysroot:.*/Inputs/basic_linux_tree]]"
 // CHECK-MULTI32-I386: "-m" "elf_i386"
 // CHECK-MULTI32-I386: "crti.o" "[[gcc_install:.*/Inputs/multilib_32bit_linux_tree/usr/lib/gcc/i386-unknown-linux/4.6.0]]{{/|\\\\}}crtbegin.o"
 // CHECK-MULTI32-I386: "-L[[gcc_install]]"
-// CHECK-MULTI32-I386: "-L[[gcc_install]]/../../../../i386-unknown-linux/lib/../lib32"
+// CHECK-MULTI32-I386: "-L[[gcc_install]]/../../../../i386-unknown-linux/lib/../lib"
 // CHECK-MULTI32-I386: "-L[[gcc_install]]/../../../../i386-unknown-linux/lib"
 // CHECK-MULTI32-I386: "-L[[sysroot]]/lib"
 // CHECK-MULTI32-I386: "-L[[sysroot]]/usr/lib"
 //
 // RUN: %clang -### -o %t %s 2>&1 -no-integrated-as \
 // RUN:   --gcc-toolchain=%S/Inputs/multilib_32bit_linux_tree/usr \
 // RUN:   --target=x86_64-unknown-linux \
 // RUN:   --sysroot=%S/Inputs/basic_linux_tree \

 // RUN:   | FileCheck --check-prefix=CHECK-MULTI64-X86-64 %s
 // CHECK-MULTI64-X86-64: "-cc1" "-triple" "x86_64-unknown-linux"
 // CHECK-MULTI64-X86-64: "{{.*}}/Inputs/multilib_64bit_linux_tree/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/bin{{/|\\}}as" "--64"
 // CHECK-MULTI64-X86-64: "{{.*}}/Inputs/multilib_64bit_linux_tree/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/bin{{/|\\}}ld"
 // CHECK-MULTI64-X86-64: "--sysroot=[[sysroot:.*/Inputs/basic_linux_tree]]"
 // CHECK-MULTI64-X86-64: "-m" "elf_x86_64"
 // CHECK-MULTI64-X86-64: "crti.o" "[[gcc_install:.*/Inputs/multilib_64bit_linux_tree/usr/lib/gcc/x86_64-unknown-linux/4.6.0]]{{/|\\\\}}crtbegin.o"
 // CHECK-MULTI64-X86-64: "-L[[gcc_install]]"
-// CHECK-MULTI64-X86-64: "-L[[gcc_install]]/../../../../x86_64-unknown-linux/lib/../lib64"
+// CHECK-MULTI64-X86-64: "-L[[gcc_install]]/../../../../x86_64-unknown-linux/lib/../lib"
 // CHECK-MULTI64-X86-64: "-L[[gcc_install]]/../../../../x86_64-unknown-linux/lib"
 // CHECK-MULTI64-X86-64: "-L[[sysroot]]/lib"
 // CHECK-MULTI64-X86-64: "-L[[sysroot]]/usr/lib"

test/Driver/linux-ld.c

 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     --target=i386-unknown-linux -m32 \
 // RUN:     --sysroot=%S/Inputs/multilib_32bit_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-32-TO-32 %s
 // CHECK-32-TO-32: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
 // CHECK-32-TO-32: "{{.*}}/usr/lib/gcc/i386-unknown-linux/4.6.0{{/|\\\\}}crtbegin.o"
 // CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0"
-// CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../i386-unknown-linux/lib/../lib32"
-// CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../lib32"
-// CHECK-32-TO-32: "-L[[SYSROOT]]/lib/../lib32"
-// CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/../lib32"
+// CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../i386-unknown-linux/lib/../lib"
+// CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../lib"
+// CHECK-32-TO-32: "-L[[SYSROOT]]/lib/../lib"
+// CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/../lib"
 // CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0/../../../../i386-unknown-linux/lib"
 // CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/i386-unknown-linux/4.6.0/../../.."
 // CHECK-32-TO-32: "-L[[SYSROOT]]/lib"
 // CHECK-32-TO-32: "-L[[SYSROOT]]/usr/lib"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     --target=i386-unknown-linux -m64 \
 // RUN:     --sysroot=%S/Inputs/multilib_32bit_linux_tree \

 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     --target=x86_64-unknown-linux -m64 \
 // RUN:     --sysroot=%S/Inputs/multilib_64bit_linux_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-64-TO-64 %s
 // CHECK-64-TO-64: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
 // CHECK-64-TO-64: "{{.*}}/usr/lib/gcc/x86_64-unknown-linux/4.6.0{{/|\\\\}}crtbegin.o"
 // CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0"
-// CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib/../lib64"
-// CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../lib64"
-// CHECK-64-TO-64: "-L[[SYSROOT]]/lib/../lib64"
-// CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/../lib64"
+// CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib/../lib"
+// CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../lib"
+// CHECK-64-TO-64: "-L[[SYSROOT]]/lib/../lib"
+// CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/../lib"
 // CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib"
 // CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../.."
 // CHECK-64-TO-64: "-L[[SYSROOT]]/lib"
 // CHECK-64-TO-64: "-L[[SYSROOT]]/usr/lib"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     --target=x86_64-unknown-linux -m32 \
 // RUN:     --sysroot=%S/Inputs/multilib_64bit_linux_tree \

 // CHECK-UBUNTU-12-04-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc/arm-linux-gnueabihf/4.6.3"
 // CHECK-UBUNTU-12-04-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc/arm-linux-gnueabihf/4.6.3/../../../arm-linux-gnueabihf"
 // CHECK-UBUNTU-12-04-ARM-HF: "-L[[SYSROOT]]/lib/arm-linux-gnueabihf"
 // CHECK-UBUNTU-12-04-ARM-HF: "-L[[SYSROOT]]/usr/lib/arm-linux-gnueabihf"
 // CHECK-UBUNTU-12-04-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc/arm-linux-gnueabihf/4.6.3/../../.."
 // CHECK-UBUNTU-12-04-ARM-HF: "{{.*}}/usr/lib/gcc/arm-linux-gnueabihf/4.6.3{{/|\\\\}}crtend.o"
 // CHECK-UBUNTU-12-04-ARM-HF: "{{.*}}/usr/lib/gcc/arm-linux-gnueabihf/4.6.3/../../../arm-linux-gnueabihf{{/|\\\\}}crtn.o"
 //
+// Check Ubuntu 13.10 on x86-64 targeting arm-linux-gnueabihf.
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     --target=arm-linux-gnueabihf \
+// RUN:     --sysroot=%S/Inputs/x86-64_ubuntu_13.10 \
+// RUN:   | FileCheck --check-prefix=CHECK-X86-64-UBUNTU-13-10-ARM-HF %s
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-dynamic-linker" "/lib/ld-linux-armhf.so.3"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "{{.*}}/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/lib/../lib/crt1.o"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "{{.*}}/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/lib/../lib/crti.o"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "{{.*}}/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/crtbegin.o"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/lib/../lib"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/lib/../lib"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/usr/lib/../lib"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "-L[[SYSROOT]]/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/lib"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "{{.*}}/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/crtend.o"
+// CHECK-X86-64-UBUNTU-13-10-ARM-HF: "{{.*}}/usr/lib/gcc-cross/arm-linux-gnueabihf/4.8/../../../../arm-linux-gnueabihf/lib/../lib/crtn.o"
+//
 // Check fedora 18 on arm.
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     --target=armv7-unknown-linux-gnueabihf \
 // RUN:     --sysroot=%S/Inputs/fedora_18_tree \
 // RUN:   | FileCheck --check-prefix=CHECK-FEDORA-18-ARM-HF %s
 // CHECK-FEDORA-18-ARM-HF: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
 // CHECK-FEDORA-18-ARM-HF: "{{.*}}/usr/lib/gcc/armv7hl-redhat-linux-gnueabi/4.7.2/../../..{{/|\\\\}}crt1.o"
 // CHECK-FEDORA-18-ARM-HF: "{{.*}}/usr/lib/gcc/armv7hl-redhat-linux-gnueabi/4.7.2/../../..{{/|\\\\}}crti.o"