Use ld directly on linux. Changes from the previous try:

*) Try to detect as much as possible from the system itself, not the distro.
   This should make it easier to port to a new distro and more likely to
   work on a unknown one.
*) The distro enum now doesn't include the arch. Just use the existing
   host detection support in LLVM.
*) Correctly handle --sysroot.

A small regression is that now clang will pass bitcode file to the linker.
This is necessary for the gold plugin support to work.

It might be better to detect this at configure/cmake time, but doing it in
c++ first is a lot easier.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@118382 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 144 insertions, 0 deletions

diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 744b0ae661..4d6cbf747f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -3136,6 +3136,150 @@ void linuxtools::Assemble::ConstructJob(Compilation &C, const JobAction &JA,
   C.addCommand(new Command(JA, *this, Exec, CmdArgs));
 }
 
+void linuxtools::Link::ConstructJob(Compilation &C, const JobAction &JA,
+                                    const InputInfo &Output,
+                                    const InputInfoList &Inputs,
+                                    const ArgList &Args,
+                                    const char *LinkingOutput) const {
+  const toolchains::Linux& ToolChain =
+    static_cast<const toolchains::Linux&>(getToolChain());
+  const Driver &D = ToolChain.getDriver();
+  ArgStringList CmdArgs;
+
+  if (Arg *A = Args.getLastArg(options::OPT__sysroot_EQ)) {
+    CmdArgs.push_back("--sysroot");
+    CmdArgs.push_back(A->getValue(Args));
+  }
+
+  for (std::vector<std::string>::const_iterator i = ToolChain.ExtraOpts.begin(),
+         e = ToolChain.ExtraOpts.end();
+       i != e; ++i)
+    CmdArgs.push_back(i->c_str());
+
+  if (!Args.hasArg(options::OPT_static)) {
+    CmdArgs.push_back("--eh-frame-hdr");
+  }
+
+  CmdArgs.push_back("-m");
+  if (ToolChain.getArch() == llvm::Triple::x86)
+    CmdArgs.push_back("elf_i386");
+  else if (ToolChain.getArch() == llvm::Triple::arm)
+    CmdArgs.push_back("armelf_linux_eabi");
+  else
+    CmdArgs.push_back("elf_x86_64");
+
+  if (Args.hasArg(options::OPT_static)) {
+    if (ToolChain.getArch() == llvm::Triple::arm)
+      CmdArgs.push_back("-Bstatic");
+    else
+      CmdArgs.push_back("-static");
+  } else if (Args.hasArg(options::OPT_shared)) {
+    CmdArgs.push_back("-shared");
+  }
+
+  if (ToolChain.getArch() == llvm::Triple::arm ||
+      (!Args.hasArg(options::OPT_static) &&
+       !Args.hasArg(options::OPT_shared))) {
+    CmdArgs.push_back("-dynamic-linker");
+    if (ToolChain.getArch() == llvm::Triple::x86)
+      CmdArgs.push_back("/lib/ld-linux.so.2");
+    else if (ToolChain.getArch() == llvm::Triple::arm)
+      CmdArgs.push_back("/lib/ld-linux.so.3");
+    else
+      CmdArgs.push_back("/lib64/ld-linux-x86-64.so.2");
+  }
+
+  CmdArgs.push_back("-o");
+  CmdArgs.push_back(Output.getFilename());
+
+  if (!Args.hasArg(options::OPT_shared))
+    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt1.o")));
+
+  CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crti.o")));
+
+  const char *crtbegin;
+  if (Args.hasArg(options::OPT_static))
+    crtbegin = "crtbeginT.o";
+  else if (Args.hasArg(options::OPT_shared))
+    crtbegin = "crtbeginS.o";
+  else
+    crtbegin = "crtbegin.o";
+
+  CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtbegin)));
+
+  Args.AddAllArgs(CmdArgs, options::OPT_L);
+
+  const ToolChain::path_list Paths = ToolChain.getFilePaths();
+
+  for (ToolChain::path_list::const_iterator i = Paths.begin(),
+         e = Paths.end();
+       i != e; ++i) {
+    const std::string &s = *i;
+    CmdArgs.push_back(Args.MakeArgString(std::string("-L") + s));
+  }
+
+  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs);
+
+  if (D.CCCIsCXX) {
+    ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
+    CmdArgs.push_back("-lm");
+  }
+
+  if (Args.hasArg(options::OPT_static))
+    CmdArgs.push_back("--start-group");
+
+  if (!D.CCCIsCXX)
+    CmdArgs.push_back("-lgcc");
+
+  if (Args.hasArg(options::OPT_static)) {
+    if (D.CCCIsCXX)
+      CmdArgs.push_back("-lgcc");
+  } else {
+    if (!D.CCCIsCXX)
+      CmdArgs.push_back("--as-needed");
+    CmdArgs.push_back("-lgcc_s");
+    if (!D.CCCIsCXX)
+      CmdArgs.push_back("--no-as-needed");
+  }
+
+  if (Args.hasArg(options::OPT_static))
+    CmdArgs.push_back("-lgcc_eh");
+  else if (!Args.hasArg(options::OPT_shared) && D.CCCIsCXX)
+    CmdArgs.push_back("-lgcc");
+
+  CmdArgs.push_back("-lc");
+
+  if (Args.hasArg(options::OPT_static))
+    CmdArgs.push_back("--end-group");
+  else {
+    if (!D.CCCIsCXX)
+      CmdArgs.push_back("-lgcc");
+
+    if (!D.CCCIsCXX)
+      CmdArgs.push_back("--as-needed");
+    CmdArgs.push_back("-lgcc_s");
+    if (!D.CCCIsCXX)
+      CmdArgs.push_back("--no-as-needed");
+
+    if (!Args.hasArg(options::OPT_shared) && D.CCCIsCXX)
+      CmdArgs.push_back("-lgcc");
+  }
+
+  if (Args.hasArg(options::OPT_shared))
+    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtendS.o")));
+  else
+    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
+
+  CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtn.o")));
+
+  if (Args.hasArg(options::OPT_use_gold_plugin)) {
+    CmdArgs.push_back("-plugin");
+    std::string Plugin = ToolChain.getDriver().Dir + "/../lib/LLVMgold.so";
+    CmdArgs.push_back(Args.MakeArgString(Plugin));
+  }
+
+  C.addCommand(new Command(JA, *this, ToolChain.Linker.c_str(), CmdArgs));
+}
 
 void minix::Assemble::ConstructJob(Compilation &C, const JobAction &JA,
                                    const InputInfo &Output,