[clang] [Driver] Implement ToolChain on Haiku (PR #66038)

[Fangrui Song via cfe-commits]

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@@ -9,20 +9,145 @@
 #include "Haiku.h"
 #include "CommonArgs.h"
 #include "clang/Config/config.h"
+#include "clang/Driver/Compilation.h"
 #include "llvm/Support/Path.h"
 
 using namespace clang::driver;
+using namespace clang::driver::tools;
 using namespace clang::driver::toolchains;
 using namespace clang;
 using namespace llvm::opt;
 
+void haiku::Linker::ConstructJob(Compilation &C, const JobAction &JA,
+                                   const InputInfo &Output,
+                                   const InputInfoList &Inputs,
+                                   const ArgList &Args,
+                                   const char *LinkingOutput) const {
+  const toolchains::Haiku &ToolChain =
+      static_cast<const toolchains::Haiku &>(getToolChain());
+  const Driver &D = ToolChain.getDriver();
+  const llvm::Triple::ArchType Arch = ToolChain.getArch();
+  const bool Static = Args.hasArg(options::OPT_static);
+  const bool Shared = Args.hasArg(options::OPT_shared);
+  ArgStringList CmdArgs;
+
+  // Silence warning for "clang -g foo.o -o foo"
+  Args.ClaimAllArgs(options::OPT_g_Group);
+  // and "clang -emit-llvm foo.o -o foo"
+  Args.ClaimAllArgs(options::OPT_emit_llvm);
+  // and for "clang -w foo.o -o foo". Other warning options are already
+  // handled somewhere else.
+  Args.ClaimAllArgs(options::OPT_w);
+
+  // Silence warning for "clang -pie foo.o -o foo"
+  Args.ClaimAllArgs(options::OPT_pie);
+
+  if (!D.SysRoot.empty())
+    CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
+
+  CmdArgs.push_back("--eh-frame-hdr");
+  if (Static) {
+    CmdArgs.push_back("-Bstatic");
+  } else {
+    if (Args.hasArg(options::OPT_rdynamic))
+      CmdArgs.push_back("-export-dynamic");
+    if (Shared)
+      CmdArgs.push_back("-shared");
+    CmdArgs.push_back("--enable-new-dtags");
+  }
+
+  CmdArgs.push_back("-shared");
+
+  if (!Shared)
+    CmdArgs.push_back("--no-undefined");
+
+  if (Arch == llvm::Triple::riscv64)
+    CmdArgs.push_back("-X");
+
+  if (Output.isFilename()) {
+    CmdArgs.push_back("-o");
+    CmdArgs.push_back(Output.getFilename());
+  } else {
+    assert(Output.isNothing() && "Invalid output.");
----------------
MaskRay wrote:

This can be moved before `Output.isFilename()`

https://github.com/llvm/llvm-project/pull/66038