[driver] Do not pass "-flavor old-gnu" option to LLD linker

[atanasyan]

Summary

The "-flavor old-gnu" option were introduced to enable old version of LLD ELF linker implementation. This option has been removed from the linker since LLD 3.9. I do not think that there is a real case when the latest version of Clang is used in combination with so obsoleted version of LLD linker. Now we can remove support of this option from the driver.

[echristo]

LGTM

[ruiu]

LGTM

[atanasyan]

Fixed by rL340845.

lib/Driver/ToolChains/Gnu.cpp

void tools::gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   // 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);
 
-  const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
-  if (llvm::sys::path::stem(Exec) == "lld") {
-    CmdArgs.push_back("-flavor");
-    CmdArgs.push_back("old-gnu");
-    CmdArgs.push_back("-target");
-    CmdArgs.push_back(Args.MakeArgString(getToolChain().getTripleString()));
-  }
-
   if (!D.SysRoot.empty())
     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
 
   if (IsPIE)
     CmdArgs.push_back("-pie");
 
   if (Args.hasArg(options::OPT_rdynamic))
     CmdArgs.push_back("-export-dynamic");
void tools::gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
 
   // Add OpenMP offloading linker script args if required.
   AddOpenMPLinkerScript(getToolChain(), C, Output, Inputs, Args, CmdArgs, JA);
 
   // Add HIP offloading linker script args if required.
   AddHIPLinkerScript(getToolChain(), C, Output, Inputs, Args, CmdArgs, JA,
                      *this);
 
+  const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
   C.addCommand(llvm::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
 }
 
 void tools::gnutools::Assembler::ConstructJob(Compilation &C,
                                               const JobAction &JA,
                                               const InputInfo &Output,
                                               const InputInfoList &Inputs,
                                               const ArgList &Args,