Index: lld/trunk/ELF/Driver.cpp
===================================================================
--- lld/trunk/ELF/Driver.cpp
+++ lld/trunk/ELF/Driver.cpp
@@ -611,6 +611,13 @@
   return true;
 }
 
+static int parseInt(StringRef S, opt::Arg *Arg) {
+  int V = 0;
+  if (!to_integer(S, V, 10))
+    error(Arg->getSpelling() + ": number expected, but got '" + S + "'");
+  return V;
+}
+
 // Initializes Config members by the command line options.
 void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->AllowMultipleDefinition =
@@ -694,9 +701,25 @@
   Config->ZText = !hasZOption(Args, "notext");
   Config->ZWxneeded = hasZOption(Args, "wxneeded");
 
+  for (auto *Arg : Args.filtered(OPT_plugin_opt, OPT_plugin_opt_eq)) {
+    StringRef S = Arg->getValue();
+    if (S == "disable-verify")
+      Config->DisableVerify = true;
+    else if (S == "save-temps")
+      Config->SaveTemps = true;
+    else if (S.startswith("O"))
+      Config->LTOO = parseInt(S.substr(1), Arg);
+    else if (S.startswith("lto-partitions="))
+      Config->LTOPartitions = parseInt(S.substr(15), Arg);
+    else if (S.startswith("jobs="))
+      Config->ThinLTOJobs = parseInt(S.substr(5), Arg);
+    // Ignore some options always passed by gcc.
+    else if (!S.startswith("/") && !S.startswith("-fresolution=") &&
+             !S.startswith("-pass-through="))
+      error(Arg->getSpelling() + ": unknown option: " + S);
+  }
   if (Config->LTOO > 3)
-    error("invalid optimization level for LTO: " +
-          Args.getLastArgValue(OPT_lto_O));
+    error("invalid optimization level for LTO: " + Twine(Config->LTOO));
   if (Config->LTOPartitions == 0)
     error("--lto-partitions: number of threads must be > 0");
   if (Config->ThinLTOJobs == 0)
Index: lld/trunk/ELF/Options.td
===================================================================
--- lld/trunk/ELF/Options.td
+++ lld/trunk/ELF/Options.td
@@ -362,6 +362,8 @@
   HelpText<"YAML output file for optimization remarks">;
 def opt_remarks_with_hotness: Flag<["--"], "opt-remarks-with-hotness">,
   HelpText<"Include hotness informations in the optimization remarks file">;
+defm plugin_opt: Eq<"plugin-opt">,
+  HelpText<"specifies LTO options for compatibility with GNU linkers">;
 def save_temps: F<"save-temps">;
 def thinlto_cache_dir: J<"thinlto-cache-dir=">,
   HelpText<"Path to ThinLTO cached object file directory">;
@@ -378,8 +380,6 @@
 // --version output.
 def plugin: S<"plugin">;
 def plugin_eq: J<"plugin=">;
-def plugin_opt: S<"plugin-opt">;
-def plugin_opt_eq: J<"plugin-opt=">;
 
 // Options listed below are silently ignored for now for compatibility.
 def allow_shlib_undefined: F<"allow-shlib-undefined">;
Index: lld/trunk/test/ELF/basic.s
===================================================================
--- lld/trunk/test/ELF/basic.s
+++ lld/trunk/test/ELF/basic.s
@@ -246,7 +246,9 @@
 # UNKNOWN_EMUL: unknown emulation: wrong_emul_fbsd
 
 # RUN: not ld.lld %t --lto-partitions=0 2>&1 | FileCheck --check-prefix=NOTHREADS %s
+# RUN: not ld.lld %t --plugin-opt=lto-partitions=0 2>&1 | FileCheck --check-prefix=NOTHREADS %s
 # NOTHREADS: --lto-partitions: number of threads must be > 0
 
 # RUN: not ld.lld %t --thinlto-jobs=0 2>&1 | FileCheck --check-prefix=NOTHREADSTHIN %s
+# RUN: not ld.lld %t --plugin-opt=jobs=0 2>&1 | FileCheck --check-prefix=NOTHREADSTHIN %s
 # NOTHREADSTHIN: --thinlto-jobs: number of threads must be > 0
Index: lld/trunk/test/ELF/lto-plugin-ignore.s
===================================================================
--- lld/trunk/test/ELF/lto-plugin-ignore.s
+++ lld/trunk/test/ELF/lto-plugin-ignore.s
@@ -0,0 +1,5 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: ld.lld %t -plugin-opt=/foo/bar -plugin-opt=-fresolution=zed \
+# RUN:   -plugin-opt=-pass-through=-lgcc -o /dev/null
Index: lld/trunk/test/ELF/lto/opt-level.ll
===================================================================
--- lld/trunk/test/ELF/lto/opt-level.ll
+++ lld/trunk/test/ELF/lto/opt-level.ll
@@ -2,18 +2,31 @@
 ; RUN: llvm-as -o %t.o %s
 ; RUN: ld.lld -o %t0 -m elf_x86_64 -e main --lto-O0 %t.o
 ; RUN: llvm-nm %t0 | FileCheck --check-prefix=CHECK-O0 %s
+; RUN: ld.lld -o %t0 -m elf_x86_64 -e main --plugin-opt=O0 %t.o
+; RUN: llvm-nm %t0 | FileCheck --check-prefix=CHECK-O0 %s
 ; RUN: ld.lld -o %t2 -m elf_x86_64 -e main --lto-O2 %t.o
 ; RUN: llvm-nm %t2 | FileCheck --check-prefix=CHECK-O2 %s
 ; RUN: ld.lld -o %t2a -m elf_x86_64 -e main %t.o
 ; RUN: llvm-nm %t2a | FileCheck --check-prefix=CHECK-O2 %s
+; RUN: ld.lld -o %t2 -m elf_x86_64 -e main --plugin-opt=O2 %t.o
+; RUN: llvm-nm %t2 | FileCheck --check-prefix=CHECK-O2 %s
 
 ; Reject invalid optimization levels.
 ; RUN: not ld.lld -o %t3 -m elf_x86_64 -e main --lto-O6 %t.o 2>&1 | \
-; RUN:   FileCheck --check-prefix=INVALID %s
-; INVALID: invalid optimization level for LTO: 6
+; RUN:   FileCheck --check-prefix=INVALID1 %s
+; INVALID1: invalid optimization level for LTO: 6
+; RUN: not ld.lld -o %t3 -m elf_x86_64 -e main --plugin-opt=O6 %t.o 2>&1 | \
+; RUN:   FileCheck --check-prefix=INVALID1 %s
+; RUN: not ld.lld -o %t3 -m elf_x86_64 -e main --plugin-opt=Ofoo %t.o 2>&1 | \
+; RUN:   FileCheck --check-prefix=INVALID2 %s
+; INVALID2: --plugin-opt: number expected, but got 'foo'
+
 ; RUN: not ld.lld -o %t3 -m elf_x86_64 -e main --lto-O-1 %t.o 2>&1 | \
-; RUN:   FileCheck --check-prefix=INVALIDNEGATIVE %s
-; INVALIDNEGATIVE: invalid optimization level for LTO: -1
+; RUN:   FileCheck --check-prefix=INVALIDNEGATIVE1 %s
+; INVALIDNEGATIVE1: invalid optimization level for LTO: 4294967295
+; RUN: not ld.lld -o %t3 -m elf_x86_64 -e main --plugin-opt=O-1 %t.o 2>&1 | \
+; RUN:   FileCheck --check-prefix=INVALIDNEGATIVE2 %s
+; INVALIDNEGATIVE2: invalid optimization level for LTO: 4294967295
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
Index: lld/trunk/test/ELF/lto/save-temps.ll
===================================================================
--- lld/trunk/test/ELF/lto/save-temps.ll
+++ lld/trunk/test/ELF/lto/save-temps.ll
@@ -9,6 +9,13 @@
 ; RUN: llvm-nm a.out.lto.o | FileCheck %s
 ; RUN: llvm-dis a.out.0.0.preopt.bc
 
+; RUN: rm -f a.out a.out.lto.bc a.out.lto.o
+; RUN: ld.lld -shared -m elf_x86_64 %t.o %t2.o --plugin-opt=save-temps
+; RUN: llvm-nm a.out | FileCheck %s
+; RUN: llvm-nm a.out.0.0.preopt.bc | FileCheck %s
+; RUN: llvm-nm a.out.lto.o | FileCheck %s
+; RUN: llvm-dis a.out.0.0.preopt.bc
+
 target triple = "x86_64-unknown-linux-gnu"
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
Index: lld/trunk/test/ELF/lto/verify-invalid.ll
===================================================================
--- lld/trunk/test/ELF/lto/verify-invalid.ll
+++ lld/trunk/test/ELF/lto/verify-invalid.ll
@@ -4,6 +4,8 @@
 ; RUN:   2>&1 | FileCheck -check-prefix=DEFAULT %s
 ; RUN: ld.lld -m elf_x86_64 %t.o -o %t2 -mllvm -debug-pass=Arguments \
 ; RUN:   -disable-verify 2>&1 | FileCheck -check-prefix=DISABLE %s
+; RUN: ld.lld -m elf_x86_64 %t.o -o %t2 -mllvm -debug-pass=Arguments \
+; RUN:   --plugin-opt=disable-verify 2>&1 | FileCheck -check-prefix=DISABLE %s
 
 target triple = "x86_64-unknown-linux-gnu"
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"