Index: llvm/test/tools/llvm-objcopy/basic-only-keep-debug.test
===================================================================
--- /dev/null
+++ llvm/test/tools/llvm-objcopy/basic-only-keep-debug.test
@@ -0,0 +1,20 @@
+# NOTE: This test is only intended to be valid as long as --only-keep-debug is
+#       implemented as a NOP. This test should fail when that changes and you
+#       will need to update this test.
+
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-objcopy --only-keep-debug %t %t3
+# RUN: cmp %t2 %t3
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    Content:         "DEADBEEF"
Index: llvm/tools/llvm-objcopy/ObjcopyOpts.td
===================================================================
--- llvm/tools/llvm-objcopy/ObjcopyOpts.td
+++ llvm/tools/llvm-objcopy/ObjcopyOpts.td
@@ -83,3 +83,5 @@
                        HelpText<"Remove symbol <symbol>">;
 def N : JoinedOrSeparate<["-"], "N">,
         Alias<strip_symbol>;
+def only_keep_debug : Flag<["-", "--"], "only-keep-debug">,
+                          HelpText<"Currently ignored. Only for compaitability with GNU objcopy.">;
Index: llvm/tools/llvm-objcopy/llvm-objcopy.cpp
===================================================================
--- llvm/tools/llvm-objcopy/llvm-objcopy.cpp
+++ llvm/tools/llvm-objcopy/llvm-objcopy.cpp
@@ -159,6 +159,7 @@
   bool LocalizeHidden = false;
   bool Weaken = false;
   bool DiscardAll = false;
+  bool OnlyKeepDebug = false;
 };
 
 using SectionPred = std::function<bool(const SectionBase &Sec)>;
@@ -477,6 +478,7 @@
   Config.LocalizeHidden = InputArgs.hasArg(OBJCOPY_localize_hidden);
   Config.Weaken = InputArgs.hasArg(OBJCOPY_weaken);
   Config.DiscardAll = InputArgs.hasArg(OBJCOPY_discard_all);
+  Config.OnlyKeepDebug = InputArgs.hasArg(OBJCOPY_only_keep_debug);
   for (auto Arg : InputArgs.filtered(OBJCOPY_localize_symbol))
     Config.SymbolsToLocalize.push_back(Arg->getValue());
   for (auto Arg : InputArgs.filtered(OBJCOPY_globalize_symbol))