diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 2ef609831637e..de0d32f68253a 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1011,6 +1011,9 @@ def : Flag<["-"], "Xcompiler">, IgnoredGCCCompat;
 def Z_Flag : Flag<["-"], "Z">, Group<Link_Group>;
 def all__load : Flag<["-"], "all_load">;
 def allowable__client : Separate<["-"], "allowable_client">;
+def allow_unrecognized_arguments : Flag<["--"], "allow-unrecognized-arguments">,
+    Visibility<[ClangOption, CLOption]>,
+    HelpText<"Ignore unrecognized command-line arguments instead of reporting an error.">;
 def ansi : Flag<["-", "--"], "ansi">, Group<CompileOnly_Group>;
 def arch__errors__fatal : Flag<["-"], "arch_errors_fatal">;
 def arch : Separate<["-"], "arch">, Flags<[NoXarchOption,TargetSpecific]>;
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 85a1335785542..4f2ac9ba8271c 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -303,29 +303,31 @@ InputArgList Driver::ParseArgStrings(ArrayRef<const char *> ArgStrings,
     }
   }
 
-  for (const Arg *A : Args.filtered(options::OPT_UNKNOWN)) {
-    unsigned DiagID;
-    auto ArgString = A->getAsString(Args);
-    std::string Nearest;
-    if (getOpts().findNearest(ArgString, Nearest, VisibilityMask) > 1) {
-      if (!IsCLMode() &&
-          getOpts().findExact(ArgString, Nearest,
-                              llvm::opt::Visibility(options::CC1Option))) {
-        DiagID = diag::err_drv_unknown_argument_with_suggestion;
-        Diags.Report(DiagID) << ArgString << "-Xclang " + Nearest;
+  if (!Args.hasArg(options::OPT_allow_unrecognized_arguments)) {
+    for (const Arg *A : Args.filtered(options::OPT_UNKNOWN)) {
+      unsigned DiagID;
+      auto ArgString = A->getAsString(Args);
+      std::string Nearest;
+      if (getOpts().findNearest(ArgString, Nearest, VisibilityMask) > 1) {
+        if (!IsCLMode() &&
+            getOpts().findExact(ArgString, Nearest,
+                                llvm::opt::Visibility(options::CC1Option))) {
+          DiagID = diag::err_drv_unknown_argument_with_suggestion;
+          Diags.Report(DiagID) << ArgString << "-Xclang " + Nearest;
+        } else {
+          DiagID = IsCLMode() ? diag::warn_drv_unknown_argument_clang_cl
+                              : diag::err_drv_unknown_argument;
+          Diags.Report(DiagID) << ArgString;
+        }
       } else {
-        DiagID = IsCLMode() ? diag::warn_drv_unknown_argument_clang_cl
-                            : diag::err_drv_unknown_argument;
-        Diags.Report(DiagID) << ArgString;
+        DiagID = IsCLMode()
+                     ? diag::warn_drv_unknown_argument_clang_cl_with_suggestion
+                     : diag::err_drv_unknown_argument_with_suggestion;
+        Diags.Report(DiagID) << ArgString << Nearest;
       }
-    } else {
-      DiagID = IsCLMode()
-                   ? diag::warn_drv_unknown_argument_clang_cl_with_suggestion
-                   : diag::err_drv_unknown_argument_with_suggestion;
-      Diags.Report(DiagID) << ArgString << Nearest;
+      ContainsError |= Diags.getDiagnosticLevel(DiagID, SourceLocation()) >
+                       DiagnosticsEngine::Warning;
     }
-    ContainsError |= Diags.getDiagnosticLevel(DiagID, SourceLocation()) >
-                     DiagnosticsEngine::Warning;
   }
 
   for (const Arg *A : Args.filtered(options::OPT_o)) {
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 422375240bab6..0ba29db471617 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -4991,15 +4991,17 @@ bool CompilerInvocation::CreateFromArgsImpl(
     Diags.Report(diag::err_drv_missing_argument)
         << Args.getArgString(MissingArgIndex) << MissingArgCount;
 
-  // Issue errors on unknown arguments.
-  for (const auto *A : Args.filtered(OPT_UNKNOWN)) {
-    auto ArgString = A->getAsString(Args);
-    std::string Nearest;
-    if (Opts.findNearest(ArgString, Nearest, VisibilityMask) > 1)
-      Diags.Report(diag::err_drv_unknown_argument) << ArgString;
-    else
-      Diags.Report(diag::err_drv_unknown_argument_with_suggestion)
-          << ArgString << Nearest;
+  if (!Args.hasArg(options::OPT_allow_unrecognized_arguments)) {
+    // Issue errors on unknown arguments.
+    for (const auto *A : Args.filtered(OPT_UNKNOWN)) {
+      auto ArgString = A->getAsString(Args);
+      std::string Nearest;
+      if (Opts.findNearest(ArgString, Nearest, VisibilityMask) > 1)
+        Diags.Report(diag::err_drv_unknown_argument) << ArgString;
+      else
+        Diags.Report(diag::err_drv_unknown_argument_with_suggestion)
+            << ArgString << Nearest;
+    }
   }
 
   ParseFileSystemArgs(Res.getFileSystemOpts(), Args, Diags);
diff --git a/clang/test/Driver/unsupported-option.c b/clang/test/Driver/unsupported-option.c
index 7234e52571582..465f1879b31c8 100644
--- a/clang/test/Driver/unsupported-option.c
+++ b/clang/test/Driver/unsupported-option.c
@@ -32,3 +32,7 @@
 // RUN: not %clang -c -Qunused-arguments --target=aarch64-- -mfpu=crypto-neon-fp-armv8 %s 2>&1 \
 // RUN:   | FileCheck %s --check-prefix=QUNUSED_ARGUMENTS
 // QUNUSED_ARGUMENTS: error: unsupported option '-mfpu=' for target 'aarch64--'
+
+// RUN: %clang %s -invalid --allow-unrecognized-arguments -### 2>&1 | \
+// RUN: FileCheck %s --check-prefix=UNKNOWN_ARGUMENT
+// UNKNOWN_ARGUMENT: warning: argument unused during compilation: '-invalid'