diff --git a/clang/docs/ClangCommandLineReference.rst b/clang/docs/ClangCommandLineReference.rst
--- a/clang/docs/ClangCommandLineReference.rst
+++ b/clang/docs/ClangCommandLineReference.rst
@@ -212,6 +212,10 @@
 
 Trivial automatic variable initialization to zero is only here for benchmarks, it'll eventually be removed, and I'm OK with that because I'm only using it to benchmark
 
+.. option:: --end-no-unused-arguments
+
+Start emitting warnings for unused driver arguments
+
 .. option:: -exported\_symbols\_list <arg>
 
 .. option:: -faligned-new=<arg>
@@ -663,6 +667,10 @@
 
 .. option:: -single\_module
 
+.. option:: --start-no-unused-arguments
+
+Don't emit warnings about unused arguments for the following arguments
+
 .. option:: -static-libgcc
 
 .. option:: -static-libsan
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1076,6 +1076,8 @@
 def emit_merged_ifs : Flag<["-"], "emit-merged-ifs">,
   Flags<[CC1Option]>, Group<Action_Group>,
   HelpText<"Generate Interface Stub Files, emit merged text not binary.">;
+def end_no_unused_arguments : Flag<["--"], "end-no-unused-arguments">, Flags<[CoreOption]>,
+  HelpText<"Start emitting warnings for unused driver arguments">;
 def interface_stub_version_EQ : JoinedOrSeparate<["-"], "interface-stub-version=">, Flags<[CC1Option]>;
 def exported__symbols__list : Separate<["-"], "exported_symbols_list">;
 def e : JoinedOrSeparate<["-"], "e">, Flags<[LinkerInput]>, Group<Link_Group>;
@@ -3913,6 +3915,8 @@
 def single__module : Flag<["-"], "single_module">;
 def specs_EQ : Joined<["-", "--"], "specs=">, Group<Link_Group>;
 def specs : Separate<["-", "--"], "specs">, Flags<[Unsupported]>;
+def start_no_unused_arguments : Flag<["--"], "start-no-unused-arguments">, Flags<[CoreOption]>,
+  HelpText<"Don't emit warnings about unused arguments for the following arguments">;
 def static_libgcc : Flag<["-"], "static-libgcc">;
 def static_libstdcxx : Flag<["-"], "static-libstdc++">;
 def static : Flag<["-", "--"], "static">, Group<Link_Group>, Flags<[NoArgumentUnused]>;
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -367,7 +367,20 @@
   bool HasNostdlib = Args.hasArg(options::OPT_nostdlib);
   bool HasNostdlibxx = Args.hasArg(options::OPT_nostdlibxx);
   bool HasNodefaultlib = Args.hasArg(options::OPT_nodefaultlibs);
+  bool IgnoreUnused = false;
   for (Arg *A : Args) {
+    if (IgnoreUnused)
+      A->claim();
+
+    if (A->getOption().matches(options::OPT_start_no_unused_arguments)) {
+      IgnoreUnused = true;
+      continue;
+    }
+    if (A->getOption().matches(options::OPT_end_no_unused_arguments)) {
+      IgnoreUnused = false;
+      continue;
+    }
+
     // Unfortunately, we have to parse some forwarding options (-Xassembler,
     // -Xlinker, -Xpreprocessor) because we either integrate their functionality
     // (assembler and preprocessor), or bypass a previous driver ('collect2').
diff --git a/clang/test/Driver/diagnostics.c b/clang/test/Driver/diagnostics.c
--- a/clang/test/Driver/diagnostics.c
+++ b/clang/test/Driver/diagnostics.c
@@ -1,9 +1,53 @@
 // Parse diagnostic arguments in the driver
-// PR12181
 
-// RUN: not %clang -target x86_64-apple-darwin10 \
-// RUN:   -fsyntax-only -fzyzzybalubah \
-// RUN:   -Werror=unused-command-line-argument %s
+// Exactly which arguments are warned about and which aren't differ based
+// on what target is selected. -stdlib= and -fuse-ld= emit diagnostics when
+// compiling C code, for e.g. *-linux-gnu. Linker inputs, like -lfoo, emit
+// diagnostics when only compiling for all targets.
 
-// RUN: not %clang -target x86_64-apple-darwin10 \
-// RUN:   -fsyntax-only -fzyzzybalubah -Werror %s
+// This is normally a non-fatal warning:
+// RUN: %clang --target=x86_64-apple-darwin10 \
+// RUN:   -fsyntax-only -lfoo %s 2>&1 | FileCheck %s
+
+// Either with a specific -Werror=unused.. or a blanket -Werror, this
+// causes the command to fail.
+// RUN: not %clang --target=x86_64-apple-darwin10 \
+// RUN:   -fsyntax-only -lfoo \
+// RUN:   -Werror=unused-command-line-argument %s 2>&1 | FileCheck %s
+
+// RUN: not %clang --target=x86_64-apple-darwin10 \
+// RUN:   -fsyntax-only -lfoo -Werror %s 2>&1 | FileCheck %s
+
+// With a specific -Wno-..., no diagnostic should be printed.
+// RUN: %clang --target=x86_64-apple-darwin10 \
+// RUN:   -fsyntax-only -lfoo -Werror \
+// RUN:   -Wno-unused-command-line-argument %s 2>&1 | count 0
+
+// With -Qunused-arguments, no diagnostic should be printed.
+// RUN: %clang --target=x86_64-apple-darwin10 \
+// RUN:   -fsyntax-only -lfoo -Werror \
+// RUN:   -Qunused-arguments %s 2>&1 | count 0
+
+// With the argument enclosed in --{start,end}-no-unused-arguments,
+// there's no diagnostic.
+// RUN: %clang --target=x86_64-apple-darwin10 -fsyntax-only \
+// RUN:   --start-no-unused-arguments -lfoo --end-no-unused-arguments \
+// RUN:   -Werror %s 2>&1 | count 0
+
+// With --{start,end}-no-unused-argument around a different argument, it
+// still warns about the unused argument.
+// RUN: not %clang --target=x86_64-apple-darwin10 \
+// RUN:   --start-no-unused-arguments -fsyntax-only --end-no-unused-arguments \
+// RUN:   -lfoo -Werror %s 2>&1 | FileCheck %s
+
+// Test clang-cl warning about unused linker options.
+// RUN: not %clang_cl -fsyntax-only /WX %s \
+// RUN:   -link 2>&1 | FileCheck %s --check-prefix=CL-WARNING
+
+// Test clang-cl ignoring the warning with --start-no-unused-arguments.
+// RUN: %clang_cl -fsyntax-only /WX %s \
+// RUN:   --start-no-unused-arguments -link --end-no-unused-arguments 2>&1 | count 0
+
+// CHECK: -lfoo: 'linker' input unused
+
+// CL-WARNING: argument unused during compilation: '-link'