Index: cfe/trunk/include/clang/Basic/LangOptions.def
===================================================================
--- cfe/trunk/include/clang/Basic/LangOptions.def
+++ cfe/trunk/include/clang/Basic/LangOptions.def
@@ -133,7 +133,7 @@
 LANGOPT(NoBuiltin         , 1, 0, "disable builtin functions")
 LANGOPT(NoMathBuiltin     , 1, 0, "disable math builtin functions")
 LANGOPT(GNUAsm            , 1, 1, "GNU-style inline assembly")
-LANGOPT(Coroutines        , 1, 0, "C++ coroutines")
+LANGOPT(CoroutinesTS      , 1, 0, "C++ coroutines TS")
 
 BENIGN_LANGOPT(ThreadsafeStatics , 1, 1, "thread-safe static initializers")
 LANGOPT(POSIXThreads      , 1, 0, "POSIX thread support")
Index: cfe/trunk/include/clang/Driver/CC1Options.td
===================================================================
--- cfe/trunk/include/clang/Driver/CC1Options.td
+++ cfe/trunk/include/clang/Driver/CC1Options.td
@@ -638,10 +638,6 @@
 def finclude_default_header : Flag<["-"], "finclude-default-header">,
   HelpText<"Include the default header file for OpenCL">;
 
-// C++ TSes.
-def fcoroutines : Flag<["-"], "fcoroutines">,
-  HelpText<"Enable support for the C++ Coroutines TS">;
-
 //===----------------------------------------------------------------------===//
 // Header Search Options
 //===----------------------------------------------------------------------===//
Index: cfe/trunk/include/clang/Driver/Options.td
===================================================================
--- cfe/trunk/include/clang/Driver/Options.td
+++ cfe/trunk/include/clang/Driver/Options.td
@@ -481,6 +481,13 @@
   Flags<[DriverOption, CC1Option]>,
   HelpText<"Disable generation of linker directives for automatic library linking">;
 
+// C++ Coroutines TS
+def fcoroutines_ts : Flag <["-"], "fcoroutines-ts">, Group<f_Group>,
+  Flags<[DriverOption, CC1Option]>,
+  HelpText<"Enable support for the C++ Coroutines TS">;
+def fno_coroutines_ts : Flag <["-"], "fno-coroutines-ts">, Group<f_Group>,
+  Flags<[DriverOption]>;
+
 def fembed_bitcode_EQ : Joined<["-"], "fembed-bitcode=">,
     Group<f_Group>, Flags<[DriverOption, CC1Option]>, MetaVarName<"<option>">,
     HelpText<"Embed LLVM bitcode (option: off, all, bitcode, marker)">;
Index: cfe/trunk/lib/Basic/IdentifierTable.cpp
===================================================================
--- cfe/trunk/lib/Basic/IdentifierTable.cpp
+++ cfe/trunk/lib/Basic/IdentifierTable.cpp
@@ -150,7 +150,7 @@
   if (LangOpts.ObjC2 && (Flags & KEYARC)) return KS_Enabled;
   if (LangOpts.ObjC2 && (Flags & KEYOBJC2)) return KS_Enabled;
   if (LangOpts.ConceptsTS && (Flags & KEYCONCEPTS)) return KS_Enabled;
-  if (LangOpts.Coroutines && (Flags & KEYCOROUTINES)) return KS_Enabled;
+  if (LangOpts.CoroutinesTS && (Flags & KEYCOROUTINES)) return KS_Enabled;
   if (LangOpts.ModulesTS && (Flags & KEYMODULES)) return KS_Enabled;
   if (LangOpts.CPlusPlus && (Flags & KEYCXX11)) return KS_Future;
   return KS_Disabled;
Index: cfe/trunk/lib/Driver/Tools.cpp
===================================================================
--- cfe/trunk/lib/Driver/Tools.cpp
+++ cfe/trunk/lib/Driver/Tools.cpp
@@ -5416,6 +5416,12 @@
       CmdArgs.push_back("-fblocks-runtime-optional");
   }
 
+  if (Args.hasFlag(options::OPT_fcoroutines_ts, options::OPT_fno_coroutines_ts,
+                   false) &&
+      types::isCXX(InputType)) {
+    CmdArgs.push_back("-fcoroutines-ts");
+  }
+
   // -fmodules enables the use of precompiled modules (off by default).
   // Users can pass -fno-cxx-modules to turn off modules support for
   // C++/Objective-C++ programs.
Index: cfe/trunk/lib/Frontend/CompilerInvocation.cpp
===================================================================
--- cfe/trunk/lib/Frontend/CompilerInvocation.cpp
+++ cfe/trunk/lib/Frontend/CompilerInvocation.cpp
@@ -1916,7 +1916,7 @@
   Opts.Blocks = Args.hasArg(OPT_fblocks) || (Opts.OpenCL
     && Opts.OpenCLVersion >= 200);
   Opts.BlocksRuntimeOptional = Args.hasArg(OPT_fblocks_runtime_optional);
-  Opts.Coroutines = Args.hasArg(OPT_fcoroutines);
+  Opts.CoroutinesTS = Args.hasArg(OPT_fcoroutines_ts);
   Opts.ModulesTS = Args.hasArg(OPT_fmodules_ts);
   Opts.Modules = Args.hasArg(OPT_fmodules) || Opts.ModulesTS;
   Opts.ModulesStrictDeclUse = Args.hasArg(OPT_fmodules_strict_decluse);
Index: cfe/trunk/lib/Frontend/InitPreprocessor.cpp
===================================================================
--- cfe/trunk/lib/Frontend/InitPreprocessor.cpp
+++ cfe/trunk/lib/Frontend/InitPreprocessor.cpp
@@ -526,7 +526,7 @@
   // TS features.
   if (LangOpts.ConceptsTS)
     Builder.defineMacro("__cpp_experimental_concepts", "1");
-  if (LangOpts.Coroutines)
+  if (LangOpts.CoroutinesTS)
     Builder.defineMacro("__cpp_coroutines", "1");
 }
 
Index: cfe/trunk/lib/Sema/SemaDecl.cpp
===================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp
+++ cfe/trunk/lib/Sema/SemaDecl.cpp
@@ -11602,7 +11602,7 @@
   sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
   sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
 
-  if (getLangOpts().Coroutines && !getCurFunction()->CoroutineStmts.empty())
+  if (getLangOpts().CoroutinesTS && !getCurFunction()->CoroutineStmts.empty())
     CheckCompletedCoroutineBody(FD, Body);
 
   if (FD) {
Index: cfe/trunk/test/CodeGenCoroutines/microsoft-abi-operator-coawait.cpp
===================================================================
--- cfe/trunk/test/CodeGenCoroutines/microsoft-abi-operator-coawait.cpp
+++ cfe/trunk/test/CodeGenCoroutines/microsoft-abi-operator-coawait.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -triple x86_64-pc-windows-msvc18.0.0 -fcoroutines -emit-llvm %s -o - -std=c++14 -disable-llvm-passes | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-windows-msvc18.0.0 -fcoroutines-ts -emit-llvm %s -o - -std=c++14 -disable-llvm-passes | FileCheck %s
 struct no_suspend {
   bool await_ready() { return true; }
   template <typename F> void await_suspend(F) {}
Index: cfe/trunk/test/Driver/coroutines.c
===================================================================
--- cfe/trunk/test/Driver/coroutines.c
+++ cfe/trunk/test/Driver/coroutines.c
@@ -0,0 +1,6 @@
+// RUN: %clang -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// RUN: %clang -fcoroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// RUN: %clang -fno-coroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// RUN: %clang -fno-coroutines-ts -fcoroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// CHECK-NO-CORO-NOT: -fcoroutines-ts
+
Index: cfe/trunk/test/Driver/coroutines.cpp
===================================================================
--- cfe/trunk/test/Driver/coroutines.cpp
+++ cfe/trunk/test/Driver/coroutines.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// RUN: %clang -fcoroutines-ts -fno-coroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// RUN: %clang -fno-coroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-NO-CORO %s
+// CHECK-NO-CORO-NOT: -fcoroutines-ts
+
+// RUN: %clang -fcoroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-HAS-CORO  %s
+// RUN: %clang -fno-coroutines-ts -fcoroutines-ts -### %s 2>&1 | FileCheck -check-prefix=CHECK-HAS-CORO %s
+// CHECK-HAS-CORO: -fcoroutines-ts
+
Index: cfe/trunk/test/Lexer/coroutines.cpp
===================================================================
--- cfe/trunk/test/Lexer/coroutines.cpp
+++ cfe/trunk/test/Lexer/coroutines.cpp
@@ -1,5 +1,5 @@
 // RUN: %clang_cc1 -fsyntax-only %s
-// RUN: %clang_cc1 -fcoroutines -DCORO -fsyntax-only %s
+// RUN: %clang_cc1 -fcoroutines-ts -DCORO -fsyntax-only %s
 
 #ifdef CORO
 #define CORO_KEYWORD(NAME) _Static_assert(!__is_identifier(NAME), #NAME)
Index: cfe/trunk/test/Lexer/cxx-features.cpp
===================================================================
--- cfe/trunk/test/Lexer/cxx-features.cpp
+++ cfe/trunk/test/Lexer/cxx-features.cpp
@@ -5,7 +5,7 @@
 // RUN: %clang_cc1 -std=c++1z -fcxx-exceptions -fsized-deallocation -verify %s
 // RUN: %clang_cc1 -std=c++1z -fcxx-exceptions -fsized-deallocation -fconcepts-ts -DCONCEPTS_TS=1 -verify %s
 // RUN: %clang_cc1 -fno-rtti -verify %s -DNO_EXCEPTIONS -DNO_RTTI
-// RUN: %clang_cc1 -fcoroutines -DNO_EXCEPTIONS -DCOROUTINES -verify %s
+// RUN: %clang_cc1 -fcoroutines-ts -DNO_EXCEPTIONS -DCOROUTINES -verify %s
 
 // expected-no-diagnostics
 
Index: cfe/trunk/test/Parser/cxx1z-coroutines.cpp
===================================================================
--- cfe/trunk/test/Parser/cxx1z-coroutines.cpp
+++ cfe/trunk/test/Parser/cxx1z-coroutines.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -std=c++11 -fcoroutines %s -verify
+// RUN: %clang_cc1 -std=c++11 -fcoroutines-ts %s -verify
 
 template<typename T, typename U>
 U f(T t) {
Index: cfe/trunk/test/SemaCXX/coroutines.cpp
===================================================================
--- cfe/trunk/test/SemaCXX/coroutines.cpp
+++ cfe/trunk/test/SemaCXX/coroutines.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -std=c++14 -fcoroutines -verify %s
+// RUN: %clang_cc1 -std=c++14 -fcoroutines-ts -verify %s
 
 void no_coroutine_traits_bad_arg_await() {
   co_await a; // expected-error {{include <coroutine>}}