From 8e4e04b77176903e601af6e894f1a81907f0cd0b Mon Sep 17 00:00:00 2001
From: "Stephan T. Lavavej" <stl@microsoft.com>
Date: Mon, 17 Aug 2020 19:10:08 -0700
Subject: [PATCH] Update __cpp_lib_coroutine.

---
 stl/inc/yvals_core.h                          |  9 ++++++---
 .../VSO_0157762_feature_test_macros/test.cpp  | 19 +++++++++++++++++++
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/stl/inc/yvals_core.h b/stl/inc/yvals_core.h
index 9fa892ff5e..3043b0eec6 100644
--- a/stl/inc/yvals_core.h
+++ b/stl/inc/yvals_core.h
@@ -172,7 +172,6 @@
 //     (partially implemented)
 // P0898R3 Standard Library Concepts
 // P0912R5 Library Support For Coroutines
-//     (partially implemented, missing noop coroutines)
 // P0919R3 Heterogeneous Lookup For Unordered Containers
 // P0966R1 string::reserve() Should Not Shrink
 // P1001R2 execution::unseq
@@ -1169,8 +1168,12 @@
 #define __cpp_lib_constexpr_tuple       201811L
 #define __cpp_lib_constexpr_utility     201811L
 
-#ifdef __cpp_impl_coroutine // TRANSITION, VS 2019 16.8 Preview 3
-#define __cpp_lib_coroutine 197000L
+#ifdef __cpp_impl_coroutine // TRANSITION, Clang and EDG coroutine support
+#if __cpp_impl_coroutine >= 201902L
+#define __cpp_lib_coroutine 201902L
+#else // ^^^ __cpp_impl_coroutine >= 201902L ^^^ / vvv __cpp_impl_coroutine < 201902L vvv
+#define __cpp_lib_coroutine 197000L // TRANSITION, VS 2019 16.8 Preview 4
+#endif // ^^^ __cpp_impl_coroutine < 201902L ^^^
 #endif // __cpp_impl_coroutine
 
 #define __cpp_lib_destroying_delete            201806L
diff --git a/tests/std/tests/VSO_0157762_feature_test_macros/test.cpp b/tests/std/tests/VSO_0157762_feature_test_macros/test.cpp
index 9bad3e0c1d..c3eaa1b577 100644
--- a/tests/std/tests/VSO_0157762_feature_test_macros/test.cpp
+++ b/tests/std/tests/VSO_0157762_feature_test_macros/test.cpp
@@ -481,6 +481,25 @@ STATIC_ASSERT(__cpp_lib_constexpr_utility == 201811L);
 #endif
 #endif
 
+#if _HAS_CXX20 && defined(__cpp_impl_coroutine) // TRANSITION, Clang and EDG coroutine support
+#if __cpp_impl_coroutine >= 201902L
+#define ExpectedCppLibCoroutine 201902L
+#else
+#define ExpectedCppLibCoroutine 197000L // TRANSITION, VS 2019 16.8 Preview 4
+#endif
+#ifndef __cpp_lib_coroutine
+#error __cpp_lib_coroutine is not defined
+#elif __cpp_lib_coroutine != ExpectedCppLibCoroutine
+#error __cpp_lib_coroutine is not ExpectedCppLibCoroutine
+#else
+STATIC_ASSERT(__cpp_lib_coroutine == ExpectedCppLibCoroutine);
+#endif
+#else
+#ifdef __cpp_lib_coroutine
+#error __cpp_lib_coroutine is defined
+#endif
+#endif
+
 #if _HAS_CXX20
 #ifndef __cpp_lib_destroying_delete
 #error __cpp_lib_destroying_delete is not defined