diff -r 4accc35cbfcf Include/pyatomic.h
--- a/Include/pyatomic.h	Tue Mar 17 10:49:17 2015 +0100
+++ b/Include/pyatomic.h	Tue Mar 17 12:22:11 2015 +0100
@@ -1,4 +1,5 @@
-#ifndef Py_LIMITED_API
+/* Issue #23644: pyatomic.h is incompatible with C++ */
+#if !defined(Py_LIMITED_API) && !defined(__cplusplus)
 #ifndef Py_ATOMIC_H
 #define Py_ATOMIC_H
 
@@ -6,10 +7,6 @@
 
 #include "pyconfig.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #if defined(HAVE_STD_ATOMIC)
 #include <stdatomic.h>
 #endif
@@ -250,9 +247,5 @@ static __inline__ void
 #define _Py_atomic_load_relaxed(ATOMIC_VAL) \
     _Py_atomic_load_explicit(ATOMIC_VAL, _Py_memory_order_relaxed)
 
-#ifdef __cplusplus
-}
-#endif
-
 #endif  /* Py_ATOMIC_H */
 #endif  /* Py_LIMITED_API */
diff -r 4accc35cbfcf Include/pystate.h
--- a/Include/pystate.h	Tue Mar 17 10:49:17 2015 +0100
+++ b/Include/pystate.h	Tue Mar 17 12:22:11 2015 +0100
@@ -174,12 +174,14 @@ PyAPI_FUNC(int) PyThreadState_SetAsyncEx
 /* Variable and macro for in-line access to current thread state */
 
 /* Assuming the current thread holds the GIL, this is the
-   PyThreadState for the current thread. */
-#ifndef Py_LIMITED_API
+   PyThreadState for the current thread.
+
+   Issue #23644: pyatomic.h is incompatible with C++. */
+#if !defined(Py_LIMITED_API) && !defined(__cplusplus)
 PyAPI_DATA(_Py_atomic_address) _PyThreadState_Current;
 #endif
 
-#if defined(Py_DEBUG) || defined(Py_LIMITED_API)
+#if defined(Py_DEBUG) || defined(Py_LIMITED_API) || defined(__cplusplus)
 #define PyThreadState_GET() PyThreadState_Get()
 #else
 #define PyThreadState_GET() \