diff --git a/clang/lib/Headers/adxintrin.h b/clang/lib/Headers/adxintrin.h
--- a/clang/lib/Headers/adxintrin.h
+++ b/clang/lib/Headers/adxintrin.h
@@ -17,56 +17,69 @@
 /* Define the default attributes for the functions in this file. */
 #define __DEFAULT_FN_ATTRS __attribute__((__always_inline__, __nodebug__))
 
+/* Use C++ inline semantics in C++, GNU inline for C mode. */
+#if defined(__cplusplus)
+#define __INLINE __inline
+#else
+#define __INLINE static __inline
+#endif
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
 /* Intrinsics that are available only if __ADX__ defined */
-static __inline unsigned char __attribute__((__always_inline__, __nodebug__, __target__("adx")))
-_addcarryx_u32(unsigned char __cf, unsigned int __x, unsigned int __y,
-               unsigned int *__p)
-{
+__INLINE unsigned char
+    __attribute__((__always_inline__, __nodebug__, __target__("adx")))
+    _addcarryx_u32(unsigned char __cf, unsigned int __x, unsigned int __y,
+                   unsigned int *__p) {
   return __builtin_ia32_addcarryx_u32(__cf, __x, __y, __p);
 }
 
 #ifdef __x86_64__
-static __inline unsigned char __attribute__((__always_inline__, __nodebug__, __target__("adx")))
-_addcarryx_u64(unsigned char __cf, unsigned long long __x,
-               unsigned long long __y, unsigned long long  *__p)
-{
+__INLINE unsigned char
+    __attribute__((__always_inline__, __nodebug__, __target__("adx")))
+    _addcarryx_u64(unsigned char __cf, unsigned long long __x,
+                   unsigned long long __y, unsigned long long *__p) {
   return __builtin_ia32_addcarryx_u64(__cf, __x, __y, __p);
 }
 #endif
 
 /* Intrinsics that are also available if __ADX__ undefined */
-static __inline unsigned char __DEFAULT_FN_ATTRS
-_addcarry_u32(unsigned char __cf, unsigned int __x, unsigned int __y,
-              unsigned int *__p)
-{
+__INLINE unsigned char __DEFAULT_FN_ATTRS _addcarry_u32(unsigned char __cf,
+                                                        unsigned int __x,
+                                                        unsigned int __y,
+                                                        unsigned int *__p) {
   return __builtin_ia32_addcarryx_u32(__cf, __x, __y, __p);
 }
 
 #ifdef __x86_64__
-static __inline unsigned char __DEFAULT_FN_ATTRS
+__INLINE unsigned char __DEFAULT_FN_ATTRS
 _addcarry_u64(unsigned char __cf, unsigned long long __x,
-              unsigned long long __y, unsigned long long  *__p)
-{
+              unsigned long long __y, unsigned long long *__p) {
   return __builtin_ia32_addcarryx_u64(__cf, __x, __y, __p);
 }
 #endif
 
-static __inline unsigned char __DEFAULT_FN_ATTRS
-_subborrow_u32(unsigned char __cf, unsigned int __x, unsigned int __y,
-              unsigned int *__p)
-{
+__INLINE unsigned char __DEFAULT_FN_ATTRS _subborrow_u32(unsigned char __cf,
+                                                         unsigned int __x,
+                                                         unsigned int __y,
+                                                         unsigned int *__p) {
   return __builtin_ia32_subborrow_u32(__cf, __x, __y, __p);
 }
 
 #ifdef __x86_64__
-static __inline unsigned char __DEFAULT_FN_ATTRS
+__INLINE unsigned char __DEFAULT_FN_ATTRS
 _subborrow_u64(unsigned char __cf, unsigned long long __x,
-               unsigned long long __y, unsigned long long  *__p)
-{
+               unsigned long long __y, unsigned long long *__p) {
   return __builtin_ia32_subborrow_u64(__cf, __x, __y, __p);
 }
 #endif
 
+#if defined(__cplusplus)
+}
+#endif
+
 #undef __DEFAULT_FN_ATTRS
 
 #endif /* __ADXINTRIN_H */