diff --git a/clang/lib/Headers/arm_acle.h b/clang/lib/Headers/arm_acle.h
--- a/clang/lib/Headers/arm_acle.h
+++ b/clang/lib/Headers/arm_acle.h
@@ -22,31 +22,43 @@
 
 /* 8 SYNCHRONIZATION, BARRIER AND HINT INTRINSICS */
 /* 8.3 Memory barriers */
-#if !defined(_MSC_VER)
+#if !__has_builtin(__dmb)
 #define __dmb(i) __builtin_arm_dmb(i)
+#endif
+#if !__has_builtin(__dsb)
 #define __dsb(i) __builtin_arm_dsb(i)
+#endif
+#if !__has_builtin(__isb)
 #define __isb(i) __builtin_arm_isb(i)
 #endif
 
 /* 8.4 Hints */
 
-#if !defined(_MSC_VER)
+#if !__has_builtin(__wfi)
 static __inline__ void __attribute__((__always_inline__, __nodebug__)) __wfi(void) {
   __builtin_arm_wfi();
 }
+#endif
 
+#if !__has_builtin(__wfe)
 static __inline__ void __attribute__((__always_inline__, __nodebug__)) __wfe(void) {
   __builtin_arm_wfe();
 }
+#endif
 
+#if !__has_builtin(__sev)
 static __inline__ void __attribute__((__always_inline__, __nodebug__)) __sev(void) {
   __builtin_arm_sev();
 }
+#endif
 
+#if !__has_builtin(__sevl)
 static __inline__ void __attribute__((__always_inline__, __nodebug__)) __sevl(void) {
   __builtin_arm_sevl();
 }
+#endif
 
+#if !__has_builtin(__yield)
 static __inline__ void __attribute__((__always_inline__, __nodebug__)) __yield(void) {
   __builtin_arm_yield();
 }
diff --git a/clang/test/Headers/arm-acle-header.c b/clang/test/Headers/arm-acle-header.c
--- a/clang/test/Headers/arm-acle-header.c
+++ b/clang/test/Headers/arm-acle-header.c
@@ -6,6 +6,7 @@
 // RUN: %clang_cc1 -x c++ -triple thumbv7-windows -target-cpu cortex-a15 -fsyntax-only -ffreestanding %s
 // RUN: %clang_cc1 -x c++ -triple thumbv7-windows -target-cpu cortex-a15 -fsyntax-only -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=19.11 %s
 // RUN: %clang_cc1 -x c++ -triple aarch64-windows -target-cpu cortex-a53 -fsyntax-only -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=19.11 %s
+// RUN: %clang_cc1 -x c++ -triple arm64-apple-ios -target-cpu apple-a7 -fsyntax-only -ffreestanding -fms-extensions %s
 // expected-no-diagnostics
 
 #include <arm_acle.h>