diff --git a/openmp/runtime/src/kmp_atomic.cpp b/openmp/runtime/src/kmp_atomic.cpp
--- a/openmp/runtime/src/kmp_atomic.cpp
+++ b/openmp/runtime/src/kmp_atomic.cpp
@@ -3694,6 +3694,8 @@
   __kmp_release_atomic_lock(&__kmp_atomic_lock, gtid);
 }
 
+#if KMP_ARCH_X86 || KMP_ARCH_X86_64
+
 // OpenMP 5.1 compare and swap
 
 /*!
@@ -3855,6 +3857,7 @@
 }
 
 // End OpenMP 5.1 compare + capture
+#endif // KMP_ARCH_X86 || KMP_ARCH_X86_64
 
 /*!
 @}