diff --git a/include/allegro5/internal/aintern_atomicops.h b/include/allegro5/internal/aintern_atomicops.h
index 5054552..a4310f1 100644
--- a/include/allegro5/internal/aintern_atomicops.h
+++ b/include/allegro5/internal/aintern_atomicops.h
@@ -49,7 +49,7 @@
       return old - 1;
    })
 
-#elif defined(_MSC_VER) && _M_IX86 >= 400
+#elif defined(_MSC_VER) && (_M_IX86 >= 400 || defined(_M_ARM64))
 
    /* MSVC, x86 */
    /* MinGW supports these too, but we already have asm code above. */