diff --git a/include/xen/arm/interface.h b/include/xen/arm/interface.h
index c3eada2642aa..61360b89da40 100644
--- a/include/xen/arm/interface.h
+++ b/include/xen/arm/interface.h
@@ -30,7 +30,7 @@
 
 #define __HYPERVISOR_platform_op_raw __HYPERVISOR_platform_op
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 /* Explicitly size integers that represent pfns in the interface with
  * Xen so that we can have one ABI that works for 32 and 64 bit guests.
  * Note that this means that the xen_pfn_t type may be capable of