diff --git a/xen/arch/x86/include/asm/alternative-call.h b/xen/arch/x86/include/asm/alternative-call.h
index 27024797f5..809023bc4d 100644
--- a/xen/arch/x86/include/asm/alternative-call.h
+++ b/xen/arch/x86/include/asm/alternative-call.h
@@ -9,7 +9,7 @@
 struct alt_call {
     int32_t offset;
 };
-#define ALT_CALL_PTR(a) ((void *)&(a)->offset + (a)->offset)
+#define ALT_CALL_PTR(a) ((void *)((long)&(a)->offset + (a)->offset))
 #define ALT_CALL_LEN(a) (6)
 
 /*