diff --git a/src/lj_mcode.c b/src/lj_mcode.c
index 3eaee054..de785a09 100644
--- a/src/lj_mcode.c
+++ b/src/lj_mcode.c
@@ -206,6 +206,9 @@ static void mcode_protect(jit_State *J, int prot)
 
 #if LJ_TARGET_X64
 #define mcode_validptr(p)	((p) && (uintptr_t)(p) < (uintptr_t)1<<47)
+#elif LJ_TARGET_ARM64
+/* We have no clue about the valid VA range. It could be 39 - 52 bits. */
+#define mcode_validptr(p)	(p)
 #else
 #define mcode_validptr(p)	((p) && (uintptr_t)(p) < 0xffff0000)
 #endif