diff --git a/sys/sys/imgact_elf.h b/sys/sys/imgact_elf.h
index 1023b3c829c3..960b0fa48e7d 100644
--- a/sys/sys/imgact_elf.h
+++ b/sys/sys/imgact_elf.h
@@ -39,6 +39,13 @@
 
 #define	AUXARGS_ENTRY(pos, id, val) \
     {(pos)->a_type = (id); (pos)->a_un.a_val = (val); (pos)++;}
+#if (defined(__LP64__) && __ELF_WORD_SIZE == 32)
+#define	AUXARGS_ENTRY_PTR(pos, id, ptr) \
+    {(pos)->a_type = (id); (pos)->a_un.a_val = (uintptr_t)(ptr); (pos)++;}
+#else
+#define	AUXARGS_ENTRY_PTR(pos, id, ptr) \
+    {(pos)->a_type = (id); (pos)->a_un.a_ptr = (ptr); (pos)++;}
+#endif
 
 struct image_params;
 struct thread;