diff --git a/src/btf.h b/src/btf.h
index 3b0b17b..b54f1c3 100644
--- a/src/btf.h
+++ b/src/btf.h
@@ -176,6 +176,7 @@ struct btf_dump_emit_type_decl_opts {
 	int indent_level;
 	/* strip all the const/volatile/restrict mods */
 	bool strip_mods;
+	size_t :0;
 };
 #define btf_dump_emit_type_decl_opts__last_field strip_mods