diff --git a/sdk_container/src/third_party/portage-stable/eclass/waf-utils.eclass b/sdk_container/src/third_party/portage-stable/eclass/waf-utils.eclass
index f8d4b0aa94..377b455de7 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/waf-utils.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/waf-utils.eclass
@@ -1,4 +1,4 @@
-# Copyright 1999-2023 Gentoo Authors
+# Copyright 1999-2024 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 # @ECLASS: waf-utils.eclass
@@ -20,7 +20,7 @@ case ${EAPI} in
 	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
 esac
 
-if [[ ! ${_WAF_UTILS_ECLASS} ]]; then
+if [[ -z ${_WAF_UTILS_ECLASS} ]]; then
 _WAF_UTILS_ECLASS=1
 
 inherit multilib toolchain-funcs multiprocessing