From 57fc055665d2fdf6dcf22c62472126c8ad597474 Mon Sep 17 00:00:00 2001
From: MengHeng <mengheng@MacBookPro.lan>
Date: Fri, 6 Feb 2026 10:41:13 +0700
Subject: [PATCH] maint: add a comment to help point to a solution when docker
 build on macOS

---
 _common/builder.inc.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/_common/builder.inc.sh b/_common/builder.inc.sh
index c899383..2e0aa02 100644
--- a/_common/builder.inc.sh
+++ b/_common/builder.inc.sh
@@ -2300,6 +2300,7 @@ builder_is_linux() {
 #
 _builder_get_operating_system() {
   declare -g BUILDER_OS
+  # Note: on macOS, bash version 4 or above is needed for `declare -g`.
 
   if builder_is_macos; then
     BUILDER_OS=mac