From f9abae77a41c4f5919aca77a46f78a0e706f7e91 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 23 Jun 2026 04:28:34 +0000
Subject: [PATCH] Handle unset DISABLE_UPDATE safely in build.func

---
 misc/build.func | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/misc/build.func b/misc/build.func
index ec501e50a..d67f048e8 100644
--- a/misc/build.func
+++ b/misc/build.func
@@ -5722,7 +5722,8 @@ create_lxc_container() {
       return 0
     fi
 
-    if [[ "${PHS_SILENT:-0}" == "1" || "${DISABLE_UPDATE:-}" =~ ^([Yy][Ee][Ss])$ ]]; then
+    local _disable_update="${DISABLE_UPDATE:-}"
+    if [[ "${PHS_SILENT:-0}" == "1" || "${_disable_update,,}" == "yes" ]]; then
       msg_info "Skipping host LXC stack upgrade prompt (unattended mode)"
       return 2
     fi