From a872fe877356b62e7d859d8674d8dd9bb4c697a8 Mon Sep 17 00:00:00 2001
From: Ricardo Pardini <ricardo@pardini.net>
Date: Sun, 7 May 2023 15:52:10 +0200
Subject: [PATCH] config-prepare: `config_pre_main()`: try to be more helpful
 when BRANCH is unset or wrong instead of just "bad KERNEL_MAJOR_MINOR"

---
 lib/functions/main/config-prepare.sh | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/functions/main/config-prepare.sh b/lib/functions/main/config-prepare.sh
index 467bd6e1e6..85c44ca328 100644
--- a/lib/functions/main/config-prepare.sh
+++ b/lib/functions/main/config-prepare.sh
@@ -214,7 +214,17 @@ function config_post_main() {
 	if [[ "${skip_kernel:-"no"}" != "yes" ]]; then
 		if [[ -n "${KERNELSOURCE}" ]]; then
 			if [[ "x${KERNEL_MAJOR_MINOR}x" == "xx" ]]; then
-				exit_with_error "BAD config, missing" "KERNEL_MAJOR_MINOR" "err"
+				display_alert "Problem: after configuration, there's not enough kernel info" "Might happen if you used the wrong BRANCH. Make sure 'BRANCH=${BRANCH}' is valid." "err"
+				# if we have KERNEL_TARGET set.
+				if [[ -n "${KERNEL_TARGET}" ]]; then
+					# Split KERNEL_TARGET by commas, and display each one.
+					declare -a KERNEL_TARGET_ARRAY=()
+					IFS=',' read -ra KERNEL_TARGET_ARRAY <<< "${KERNEL_TARGET}"
+					for i in "${KERNEL_TARGET_ARRAY[@]}"; do
+						display_alert "Valid branches for current board" "BOARD=${BOARD} BRANCH=${i}" "info"
+					done
+				fi
+				exit_with_error "BAD config, missing" "KERNEL_MAJOR_MINOR; check BOARD and BRANCH combination" "err"
 			fi
 			# assume the worst, and all surprises will be happy ones
 			declare -g KERNEL_HAS_WORKING_HEADERS="no"