🧑‍💻 Fix and improve build_all_examples

buildroot/bin/build_example

@@ -22,6 +22,15 @@ cp "$SUB"/Configuration_adv.h Marlin/ 2>/dev/null
 cp "$SUB"/_Bootscreen.h       Marlin/ 2>/dev/null
 cp "$SUB"/_Statusscreen.h     Marlin/ 2>/dev/null
 
+set -e
+
+# Strip #error lines from Configuration.h
+SED=$(which gsed sed | head -n1)
+IFS=$'\n'; set -f
+$SED -i~ -e "20,30{/#error/d}" Marlin/Configuration.h
+rm Marlin/Configuration.h~
+unset IFS; set +f
+
 echo "Building the firmware now..."
 HERE=`dirname "$0"`
 $HERE/mftest -s -a -n1 || { echo "Failed"; exit 1; }