diff -r b5128bb44459 -r e59b76889f00 make/update-rules.sh
--- a/make/update-rules.sh	Mon Dec 18 18:54:17 2023 +0100
+++ b/make/update-rules.sh	Wed Dec 20 16:46:14 2023 +0100
@@ -1,12 +1,17 @@
 #!/bin/sh
 
 dir="$1"
+target="$2"
 
 if [ -z "$dir" ]; then
   echo "Usage: $0 <src_dir>"
   exit 1
 fi
 
+if [ -z "$target" ]; then
+  target='$(build_dir)'
+fi
+
 if [ -d "$dir" ]; then
   :
 else
@@ -41,7 +46,7 @@
 sed '/FORCE:/q' Makefile.old > Makefile
 echo >> Makefile
 for file in `ls *.c` ; do
-  "$CC" -MT "\$(build_dir)/${file/.c/\$(OBJ_EXT)}" -MM $CFLAGS "$file"
+  "$CC" -MT "$target/${file/.c/\$(OBJ_EXT)}" -MM $CFLAGS "$file"
   printf '\t@echo "Compiling $<"\n'
   printf '\t$(CC) -o $@ $(CFLAGS) -c $<\n\n'
 done  >> Makefile