diff -r 000000000000 -r b4b281ef2d0f make/update-rules.sh
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/make/update-rules.sh	Sat Jan 11 13:45:38 2025 +0100
@@ -0,0 +1,55 @@
+#!/bin/sh
+
+dir="$1"
+target="$2"
+extra_flags="$3"
+
+if [ -z "$dir" ]; then
+  echo "Usage: $0 <src_dir>"
+  exit 1
+fi
+
+if [ -z "$target" ]; then
+  target='../build'
+fi
+
+if [ -d "$dir" ]; then
+  :
+else
+  echo "'$dir' is not a directory"
+  exit 1
+fi
+
+if [ -z "$CXX" ]; then
+  for cxx in g++ clang++ ; do
+    if command -v "$cxx" > /dev/null ; then
+      CXX="$cxx"
+      break
+    fi
+  done
+fi
+
+if [ -z "$CXX" ]; then
+  echo "No suitable compiler found to generate make rules"
+  exit 1
+fi
+
+if command -v sed > /dev/null ; then
+  :
+else
+  echo "You need the 'sed' program for this script to work."
+  exit 1
+fi
+
+cd "$dir"
+
+mv Makefile Makefile.old
+sed '/FORCE:/q' Makefile.old > Makefile
+echo >> Makefile
+for file in `ls *.cpp` ; do
+  "$CXX" -MT "$target/${file/.cpp/\.o}" -MM $CXXFLAGS $extra_flags "$file"
+  printf '\t@echo "Compiling $<"\n'
+  printf '\t$(CXX) -o $@ $(CXXFLAGS) %s -c $<\n\n' "$extra_flags"
+done  >> Makefile
+rm Makefile.old
+