diff --git a/adapt-to-upstream-toolchains.sh b/adapt-to-upstream-toolchains.sh
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+#!/bin/bash
+
+# Purpose:
+# Linux kernel upstream may change properties of build toolchains over the years.
+# MARS is currently downstream and/or out-of-tree.
+# Here we adapt ourselves to the kernel upstream.
+# This method should also ease the removal of legacy code from MARS,
+# as far as possible, when combined with some old kernels.
+# Hopefully, this can help in becoming upstream.
+#
+# We make some reorg git commits.
+# In order to ease "git rebase" and siblings, we make separate
+# commits for renames vs resurrections.
+# Resurrections are needed for compatibility with old kernels
+# and their old toolchains, when combined with old MARS versions.
+#
+# Our own previous intermediate versions are retained by default.
+#
+# Checking the resulting commits, and appending more commits is up to you.
+# When nothing will actually change, you can remove some of the (intermediate) commits.
+#
+# Adaptations of any pre-patches to newer kernels is also up to you.
+
+echo -n "Enter new version string with numbers (like 5.4) or press Ctrl-C: "
+read new_version
+
+shopt -s nullglob
+
+function cmp_version
+{
+    local a="$1"
+    local b="$2"
+
+    if (( ${a%%.*} < ${b%%.*} )); then
+	echo "-1"
+    elif (( ${a%%.*} > ${b%%.*} )); then
+	echo "1"
+    elif [[ "$a" =~ \. ]] && [[ "$b" =~ \. ]]; then
+	local a_short="$(echo "$a" | sed 's/^[0-9]*\.//')"
+	local b_short="$(echo "$b" | sed 's/^[0-9]*\.//')"
+	cmp_version "$a_short" "$b_short"
+    elif [[ "$a" =~ \. ]]; then
+	# only descend the version hierarchy of a
+	local a_short="$(echo "$a" | sed 's/^[0-9]*\.//')"
+	cmp_version "$a_short" "0"
+    elif [[ "$b" =~ \. ]]; then
+	# only descend the version hierarchy of b
+	local b_short="$(echo "$b" | sed 's/^[0-9]*\.//')"
+	cmp_version "0" "$b_short"
+    else
+	# no descend possible: treat as equal
+	echo "0"
+    fi
+}
+
+function adapt_file
+{
+    # parameters
+    local old_filename="$1"
+    local new_version="${2:-$new_version}"
+
+    # derivatives
+    local script="$(basename $0)"
+    local txt="toolchains"
+    local dirname="$(dirname $old_filename)"
+    local new_filename="$dirname/$(basename $old_filename | sed 's/\.v[^.]*$//').v$new_version"
+
+    # filter any intermediate versions
+    local med_filename="$old_filename"
+    local old_version=""
+    local this_version=""
+    local i
+    for i in $old_filename $old_filename.v*; do
+	if ! [[ -s "$i" ]]; then
+	    continue
+	fi
+
+	this_version="$(echo "$i" | grep -o "[0-9.]*$")"
+	if [[ "$this_version" = "" ]]; then
+	    continue
+	fi
+
+	# ignore out-of-bounds versions
+	local cond_A=0
+	if [[ "$old_version" = "" ]] || (( $(cmp_version "$old_version" "$this_version") <= 0 )); then
+	    (( cond_A++ ))
+	fi
+	local cond_B=0
+	if [[ "$new_version" = "" ]] || (( $(cmp_version "$this_version" "$new_version") <= 0 )); then
+	    (( cond_B++ ))
+	fi
+	if (( !cond_A || !cond_B )); then
+	    continue
+	fi
+
+	# remember any better matching versions
+	old_version=$this_version
+	med_filename="$i"
+    done
+
+    echo "TRANSFER $med_filename -> $new_filename"
+
+    # checks
+    if [[ "$new_filename" = "$med_filename" ]]; then
+	echo "Sorry, no change in filename."
+	exit 1
+    fi
+
+    # Step 1: rename the old file to the new one
+    echo git mv $med_filename $new_filename
+    git mv $med_filename $new_filename || exit $?
+    echo "git commit -m \"$txt: git mv $med_filename -> $new_filename\""
+    git commit --no-interactive -m "$txt: git mv $med_filename -> $new_filename" || exit $?
+
+    # Step 2: resurrect the old file and content
+    echo cp -a $new_filename $med_filename
+    cp -a $new_filename $med_filename || exit $?
+    echo git add $med_filename
+    git add $med_filename || exit $?
+    echo "git commit -m \"$txt: resurrect $med_filename\""
+    git commit --no-interactive -m "$txt: resurrect $med_filename" || exit $?
+
+    echo "SUCCESS $med_filename -> $new_filename"
+}
+
+git reset || exit $?
+git checkout . || exit $?
+
+# Current upstream dependencies of files.
+# May change in future.
+
+adapt_file kernel/Kconfig
+adapt_file kernel/Kbuild