UpdateLibunwind

#!/usr/bin/env bash
set -eu -o pipefail
cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")"

git diff --exit-code -- . ':(exclude)UpdateLibunwind' > /dev/null || { echo "Commit changes before updating!" ; exit 1 ; }

# https://github.com/llvm/llvm-project/releases
COMMIT="${1:-llvmorg-19.1.7}"

pushd vendor >/dev/null
rm -rf libunwind
mkdir -p libunwind
pushd libunwind >/dev/null
git init
git sparse-checkout set cmake libunwind llvm/cmake llvm/utils/llvm-lit runtimes
git remote add upstream "https://github.com/llvm/llvm-project"
git fetch --depth 1 upstream "refs/tags/${COMMIT}:refs/tags/${COMMIT}"
git checkout "${COMMIT}"
popd >/dev/null
popd >/dev/null

! git diff --exit-code > /dev/null || { echo "This repository is already up to date" ; exit 0 ; }

git commit -a \
  -m "Bump libunwind to \`${COMMIT}\`" \
  -m "- https://github.com/llvm/llvm-project/releases/tag/${COMMIT}"

echo "The repo has been updated with a commit recording the update."
echo "You can review the changes with 'git diff HEAD^' before pushing to a public repository."