message: guix: Make V=1 more powerful for debugging
  Print commands in both unexpanded and expanded forms
  Set VERBOSE=1 for CMake
diff: @@ -3,6 +3,14 @@ export LC_ALL=C
  set -e -o pipefail
  export TZ=UTC
  +if [ -n "$V" ]; then
  + # Print both unexpanded (-v) and expanded (-x) forms of commands as they are
  + # read from this file.
  + set -vx
  + # Set VERBOSE for CMake-based builds
  + export VERBOSE="$V"
  +fi
  +
  # Check that environment variables assumed to be set by the environment are set
  echo "Building for platform triple ${HOST:?not set} with reference timestamp ${SOURCE_DATE_EPOCH:?not set}..."
  echo "At most ${MAX_JOBS:?not set} jobs will run at once..."
  