src/boot/efi/no-undefined-symbols.sh - systemd - Git at Google

 #!/bin/bash
 # SPDX-License-Identifier: LGPL-2.1-or-later
 set -eu
 set -o pipefail

 if nm -D -u "${1:?}" | grep ' U '; then
     echo "Undefined symbols detected!"
     exit 1
 fi
	#!/bin/bash
	# SPDX-License-Identifier: LGPL-2.1-or-later
	set -eu
	set -o pipefail

	if nm -D -u "${1:?}" \| grep ' U '; then
	echo "Undefined symbols detected!"
	exit 1
	fi