ifeq ($(shell sha512sum --version >/dev/null 2>&1 || echo FAIL),) SHA512SUM = sha512sum else ifeq ($(shell shasum --version >/dev/null 2>&1 || echo FAIL),) SHA512SUM = shasum -a 512 else ifeq ($(shell openssl version >/dev/null 2>&1 || echo FAIL),) SHA512SUM = openssl sha512 else SHA512SUM = $(error no SHA-512 tool found!) endif