fixup! build: add new build system

Author: VincentVanlaer

make/defaults-module.mk

@@ -2,6 +2,10 @@
 # This is not a problem, but it makes the output nicer
 MAKE_DIR := $(shell echo $(dir $(lastword $(MAKEFILE_LIST))) | sed "s|/$$||")
 
+ifneq ($(.SHELLSTATUS),0)
+  $(error extracting `make` directory based on defaults-module.mk location failed)
+endif
+
 BUILD_DIR ?= build
 COMPILER ?= gfortran
 VERSION ?= $(file <$(MAKE_DIR)../data/version_number)