.PHONY: report.main report.gcc report.modules report.var report.true report.help
.PHONY: shell.run

report.modules::

report.main:
	@$(MAKE) report.true REPORT=main

report.gcc:
	@$(MAKE) report.true REPORT=gcc

report.var:
	@$(MAKE) report.true REPORT=var

## needed for nested make (which drives each report)
report.true:
	@true

## linefeed is important
define REPORT.help.item.global
	@echo 'report.$(1)' | awk '{ printf("  %-21s  $(REPORT.help.$(1))\n", $$0) }'

endef
define REPORT.help.item.module
	@echo '$($(1).name).report' | awk '{ printf("  %-21s  $(1)-scoped vars\n", $$0) }'

endef

REPORT.help.main = global general vars
REPORT.help.gcc  = global gcc vars (inherited by module GCC)
REPORT.help.var  = usage: make report.var name=VARNAME

report.help:
	@echo "  AVAILABLE MAKEFILE VARS REPORTS"
	@echo "  ----------------------------------------------------------------"
	$(foreach n,main gcc var,$(call REPORT.help.item.global,$n))
	$(foreach n,$(MODULES.NAMES),$(call REPORT.help.item.module,$n))

## diagnostic aid when troubleshooting build issues
shell.run:
	$(command)
