ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
  ifeq ("$(origin V)", "command line")
    KBUILD_VERBOSE = $(V)
  endif
endif

#ifeq ($(MAKELEVEL),0)
ifndef TRACE
  TRACE:=3>&1 4>&2
endif

ifeq ($(MAKELEVEL),$(KBUILD_VERBOSE))
  TRACE+=3>/dev/null &>/dev/null
endif

define make 
@{  \
  echo "  MAKE $(1) [$(MAKEFLAGS)]" >&3; \
  TRACE_PATH="make[$$(($(MAKELEVEL)+1))]: $(1)\\n$(TRACE_PATH)"; \
  $(MAKE) TRACE_PATH="$$TRACE_PATH" --no-print-dir $(1) 2>&4 || \
    echo -e "$$TRACE_PATH" >&4; \
} $(TRACE)
endef

#.NOTPARALLEL: parallel-1

#simple test
all:
	+$(call make, -j 2 parallel-1)

parallel-1: a0 a1 a2 a3 a3 a5 a6 a7 a8 a9
parallel-2: b0 b1 b2 b3 b4 b5 b6 b7 b8 b9

%: $@
	@sleep 2
	@echo "make[$$(($(MAKELEVEL)+1))] -> $*"


a5:
	@echo "forcing -j3"
	+$(call make,-j 3 parallel-2)

a9:
	$(error foo)

a0:
	@echo "=a0="

a1:
	@echo "=a1="

.PHONY: %