Forward Makefile to subdirectory `build`

Makefile

# List targets defined in this file
TARGETS_SELF := cmake
# Exclude targets defined in this file
TARGETS_OTHER := $(filter-out $(TARGETS_SELF), $(MAKECMDGOALS))

# Call all targets using `Makefile` in build directory in one `make` command. It
# can depend on targets defined in this file, e.g., depending on a target to
# create the Makefile.
#
# If no targets are specified, use the dummy `all` target
$(or $(lastword $(TARGETS_OTHER)),all):
	$(MAKE) -C build $(TARGETS_OTHER)
.PHONY: $(TARGETS_OTHER) all

# Do nothing for all targets but last. Also quiet the message "Noting to be done on xxx"
$(filter-out $(lastword $(TARGETS_OTHER)), $(TARGETS_OTHER)):
	@cd .

cmake:
	cd build && cmake ../src

.PHONY: cmake

Say your Makefile is in build, but you want to call make in top directory without specifying -C

Very useful, thanks! Unfortunately it relies on GNU make features. Do you happen to know a version that achieves the same thing with BSD make?