PRECOMPILE_HEADERS ?= 0

print-var-help += \
  echo "  PRECOMPILE_HEADERS ($(PRECOMPILE_HEADERS)): Whether to use precompiled headers to speed up the build";

GCH = $(buildprefix)precompiled-headers.h.gch

$(GCH): precompiled-headers.h
	@rm -f $@
	@mkdir -p "$(dir $@)"
	$(trace-gen) $(CXX) -x c++-header -o $@ $< $(GLOBAL_CXXFLAGS) $(GCH_CXXFLAGS)

clean-files += $(GCH)

ifeq ($(PRECOMPILE_HEADERS), 1)

  GLOBAL_CXXFLAGS_PCH += -include $(buildprefix)precompiled-headers.h -Winvalid-pch

  GLOBAL_ORDER_AFTER += $(GCH)

endif