Nix/mk/precompiled-headers.mk
Eelco Dolstra 5ff4d77f55
Precompile headers
This cuts 'make install -j6' on my laptop from 170s to 134s.
2019-11-07 10:12:35 +01:00

43 lines
926 B
Makefile

PRECOMPILE_HEADERS ?= 1
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)
PCH = $(buildprefix)precompiled-headers.h.pch
$(PCH): precompiled-headers.h
@rm -f $@
@mkdir -p "$(dir $@)"
$(trace-gen) $(CXX) -x c++-header -o $@ $^ $(GLOBAL_CXXFLAGS)
clean-files += $(GCH) $(PCH)
ifeq ($(PRECOMPILE_HEADERS), 1)
ifeq ($(CXX), g++)
GLOBAL_CXXFLAGS_PCH += -include $(buildprefix)precompiled-headers.h -Winvalid-pch
GLOBAL_ORDER_AFTER += $(GCH)
else ifeq ($(CXX), clang++)
GLOBAL_CXXFLAGS_PCH += -include-pch $(PCH) -Winvalid-pch
GLOBAL_ORDER_AFTER += $(PCH)
else
$(error Don't know how to precompile headers on $(CXX))
endif
endif