Makefile .宝贵的目标没有得到编译，并且说什么都不需要做

我希望执行

Makefile

中的以下目标

.PRECIOUS

，以便根据

.proto

文件生成适当的gRPC头源文件。文件未生成，它显示

无事可做

Makefile

HOST_SYSTEM = $(shell uname | cut -f 1 -d_)
SYSTEM ?= $(HOST_SYSTEM)
CXX = g++
CPPFLAGS += `pkg-config --cflags protobuf grpc`
CXXFLAGS += -std=c++11
ifeq ($(SYSTEM),Darwin)
LDFLAGS += -L/usr/local/lib `pkg-config --libs protobuf grpc++ grpc`\
           -lgrpc++_reflection\
           -ldl
else
LDFLAGS += -L/usr/local/lib `pkg-config --libs protobuf grpc++ grpc`\
           -Wl,--no-as-needed -lgrpc++_reflection -Wl,--as-needed\
           -ldl
endif
PROTOC = protoc
GRPC_CPP_PLUGIN = grpc_cpp_plugin
GRPC_CPP_PLUGIN_PATH ?= `which $(GRPC_CPP_PLUGIN)`

PROTOS_PATH = protos

vpath %.proto $(PROTOS_PATH)


all: system-check

.PRECIOUS: %.grpc.pb.cc
%.grpc.pb.cc: %.proto
        $(PROTOC) -I $(PROTOS_PATH) --grpc_out=. --plugin=protoc-gen-grpc=$(GRPC_CPP_PLUGIN_PATH) $<

.PRECIOUS: %.pb.cc
%.pb.cc: %.proto
        $(PROTOC) -I $(PROTOS_PATH) --cpp_out=. $<


clean:
        rm -f *.o *.pb.cc *.pb.h


# The following is to test your system and ensure a smoother experience.
# They are by no means necessary to actually compile a grpc-enabled software.

PROTOC_CMD = which $(PROTOC)
PROTOC_CHECK_CMD = $(PROTOC) --version | grep -q libprotoc.3
PLUGIN_CHECK_CMD = which $(GRPC_CPP_PLUGIN)
HAS_PROTOC = $(shell $(PROTOC_CMD) > /dev/null && echo true || echo false)
ifeq ($(HAS_PROTOC),true)
HAS_VALID_PROTOC = $(shell $(PROTOC_CHECK_CMD) 2> /dev/null && echo true || echo false)
endif
HAS_PLUGIN = $(shell $(PLUGIN_CHECK_CMD) > /dev/null && echo true || echo false)

SYSTEM_OK = false
ifeq ($(HAS_VALID_PROTOC),true)
ifeq ($(HAS_PLUGIN),true)
SYSTEM_OK = true
endif
endif

system-check:

ifneq ($(HAS_VALID_PROTOC),true)
        @echo " DEPENDENCY ERROR"
        @echo
        @echo "You don't have protoc 3.0.0 installed in your path."
        @echo "Please install Google protocol buffers 3.0.0 and its compiler."
        @echo "You can find it here:"
        @echo
        @echo "   https://github.com/google/protobuf/releases/tag/v3.0.0"
        @echo
        @echo "Here is what I get when trying to evaluate your version of protoc:"
        @echo
        -$(PROTOC) --version
        @echo
        @echo
endif
ifneq ($(HAS_PLUGIN),true)
        @echo " DEPENDENCY ERROR"
        @echo
        @echo "You don't have the grpc c++ protobuf plugin installed in your path."
        @echo "Please install grpc. You can find it here:"
        @echo
        @echo "   https://github.com/grpc/grpc"
        @echo
        @echo "Here is what I get when trying to detect if you have the plugin:"
        @echo
        -which $(GRPC_CPP_PLUGIN)
        @echo
        @echo
endif
ifneq ($(SYSTEM_OK),true)
        @false
endif

Bob@hub:~/Raju/demo_grpc$ make
make: Nothing to be done for 'all'.

---

据我所知，

.PRECIOUS

对您看到的问题没有影响。从make的角度来看，您的makefile可以归结为两条规则：

all: system-check

system-check:
        ...some echo lines or exit 1...

就这样。我看不到

all

的任何其他先决条件，所以它只能满足这些要求

为了从make获取该消息，可以（a）文件系统中有一个名为

all

的文件，或者（b）文件系统中有一个名为

system check

的文件

通过运行

make-d

并检查输出，您可以找出它是什么，和/或make正在做什么

您可以通过使文件系统中的文件成为

，避免这些特殊目标的文件出现问题。虚假的
：

.PHONY: all system-check