.PRECIOUS 目标没有被编译，并且没有为所有人做任何事情

Question

我想要执行 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。文件没有生成，它说 nothing to do

生成文件

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

上运行使

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

Answer 1

据我所知，

.PRECIOUS 对您遇到的问题没有影响。从 make 的角度来看，您的 makefile 归结为两条规则：

all: system-check

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

就是这样。我没有看到 all 的任何其他先决条件，所以这就是它要做的。

为了从 make 中获取该消息，(a) 您的文件系统上有一个名为 all 的文件，或者 (b) 您的文件系统上有一个名为 system-check 的文件。

您可以通过运行 make -d 并检查输出来找出它是什么，and/or make 还在做什么。

您可以通过将这些特殊目标设置为 .PHONY:

来避免文件系统中存在的文件出现问题

.PHONY: all system-check

.PRECIOUS 目标没有被编译，并且没有为所有人做任何事情

.PRECIOUS target not getting compiled and says nothing to be done for all

makefile

grpc