c++ - 如何创建 makefile 构建 Snappy 作为静态库

Question

我有构建 snappy 库所需的文件:

• snappy.h
• snappy.cc
• snappy-c.h
• snappy-c.cc
• snappy-internal.h
• snappy-sinksource.h
• snappy-sinksource..cc
• snappy-stubs-internal.h
• snappy-stubs-internal.cc
• snappy-stubs-public.h
• snappy-test.h
• snappy-test.cc
• snappy-unittest.cc

如何创建 makefile 将 Snappy 作为静态库。

我现在知道我必须从每个 .cpp 文件创建 .o 文件，因此我有可变且最重要的规则。

OBJS=snappy.o snappy-c.o snappy-sinksource.o snappy-stubs-internal.o\
snappy-test.o snappy_unittest.o
CC=gcc
CCFLAGS=-Wall -static

$(OBJS): %.o:%.cc
    $(CC) $(CCFLAGS) $< -o $@
clean:
-rm -rf *.o
.PHONY: clean

接下来我要做什么？

[编辑]: 我现在有:

OBJS=snappy.o snappy-c.o snappy-sinksource.o snappy-stubs-internal.o snappy-test.o snappy_unittest.o
CC=gcc
CCFLAGS=-Wall -static
LIBNAME=libsnappy.a

all:$(LIBNAME)

$(LIBNAME): $(OBJS)
    ar rcs $@ $^
$(OBJS): %.o:%.cc
    $(CC) $(CCFLAGS) $< -o $@
clean:
    -rm -rf *.o
.PHONY: clean

但仍然不起作用:

gcc -Wall -static snappy.cc -o snappy.o
snappy.cc: In member function ‘bool snappy::SnappyIOVecWriter::Append(const char*, size_t)’:
snappy.cc:1013:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (curr_iov_index_ + 1 >= output_iov_count_) {
                                    ^
snappy.cc: In member function ‘bool snappy::SnappyIOVecWriter::AppendFromSelf(size_t, size_t)’:
snappy.cc:1095:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
           if (curr_iov_index_ + 1 >= output_iov_count_) {
                                      ^
snappy.cc: At global scope:
snappy.cc:567:13: warning: ‘void snappy::ComputeTable()’ defined but not used [-Wunused-function]
 static void ComputeTable() {
             ^
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 0 has invalid symbol index 11
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 1 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 2 has invalid symbol index 2
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 3 has invalid symbol index 2
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 4 has invalid symbol index 11
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 5 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 6 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 7 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 8 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 9 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 10 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 11 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 12 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 13 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 14 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 15 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 16 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 17 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 18 has invalid symbol index 13
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 19 has invalid symbol index 21
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_line): relocation 0 has invalid symbol index 2
/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/crt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
/tmp/ccTyhFNH.o: In function `snappy::internal::WorkingMemory::GetHashTable(unsigned long, int*)':
snappy.cc:(.text+0x5f9): undefined reference to `operator new[](unsigned long)'
/tmp/ccTyhFNH.o: In function `snappy::Compress(snappy::Source*, snappy::Sink*)':
snappy.cc:(.text+0x1608): undefined reference to `operator new[](unsigned long)'
snappy.cc:(.text+0x17ff): undefined reference to `operator new[](unsigned long)'
snappy.cc:(.text+0x1926): undefined reference to `operator delete[](void*)'
snappy.cc:(.text+0x193f): undefined reference to `operator delete[](void*)'
/tmp/ccTyhFNH.o: In function `snappy::RawUncompressToIOVec(char const*, unsigned long, snappy::iovec const*, unsigned long)':
snappy.cc:(.text+0x19ec): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
snappy.cc:(.text+0x19ff): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
/tmp/ccTyhFNH.o: In function `snappy::RawUncompress(char const*, unsigned long, char*)':
snappy.cc:(.text+0x1aaa): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
snappy.cc:(.text+0x1abd): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
/tmp/ccTyhFNH.o: In function `snappy::Uncompress(char const*, unsigned long, std::string*)':
snappy.cc:(.text+0x1b58): undefined reference to `std::string::max_size() const'
/tmp/ccTyhFNH.o: In function `snappy::IsValidCompressedBuffer(char const*, unsigned long)':
snappy.cc:(.text+0x1c03): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
snappy.cc:(.text+0x1c16): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
/tmp/ccTyhFNH.o: In function `snappy::RawCompress(char const*, unsigned long, char*, unsigned long*)':
snappy.cc:(.text+0x1caf): undefined reference to `snappy::UncheckedByteArraySink::~UncheckedByteArraySink()'
snappy.cc:(.text+0x1cbb): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
snappy.cc:(.text+0x1ccc): undefined reference to `snappy::UncheckedByteArraySink::~UncheckedByteArraySink()'
snappy.cc:(.text+0x1cdd): undefined reference to `snappy::ByteArraySource::~ByteArraySource()'
/tmp/ccTyhFNH.o: In function `snappy::Compress(char const*, unsigned long, std::string*)':
snappy.cc:(.text+0x1d23): undefined reference to `std::string::resize(unsigned long)'
snappy.cc:(.text+0x1d59): undefined reference to `std::string::resize(unsigned long)'
/tmp/ccTyhFNH.o: In function `snappy::STLStringResizeUninitialized(std::string*, unsigned long)':
snappy.cc:(.text._ZN6snappy28STLStringResizeUninitializedEPSsm[_ZN6snappy28STLStringResizeUninitializedEPSsm]+0x1f): undefined reference to `std::string::resize(unsigned long)'
/tmp/ccTyhFNH.o: In function `snappy::string_as_array(std::string*)':
snappy.cc:(.text._ZN6snappy15string_as_arrayEPSs[_ZN6snappy15string_as_arrayEPSs]+0x15): undefined reference to `std::string::empty() const'
snappy.cc:(.text._ZN6snappy15string_as_arrayEPSs[_ZN6snappy15string_as_arrayEPSs]+0x31): undefined reference to `std::string::begin()'
/tmp/ccTyhFNH.o: In function `snappy::internal::WorkingMemory::~WorkingMemory()':
snappy.cc:(.text._ZN6snappy8internal13WorkingMemoryD2Ev[_ZN6snappy8internal13WorkingMemoryD5Ev]+0x2b): undefined reference to `operator delete[](void*)'
/tmp/ccTyhFNH.o: In function `snappy::Sink::Sink()':
snappy.cc:(.text._ZN6snappy4SinkC2Ev[_ZN6snappy4SinkC5Ev]+0xf): undefined reference to `vtable for snappy::Sink'
/tmp/ccTyhFNH.o: In function `snappy::Source::Source()':
snappy.cc:(.text._ZN6snappy6SourceC2Ev[_ZN6snappy6SourceC5Ev]+0xf): undefined reference to `vtable for snappy::Source'
/tmp/ccTyhFNH.o: In function `snappy::ByteArraySource::ByteArraySource(char const*, unsigned long)':
snappy.cc:(.text._ZN6snappy15ByteArraySourceC2EPKcm[_ZN6snappy15ByteArraySourceC5EPKcm]+0x27): undefined reference to `vtable for snappy::ByteArraySource'
/tmp/ccTyhFNH.o: In function `snappy::UncheckedByteArraySink::UncheckedByteArraySink(char*)':
snappy.cc:(.text._ZN6snappy22UncheckedByteArraySinkC2EPc[_ZN6snappy22UncheckedByteArraySinkC5EPc]+0x23): undefined reference to `vtable for snappy::UncheckedByteArraySink'
/tmp/ccTyhFNH.o:(.eh_frame+0x1ab): undefined reference to `__gxx_personality_v0'
collect2: error: ld returned 1 exit status
make: *** [snappy.o] Error 1

[编辑2]: 我的文件具有以下内容(并且现在正在运行):

OBJS=snappy.o snappy-c.o snappy-sinksource.o snappy-stubs-internal.o
CC=gcc
CCFLAGS=-Wall
LIBNAME=libsnappy.a
all: $(LIBNAME)
$(LIBNAME): $(OBJS)
    ar rcs $@ $^
    ranlib $@
$(OBJS): %.o:%.cc
    $(CC) $(CCFLAGS) $< -c -o $@
clean:
    -rm -rf *.o
.PHONY: clean

Answer 1

你的规则是编译并链接每个源文件，这是完全错误的，你只需要编译它。

$(OBJS): %.o:%.cc
    $(CC) $(CCFLAGS) $< -o $@

里面需要一个-c

$(OBJS): %.o:%.cc
    $(CC) $(CCFLAGS) $< -c -o $@

-static 标志不应位于 CCFLAGS 中，这是用于链接阶段的(静态库在创建静态库时不会被链接)。

CCFLAGS=-Wall