无法链接libFuzzer.a使用clang与libc++

Question

我想把它们联系起来：

• libFuzzer.a，用clang++-5.0和-std=c++11编译
• 我的模糊驱动程序，用clang++-5.0和-std=c++11 -stdlib=libc++编译
• libcurl，用clang-5.0编译

具体来说，正在执行这个链接器命令：

/bin/bash ././libtool静默-标记=CXX-模式=链接clang++-5.0 -i././包含-i./../lib-i./lib-i././test/fuzz -fsanitize=address -fsanitize-使用-范围后-fsanitize-覆盖率=跟踪-pc保护，跟踪-cmp -std=c++11 -stdlib=libc++ -o curl_fuzzer curl_fuzzer-curl_fuzzer.o ./lib/libcurl.la/root/checkout/Fuzzer/libFuzzer.a.a -lssh2 -lssl -lcrypto -lssl -lcrypto -lz -lpthread -lm

执行此命令将输出以下内容：

/bin/bash ../../libtool --silent --tag=CXX   --mode=link clang++-5.0 -I../../include -I../../lib -I../../lib -I../../tests/fuzz -fsanitize=address -fsanitize-address-use-after-scope -fsanitize-coverage=trace-pc-guard,trace-cmp -std=c++11 -stdlib=libc++   -o curl_fuzzer curl_fuzzer-curl_fuzzer.o ../../lib/libcurl.la /root/checkouts/Fuzzer/libFuzzer.a  -lssh2 -lssl -lcrypto -lssl -lcrypto -lz -lpthread -lm > /tmp/cat.txt 2>&1; head -20 /tmp/cat.txt
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `fuzzer::FileToVector(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned long, bool)':
/root/checkouts/Fuzzer/./FuzzerIO.cpp:34: undefined reference to `std::basic_ifstream<char, std::char_traits<char> >::basic_ifstream(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::_Ios_Openmode)'
/root/checkouts/Fuzzer/./FuzzerIO.cpp:40: undefined reference to `std::istream::seekg(long, std::_Ios_Seekdir)'
/root/checkouts/Fuzzer/./FuzzerIO.cpp:41: undefined reference to `std::istream::tellg()'
/root/checkouts/Fuzzer/./FuzzerIO.cpp:47: undefined reference to `std::istream::seekg(long, std::_Ios_Seekdir)'
/root/checkouts/Fuzzer/./FuzzerIO.cpp:49: undefined reference to `std::istream::read(char*, long)'
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `~basic_ifstream':
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/fstream:534: undefined reference to `VTT for std::basic_ifstream<char, std::char_traits<char> >'
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/fstream:534: undefined reference to `std::basic_ifstream<char, std::char_traits<char> >::~basic_ifstream()'
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `~basic_ios':
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/bits/basic_ios.h:282: undefined reference to `std::ios_base::~ios_base()'
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `~basic_ifstream':
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/fstream:534: undefined reference to `VTT for std::basic_ifstream<char, std::char_traits<char> >'
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/fstream:534: undefined reference to `std::basic_ifstream<char, std::char_traits<char> >::~basic_ifstream()'
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `~basic_ios':
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/bits/basic_ios.h:282: undefined reference to `std::ios_base::~ios_base()'
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `fuzzer::FileToString(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
/root/checkouts/Fuzzer/./FuzzerIO.cpp:54: undefined reference to `std::basic_ifstream<char, std::char_traits<char> >::basic_ifstream(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::_Ios_Openmode)'
/root/checkouts/Fuzzer/libFuzzer.a(FuzzerIO.o): In function `~basic_ifstream':
/usr/bin/../lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/fstream:534: undefined reference to `VTT for std::basic_ifstream<char, std::char_traits<char> >'
<snip>

我试着做了以下工作来解决这个问题：

• 添加-lc++ -什么都不做
• 添加-lc++abi -什么都不做

感觉好像我错过了一些显而易见的东西但我不知道是什么..。

我的clang-5.0安装来自clang-5.0/kali-rolling。

Answer 1

您已经用libstdc++编译了部分代码，用libc++编译了部分代码。当您将它们链接在一起(使用libc++)时，具有对libstdc++的引用的部分不会被解析。

例如，std::__cxx11::basic_string绝对是一个libstdc++符号。

Answer 2

看起来，不管出于什么原因，kali的clang-5.0版本没有正确地将二进制文件与libc++连接起来。我用google的ossfuzz版本的clang (clang-6.0)测试了相同的代码，并成功地将所有内容链接在一起。