Question

我正在尝试编译使用std :: filesystem的应用程序。我正在使用CMake作为构建系统，并使用g ++-8作为编译器。

我的CMakeLists.txt包含target_link_libraries(<target_name> PUBLIC stdc++fs)和set(CMAKE_CXX_STANDARD 17)

make VERBOSE=1显示链接器命令中使用了-lstdc++fs。

尽管如此，在所有使用std :: filesystem组件的地方我都得到了未定义的引用。

它在Docker中可以正常编译，因此显然是环境问题。

有什么技巧可以追踪到这个吗？

编辑：由于公司规定，我无法发布确切的错误消息，而且它也很长。我将发布一个截断的匿名版本：

CMakeFiles/ProjectName.dir/src/ui/dir_a/file_a.cpp.o: In function `ProjectName::ClassName::update(ProjectName::Body&)':
/home/username/prog/bots/src/ui/dir_a/file_a.cpp:30: undefined reference to `std::filesystem::current_path[abi:cxx11]()'
/home/username/prog/bots/src/ui/dir_a/file_a.cpp:35: undefined reference to `std::filesystem::create_directories(std::filesystem::__cxx11::path const&)'
CMakeFiles/ProjectName.dir/src/ui/dir_a/file_a.cpp.o: In function `std::filesystem::__cxx11::path::operator+=(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
/usr/include/c++/8/bits/fs_path.h:817: undefined reference to `std::filesystem::__cxx11::path::_M_split_cmpts()'
CMakeFiles/ProjectName.dir/src/ui/dir_a/file_a.cpp.o: In function `std::filesystem::__cxx11::path::operator+=(char const*)':
/usr/include/c++/8/bits/fs_path.h:825: undefined reference to `std::filesystem::__cxx11::path::_M_split_cmpts()'
CMakeFiles/ProjectName.dir/src/ui/dir_a/file_a.cpp.o: In function `std::filesystem::exists(std::filesystem::__cxx11::path const&)':
/usr/include/c++/8/bits/fs_ops.h:121: undefined reference to `std::filesystem::status(std::filesystem::__cxx11::path const&)'
CMakeFiles/ProjectName.dir/src/ui/dir_b/file_b.cpp.o: In function `ProjectName::ClassName::update[abi:cxx11]()':
/home/username/prog/bots/src/ui/dir_b/file_b.cpp:30: undefined reference to `std::filesystem::current_path[abi:cxx11]()'
/home/username/prog/bots/src/ui/dir_b/file_b.cpp:34: undefined reference to `std::filesystem::create_directories(std::filesystem::__cxx11::path const&)'
/home/username/prog/bots/src/ui/dir_b/file_b.cpp:36: undefined reference to `std::filesystem::__cxx11::directory_iterator::operator*() const'
/home/username/prog/bots/src/ui/dir_b/file_b.cpp:40: undefined reference to `std::filesystem::__cxx11::path::replace_extension(std::filesystem::__cxx11::path const&)'
/home/username/prog/bots/src/ui/dir_b/file_b.cpp:36: undefined reference to `std::filesystem::__cxx11::directory_iterator::operator++()'
CMakeFiles/ProjectName.dir/src/ui/dir_b/file_b.cpp.o: In function `std::filesystem::__cxx11::path::path(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&&, std::filesystem::__cxx11::path::format)':
/usr/include/c++/8/bits/fs_path.h:177: undefined reference to `std::filesystem::__cxx11::path::_M_split_cmpts()'

它持续了大约一百行。

软件版本：

Ubuntu 18.04
g++-8 (installed with `apt`)
CMake 3.14.2

Answer 1

升级到g ++ 9可以解决此问题，但是如果有人知道如何解决该问题并仍然使用g ++ 8，我会接受该答案。

即使使用-lstdc ++ fs也无法链接std :: filesystem

1 个答案: