我在 Xcode 中制作了一个使用 DropBox API 的 iPhone 应用程序。我遇到了 23 个错误，它们都被命名为 Apple Mach-O Linker Errors。我已将我的二进制文件与 dropbox 库以及:SystemConfiguration、QuartzCore、Security、CFNetwork、CoreGraphics、UIKit 和 Foundation 链接起来。我并没有使用所有这些框架，但 DropBox 告诉我必须导入其中的一些，而我正在使用其余的。
我该怎么办？
这是错误之一:
Ld /Users/Zach/Library/Developer/Xcode/DerivedData/SnapDrop-fwhwffwawcnkfwbxvokogcjaaahb/Build/Products/Debug-iphoneos/SnapDrop.app/SnapDrop normal armv7
cd /Users/Zach/Desktop/SnapDrop
setenv IPHONEOS_DEPLOYMENT_TARGET 7.0
setenv PATH "/Applications/Xcode5-DP3.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode5-DP3.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
/Applications/Xcode5-DP3.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch armv7 -isysroot /Applications/Xcode5-DP3.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk -L/Users/Zach/Library/Developer/Xcode/DerivedData/SnapDrop-fwhwffwawcnkfwbxvokogcjaaahb/Build/Products/Debug-iphoneos -F/Users/Zach/Library/Developer/Xcode/DerivedData/SnapDrop-fwhwffwawcnkfwbxvokogcjaaahb/Build/Products/Debug-iphoneos -F/Users/Zach/Desktop/SnapDrop -F/Users/Zach/Desktop/SnapDrop/../../Downloads/dropbox-ios-sync-sdk-1-1.1.0 -filelist /Users/Zach/Library/Developer/Xcode/DerivedData/SnapDrop-fwhwffwawcnkfwbxvokogcjaaahb/Build/Intermediates/SnapDrop.build/Debug-iphoneos/SnapDrop.build/Objects-normal/armv7/SnapDrop.LinkFileList -dead_strip -fobjc-arc -fobjc-link-runtime -miphoneos-version-min=7.0 -framework Dropbox -framework QuartzCore -framework SystemConfiguration -framework Security -framework CFNetwork -framework CoreGraphics -framework UIKit -framework Foundation -Xlinker -dependency_info -Xlinker /Users/Zach/Library/Developer/Xcode/DerivedData/SnapDrop-fwhwffwawcnkfwbxvokogcjaaahb/Build/Intermediates/SnapDrop.build/Debug-iphoneos/SnapDrop.build/Objects-normal/armv7/SnapDrop_dependency_info.dat -o /Users/Zach/Library/Developer/Xcode/DerivedData/SnapDrop-fwhwffwawcnkfwbxvokogcjaaahb/Build/Products/Debug-iphoneos/SnapDrop.app/SnapDrop
Undefined symbols for architecture armv7:
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::append(char const*)", referenced from:
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
dbx_url_encode(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in Dropbox(util.o)
dbx_build_url_with_params(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(util.o)
"operator new(unsigned long)", referenced from:
std::__1::__function::__func<HttpRequester::HttpRequester(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*), void*)::'lambda'(), std::__1::allocator<HttpRequester::HttpRequester(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*), void*)::'lambda'()>, void ()>::__clone() const in Dropbox(env.o)
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::reserve(unsigned long)", referenced from:
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
dbx_url_encode(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in Dropbox(util.o)
dbx_build_url_with_params(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(util.o)
"std::__1::chrono::system_clock::now()", referenced from:
std::__1::cv_status std::__1::condition_variable::wait_for<long long, std::__1::ratio<1ll, 1000ll> >(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::duration<long long, std::__1::ratio<1ll, 1000ll> > const&) in Dropbox(sync.o)
std::__1::cv_status std::__1::condition_variable::wait_for<long, std::__1::ratio<3600ll, 1ll> >(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::duration<long, std::__1::ratio<3600ll, 1ll> > const&) in Dropbox(api.o)
"std::__1::chrono::steady_clock::now()", referenced from:
std::__1::cv_status std::__1::condition_variable::wait_for<long long, std::__1::ratio<1ll, 1000ll> >(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::duration<long long, std::__1::ratio<1ll, 1000ll> > const&) in Dropbox(sync.o)
std::__1::cv_status std::__1::condition_variable::wait_for<long, std::__1::ratio<3600ll, 1ll> >(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::duration<long, std::__1::ratio<3600ll, 1ll> > const&) in Dropbox(api.o)
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::assign(char const*)", referenced from:
dbx_access_info::is_valid(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >&) const in Dropbox(sync.o)
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
dbx_build_url_with_params(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(util.o)
"std::__1::__throw_system_error(int, char const*)", referenced from:
std::__1::unique_lock<std::__1::mutex>::unlock() in Dropbox(transfer.o)
std::__1::unique_lock<std::__1::mutex>::lock() in Dropbox(transfer.o)
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::append(char const*, unsigned long)", referenced from:
dbx_build_url_with_params(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(util.o)
"std::__1::condition_variable::wait(std::__1::unique_lock<std::__1::mutex>&)", referenced from:
LifecycleManager::shutdown() in Dropbox(init.o)
dbx_env::log_upload_thread() in Dropbox(env.o)
"std::nothrow", referenced from:
_dropbox_env_init in Dropbox(init.o)
_dropbox_account_init in Dropbox(init.o)
HttpRequester::create(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*)) in Dropbox(env.o)
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
ThreadLocal<dbx_error_buf>::get() in Dropbox(util.o)
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::~basic_string()", referenced from:
dbx_env::~dbx_env() in Dropbox(init.o)
build_authed_url(dbx_account const*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(api.o)
dbx_request_json(dbx_account*, HttpRequester&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, char const*, int, std::initializer_list<int> const&, std::__1::unique_ptr<json_t, json_deleter>&) in Dropbox(api.o)
_dropbox_api_unlink in Dropbox(api.o)
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
dbx_upload_log_file(dbx_env const*, HttpRequester&, char const*, long long, long long, char const*, long long) in Dropbox(api.o)
dbx_build_url_with_params(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(util.o)
...
"std::__1::condition_variable::notify_all()", referenced from:
LifecycleManager::kick_cvars() in Dropbox(init.o)
LifecycleManager::ThreadRegistration::~ThreadRegistration() in Dropbox(transfer.o)
LifecycleManager::ThreadRegistration::ThreadRegistration(LifecycleManager&) in Dropbox(transfer.o)
dbx_env::dump_log_buffer() const in Dropbox(env.o)
dbx_env::log_upload_thread() in Dropbox(env.o)
"std::__1::condition_variable::~condition_variable()", referenced from:
_dropbox_account_init in Dropbox(init.o)
_dropbox_account_destroy in Dropbox(init.o)
dbx_env::~dbx_env() in Dropbox(init.o)
__GLOBAL__I_a in Dropbox(env.o)
"std::__1::mutex::unlock()", referenced from:
_dropbox_set_online in Dropbox(init.o)
_dropbox_lib_setup in Dropbox(init.o)
_dropbox_env_shutdown in Dropbox(init.o)
_dropbox_account_init in Dropbox(init.o)
_dropbox_account_shutdown in Dropbox(init.o)
void LifecycleManager::all_lock_helper<void, dropbox_set_online::$_0>(vq_node<std::__1::mutex&>*, dropbox_set_online::$_0) in Dropbox(init.o)
LifecycleManager::shutdown() in Dropbox(init.o)
...
"operator new(unsigned long, std::nothrow_t const&)", referenced from:
_dropbox_env_init in Dropbox(init.o)
_dropbox_account_init in Dropbox(init.o)
HttpRequester::create(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*)) in Dropbox(env.o)
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
ThreadLocal<dbx_error_buf>::get() in Dropbox(util.o)
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::push_back(char)", referenced from:
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
dbx_url_encode(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in Dropbox(util.o)
dbx_build_url_with_params(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(util.o)
"std::__1::condition_variable::__do_timed_wait(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::time_point<std::__1::chrono::system_clock, std::__1::chrono::duration<long long, std::__1::ratio<1ll, 1000000000ll> > >)", referenced from:
std::__1::cv_status std::__1::condition_variable::wait_for<long long, std::__1::ratio<1ll, 1000ll> >(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::duration<long long, std::__1::ratio<1ll, 1000ll> > const&) in Dropbox(sync.o)
std::__1::cv_status std::__1::condition_variable::wait_for<long, std::__1::ratio<3600ll, 1ll> >(std::__1::unique_lock<std::__1::mutex>&, std::__1::chrono::duration<long, std::__1::ratio<3600ll, 1ll> > const&) in Dropbox(api.o)
"std::__1::mutex::~mutex()", referenced from:
_dropbox_account_init in Dropbox(init.o)
_dropbox_account_destroy in Dropbox(init.o)
dbx_env::~dbx_env() in Dropbox(init.o)
__GLOBAL__I_a in Dropbox(init.o)
__GLOBAL__I_a in Dropbox(env.o)
"operator delete(void*)", referenced from:
_dropbox_env_destroy in Dropbox(init.o)
_dropbox_account_init in Dropbox(init.o)
_dropbox_account_destroy in Dropbox(init.o)
dbx_env::log_upload_thread() in Dropbox(env.o)
std::__1::__function::__func<HttpRequester::HttpRequester(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*), void*)::'lambda'(), std::__1::allocator<HttpRequester::HttpRequester(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*), void*)::'lambda'()>, void ()>::~__func() in Dropbox(env.o)
std::__1::__function::__func<HttpRequester::HttpRequester(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*), void*)::'lambda'(), std::__1::allocator<HttpRequester::HttpRequester(dbx_env*, LifecycleManager&, std::__1::mutex*, void*, void (*)(void*), void*)::'lambda'()>, void ()>::destroy_deallocate() in Dropbox(env.o)
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
...
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__init(char const*, unsigned long)", referenced from:
dbx_env::dbx_env(dbx_http const*, dbx_env_config const*) in Dropbox(init.o)
build_authed_url(dbx_account const*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(api.o)
_dropbox_api_unlink in Dropbox(api.o)
dbx_api_account_info(dbx_account*, std::__1::unique_ptr<dbx_account_info, dbx_account_info_deleter>*, std::__1::unique_ptr<dbx_access_info, std::__1::default_delete<dbx_access_info> >*, HttpRequester&, int) in Dropbox(api.o)
dbx_upload_log_file(dbx_env const*, HttpRequester&, char const*, long long, long long, char const*, long long) in Dropbox(api.o)
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::basic_string(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&)", referenced from:
build_authed_url(dbx_account const*, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::initializer_list<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&) in Dropbox(api.o)
dbx_upload_log_file(dbx_env const*, HttpRequester&, char const*, long long, long long, char const*, long long) in Dropbox(api.o)
"std::__1::mutex::lock()", referenced from:
_dropbox_set_online in Dropbox(init.o)
_dropbox_lib_setup in Dropbox(init.o)
_dropbox_env_shutdown in Dropbox(init.o)
_dropbox_account_init in Dropbox(init.o)
_dropbox_account_shutdown in Dropbox(init.o)
void LifecycleManager::all_lock_helper<void, dropbox_set_online::$_0>(vq_node<std::__1::mutex&>*, dropbox_set_online::$_0) in Dropbox(init.o)
LifecycleManager::shutdown() in Dropbox(init.o)
...
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)
最佳答案
您没有提到添加 libc++.dylib。每https://www.dropbox.com/developers/sync/sdks/ios :
Ensure that you have CFNetwork.framework, Security.framework, SystemConfiguration.framework, QuartzCore.framework, and libc++.dylib added to your project. To do this, select your project file in the file explorer, select your target, and select the Build Phases sub-tab. Under Link Binary with Libraries, press the + button, select CFNetwork.framework, and press Add. Repeat for Security.framework, SystemConfiguration.framework, QuartzCore.framework, and libc++.dylib.
如果设置说明中没有提到 libc++.dylib，请告诉我。
关于c++ - 许多 : 'Apple Mach-O Linker Errors' ，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17773180/
我正在尝试测试是否存在表单。我是Rails新手。我的new.html.erb_spec.rb文件的内容是:require'spec_helper'describe"messages/new.html.erb"doit"shouldrendertheform"dorender'/messages/new.html.erb'reponse.shouldhave_form_putting_to(@message)with_submit_buttonendendView本身，new.html.erb，有代码:当我运行rspec时，它失败了:1)messages/new.html.erbshou
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我花了三天的时间用头撞墙，试图弄清楚为什么简单的“rake”不能通过我的规范文件。如果您遇到这种情况:任何文件夹路径中都不要有空格!。严重地。事实上，从现在开始，您命名的任何内容都没有空格。这是我的控制台输出:(在/Users/*****/Desktop/LearningRuby/learn_ruby)$rake/Users/*******/Desktop/LearningRuby/learn_ruby/00_hello/hello_spec.rb:116:in`require':cannotloadsuchfile--hello(LoadError) 最佳
我已经像这样安装了一个新的Rails项目:$railsnewsite它执行并到达:bundleinstall但是当它似乎尝试安装依赖项时我得到了这个错误Gem::Ext::BuildError:ERROR:Failedtobuildgemnativeextension./System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/rubyextconf.rbcheckingforlibkern/OSAtomic.h...yescreatingMakefilemake"DESTDIR="cleanmake"DESTDIR="
关闭。这个问题需要detailsorclarity.它目前不接受答案。想改进这个问题吗？通过editingthispost添加细节并澄清问题.关闭8年前。Improvethisquestion在首页我有:汽车:VolvoSaabMercedesAudistatic_pages_spec.rb中的测试代码:it"shouldhavetherightselect"dovisithome_pathit{shouldhave_select('cars',:options=>['volvo','saab','mercedes','audi'])}end响应是rspec./spec/request
似乎无法为此找到有效的答案。我正在阅读Rails教程的第10章第10.1.2节，但似乎无法使邮件程序预览正常工作。我发现处理错误的所有答案都与教程的不同部分相关，我假设我犯的错误正盯着我的脸。我已经完成并将教程中的代码复制/粘贴到相关文件中，但到目前为止，我还看不出我输入的内容与教程中的内容有什么区别。到目前为止，建议是在函数定义中添加或删除参数user，但这并没有解决问题。触发错误的url是http://localhost:3000/rails/mailers/user_mailer/account_activation.http://localhost:3000/rails/mai