Question

我的应用程序在10.7上运行并经过测试，但后来意识到我需要它才能在早期版本上运行。不幸的是，我从一开始就用ARC开始了这个项目。

现在我的构建设置是debug base sdk：10.7，并且release base sdk：10.6。当我尝试存档我的应用时，我收到以下错误：

Undefined symbols for architecture x86_64:
"_objc_retain", referenced from:
  +[__ARCLite__ load] in libarclite_macosx.a(arclite.o)
  -[AppDelegate applicationDidFinishLaunching:] in AppDelegate.o
  -[AppDelegate managedObjectModel] in AppDelegate.o
  -[AppDelegate persistentStoreCoordinator] in AppDelegate.o
  -[AppDelegate managedObjectContext] in AppDelegate.o
  -[AppDelegate windowWillReturnUndoManager:] in AppDelegate.o
  -[AppDelegate saveAction:] in AppDelegate.o
  ...
 (maybe you meant: _objc_retainedObject)
"_objc_release", referenced from:
  -[AppDelegate applicationDidFinishLaunching:] in AppDelegate.o
  -[AppDelegate applicationFilesDirectory] in AppDelegate.o
  -[AppDelegate managedObjectModel] in AppDelegate.o
  -[AppDelegate persistentStoreCoordinator] in AppDelegate.o
  -[AppDelegate managedObjectContext] in AppDelegate.o
  -[AppDelegate windowWillReturnUndoManager:] in AppDelegate.o
  -[AppDelegate saveAction:] in AppDelegate.o
  ...
"_objc_retainAutoreleasedReturnValue", referenced from:
  -[AppDelegate applicationFilesDirectory] in AppDelegate.o
  -[AppDelegate managedObjectModel] in AppDelegate.o
  -[AppDelegate persistentStoreCoordinator] in AppDelegate.o
  -[AppDelegate managedObjectContext] in AppDelegate.o
  -[AppDelegate windowWillReturnUndoManager:] in AppDelegate.o
  -[AppDelegate saveAction:] in AppDelegate.o
  -[AppDelegate applicationShouldTerminate:] in AppDelegate.o
  ...
"_objc_autoreleaseReturnValue", referenced from:
  -[AppDelegate applicationFilesDirectory] in AppDelegate.o
  -[AppDelegate managedObjectModel] in AppDelegate.o
  -[AppDelegate persistentStoreCoordinator] in AppDelegate.o
  -[AppDelegate managedObjectContext] in AppDelegate.o
  -[AppDelegate windowWillReturnUndoManager:] in AppDelegate.o
  -[MainWindowController viewForTag:] in MainWindowController.o
  -[MainWindowController tableView:objectValueForTableColumn:row:] in MainWindowController.o
  ...
"_objc_storeStrong", referenced from:
  -[AppDelegate persistentStoreCoordinator] in AppDelegate.o
  -[AppDelegate saveAction:] in AppDelegate.o
  -[AppDelegate applicationShouldTerminate:] in AppDelegate.o
  -[AppDelegate .cxx_destruct] in AppDelegate.o
  -[MainWindowController init] in MainWindowController.o
  -[MainWindowController viewForTag:] in MainWindowController.o
  -[MainWindowController showUserFinderView:] in MainWindowController.o
  ...
"_objc_retainAutoreleaseReturnValue", referenced from:
  +[MainWindowController sharedInstance] in MainWindowController.o
  -[FileMetaData getFileName] in FileMetaData.o
  -[FileMetaData getLastHash] in FileMetaData.o
  -[FileMetaData getCreationDate] in FileMetaData.o
  -[FileMetaData getLastModified] in FileMetaData.oe
  -[FileMetaData getLocalPath] in FileMetaData.o
  ...
"_objc_autorelease", referenced from:
  -[SBJsonParser objectWithString:error:] in SBJsonParser.o
  -[SBJsonTokeniser getStringToken:] in SBJsonTokeniser.o
  -[SBJsonTokeniser getNumberToken:] in SBJsonTokeniser.o
  -[SBJsonUTF8Stream getRetainedStringFragment:] in SBJsonUTF8Stream.o
  -[SBJsonWriter stringWithObject:error:] in SBJsonWriter.o
"_objc_retainAutorelease", referenced from:
  -[SBJsonTokeniser getStringToken:] in SBJsonTokeniser.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

这看起来像ARC的一个问题，但我不知道从哪里开始修复它。有什么建议？感谢。

Answer 1

您需要将SDK设置为10.7 - 但您可以将部署目标设置为10.6。虽然在这个问题中详细说明了一些注意事项：How to deploy to Snow Leopard with ARC enabled

Answer 2

我今天遇到同样的信息时遇到了这个问题。我将SDK设置为10.7，部署目标设置为10.6，但仍然看到此消息。

我的项目主要是使用现有的手动保留释放代码，只有几个使用ARC的新文件。因此，我在主目标设置中禁用了ARC ，并通过将-fobjc-arc添加到每个文件的构建设置（在构建阶段下），为这两个文件选择性地启用了它。

在预感中，我在目标中启用了ARC，然后在每个文件设置中失败（删除了两个文件的标志，并将-fno-objc-arc添加到所有其他文件中）并且不再获得动态链接错误10.6。

部署到10.6时出现ARC错误

2 个答案: