objective-c - 部署到 10.6 时出现 ARC 错误

Question

我的应用程序在 10.7 上运行和测试，但后来意识到我也需要它才能在早期版本上运行。不幸的是，我从一开始就使用 ARC 启动了这个项目。

现在我的build设置是调试基础 sdk:10.7，发布基础 sdk:10.6。当我尝试归档我的应用程序时，出现以下错误:

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)

这看起来像是 ARC 的问题，但我不知道从哪里开始解决这个问题。有什么建议么？谢谢。

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。尽管在这个问题中有详细说明，但有一些注意事项:How to deploy to Snow Leopard with ARC enabled