ios - 段错误 11，Xcode 8.2.1，Swift 3

Question

我正在尝试创建我的应用程序的存档，但在为 iOS 设备构建时遇到段错误。我在为模拟器构建时没有遇到这个问题。到目前为止，我有:

• 清理了我的项目
• 清理了我的构建文件夹
• 删除了我的派生数据文件夹
• 已安装 Mac OS Sierra
• 更新到 Sierra 后安装了额外的 Xcode 工具
• 多次重启 Xcode/计算机

错误通常如下所示:

Call parameter type does not match function signature!
0  swift                    0x000000010f4ab3ad PrintStackTraceSignalHandler(void*) + 45
1  swift                    0x000000010f4aab56 SignalHandler(int) + 790
2  libsystem_platform.dylib 0x00007fffb1b28bba _sigtramp + 26
3  libsystem_platform.dylib 0x000000011033a000 _sigtramp + 1585517664
4  swift                    0x000000010f3038e8 llvm::TypeFinder::incorporateValue(llvm::Value const*) + 296
5  swift                    0x000000010f3032fa llvm::TypeFinder::run(llvm::Module const&, bool) + 682
6  swift                    0x000000010f1c827e (anonymous namespace)::TypePrinting::incorporateTypes(llvm::Module const&) + 30
7  swift                    0x000000010f1c9bdb printAsOperandImpl(llvm::Value const&, llvm::raw_ostream&, bool, llvm::ModuleSlotTracker&) + 171
8  swift                    0x000000010f30c633 (anonymous namespace)::VerifierSupport::Write(llvm::Value const*) + 67
9  swift                    0x000000010f31616e (anonymous namespace)::Verifier::VerifyCallSite(llvm::CallSite) + 590
10 swift                    0x000000010f318ef3 (anonymous namespace)::Verifier::visitCallInst(llvm::CallInst&) + 35
11 swift                    0x000000010f329ac1 (anonymous namespace)::VerifierLegacyPass::runOnFunction(llvm::Function&) + 1649
12 swift                    0x000000010f2e089d llvm::FPPassManager::runOnFunction(llvm::Function&) + 973
13 swift                    0x000000010f2e02ab llvm::FPPassManager::runOnModule(llvm::Module&) + 43
14 swift                    0x000000010f2e977a llvm::legacy::PassManager::run(llvm::Module&) + 1514
15 swift                    0x000000010c605901 performLLVM(swift::IRGenOptions&, swift::DiagnosticEngine&, llvm::sys::SmartMutex<false>*, llvm::GlobalVariable*, llvm::Module*, llvm::TargetMachine*, llvm::StringRef) + 5921
16 swift                    0x000000010c6038c1 performIRGeneration(swift::IRGenOptions&, swift::ModuleDecl*, swift::SILModule*, llvm::StringRef, llvm::LLVMContext&, swift::SourceFile*, unsigned int) + 2625
17 swift                    0x000000010c4b8f31 performCompile(swift::CompilerInstance&, swift::CompilerInvocation&, llvm::ArrayRef<char const*>, int&, swift::FrontendObserver*) + 23777
18 swift                    0x000000010c4b12b3 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 17859
19 swift                    0x000000010c46d5cf main + 8239
20 libdyld.dylib            0x00007fffb191b255 start + 1

在堆栈转储中，有这一行:

2.  Running pass 'Module Verifier' on function '@_TZFC12MyAppName23MyClassNameg13nextImagePathV10Foundation3URL'

我认为这表明在编译静态计算变量 nextImagePath 时抛出了错误，它返回一个 URL 到文件路径。在内部，这依赖于一些其他计算变量和方法 nextFilePathForDirectoryAtURL。总而言之，代码如下所示:

/* 
 * This is the offending computed variable.
 */

static var nextImagePath: URL {
  return nextFilePathForDirectoryAtURL(imageDirectory, withExtension: "jpg");
}

/*
 * The method called by above variable. It looks through all the
 * files in a directory, finds the one with the highest index,
 * and returns a new path by incrementing the highest index by 1.
 */

fileprivate static func nextFilePathForDirectoryAtURL(_ url: URL, withExtension ext: String) -> URL {
  guard let files = try? FileManager.default.contentsOfDirectory(
    at: url,
    includingPropertiesForKeys: nil,
    options: .skipsHiddenFiles) else {
      fatalError("Could not create next file path for directory at url: \(url)");
  }

  var maxFileNumber = 0;
  for file in files {
    let fileName = file.deletingPathExtension().lastPathComponent;

    guard
      let fileNumber = Int(fileName),
      file.pathExtension.lowercased() == ext.lowercased()
      else { continue }

    maxFileNumber = max(maxFileNumber, fileNumber);
  }

  return url.appendingPathComponent("\(maxFileNumber + 1).\(ext)");
}

/*
 * Some supporting computed variables for constructing directories.
 */

fileprivate static var libraryDirectory: URL {
  guard let url = try? FileManager.default.url(
    for: .libraryDirectory,
    in: .userDomainMask,
    appropriateFor: nil,
    create: true) else {
      fatalError("Could not create library directory url.");
  }

  return url;
}

fileprivate static var documentSetDirectory: URL {
  let directory = libraryDirectory.appendingPathComponent("MemberDocumentSets");

  try? FileManager.default.createDirectory(
    at: directory,
    withIntermediateDirectories: true,
    attributes: nil);

  return directory;
}

fileprivate static var imageDirectory: URL {
  let directory = documentSetDirectory.appendingPathComponent("Images");

  try? FileManager.default.createDirectory(
    at: directory,
    withIntermediateDirectories: true,
    attributes: nil);

  return directory;
}

我不太确定为什么会发生此错误，或者为什么在为模拟器构建时不会发生此错误。我一直在尝试找到大约 5 个小时的答案，但没有运气，所以我想发帖。任何帮助是极大的赞赏。谢谢!

Answer 1

好吧，几个小时后，我能够推断出错误是由 documentSetDirectory 计算变量引起的。显然，编译器不喜欢将 try 语句的结果转换为可选语句。相反，我必须将语句包装在 do catch block 中。以下代码解决了我的问题:

fileprivate static var documentSetDirectory: URL {
  let directory = libraryDirectory.appendingPathComponent("MemberDocumentSets");

  do {
    try FileManager.default.createDirectory(
      at: directory,
      withIntermediateDirectories: true,
      attributes: nil);
  } catch {

    /* 
     * Do nothing. So why have a catch block at all? Because: for some reason
     * this prevents the compiler from spitting up. Apparently it didn't like
     * converting the `try` to an optional here. Weirdly, I'm still doing the
     * optional conversion elsewhere in this same class without issue (see
     * computed variables below).
     *
     * ¯\_(ツ)_/¯
     */
  }

  return directory;
}

fileprivate static var imageDirectory: URL {
  let directory = documentSetDirectory.appendingPathComponent("Images");

  try? FileManager.default.createDirectory(
    at: directory,
    withIntermediateDirectories: true,
    attributes: nil);

  return directory;
}

显然，这一定是编译器的错误。我创建了一个空项目并复制了原始代码，但编译没有问题，我找不到导致相同错误的任何项目设置差异。无论如何，我很高兴找到了解决方案，希望它能在未来为一些可怜的人节省一些时间。