Index: tools/dsymutil/dsymutil.cpp
===================================================================
--- tools/dsymutil/dsymutil.cpp
+++ tools/dsymutil/dsymutil.cpp
@@ -181,43 +181,7 @@
   return true;
 }
 
-static std::error_code getUniqueFile(const llvm::Twine &Model, int &ResultFD,
-                                     llvm::SmallVectorImpl<char> &ResultPath) {
-  // If in NoOutput mode, use the createUniqueFile variant that
-  // doesn't open the file but still generates a somewhat unique
-  // name. In the real usage scenario, we'll want to ensure that the
-  // file is trully unique, and creating it is the only way to achieve
-  // that.
-  if (NoOutput)
-    return llvm::sys::fs::createUniqueFile(Model, ResultPath);
-  return llvm::sys::fs::createUniqueFile(Model, ResultFD, ResultPath);
-}
-
-static std::string getOutputFileName(llvm::StringRef InputFile,
-                                     bool TempFile = false) {
-  if (TempFile) {
-    llvm::SmallString<128> TmpFile;
-    llvm::sys::path::system_temp_directory(true, TmpFile);
-    llvm::StringRef Basename =
-        OutputFileOpt.empty() ? InputFile : llvm::StringRef(OutputFileOpt);
-    llvm::sys::path::append(TmpFile, llvm::sys::path::filename(Basename));
-
-    int FD;
-    llvm::SmallString<128> UniqueFile;
-    if (auto EC = getUniqueFile(TmpFile + ".tmp%%%%%.dwarf", FD, UniqueFile)) {
-      llvm::errs() << "error: failed to create temporary outfile '"
-                   << TmpFile << "': " << EC.message() << '\n';
-      return "";
-    }
-    llvm::sys::RemoveFileOnSignal(UniqueFile);
-    if (!NoOutput) {
-      // Close the file immediately. We know it is unique. It will be
-      // reopened and written to later.
-      llvm::raw_fd_ostream CloseImmediately(FD, true /* shouldClose */, true);
-    }
-    return UniqueFile.str();
-  }
-
+static std::string getOutputFileName(llvm::StringRef InputFile) {
   if (FlatOut) {
     // If a flat dSYM has been requested, things are pretty simple.
     if (OutputFileOpt.empty()) {
@@ -250,9 +214,16 @@
   return BundleDir.str();
 }
 
+static std::vector<sys::fs::TempFile> TempFileStore;
 void llvm::dsymutil::exitDsymutil(int ExitStatus) {
   // Cleanup temporary files.
-  llvm::sys::RunInterruptHandlers();
+  for (sys::fs::TempFile &Tmp : TempFileStore) {
+    if (Error E = Tmp.discard()) {
+      ExitStatus = 1;
+      consumeError(std::move(E));
+    }
+  }
+
   exit(ExitStatus);
 }
 
@@ -342,6 +313,10 @@
 
     // If there is more than one link to execute, we need to generate
     // temporary files.
+    llvm::SmallString<128> TmpModel;
+    llvm::sys::path::system_temp_directory(true, TmpModel);
+    llvm::sys::path::append(TmpModel, "dysym.tmp%%%%%.dwarf");
+
     bool NeedsTempFiles = !DumpDebugMap && (*DebugMapPtrsOrErr).size() != 1;
     llvm::SmallVector<MachOUtils::ArchAndFilename, 4> TempFiles;
     for (auto &Map : *DebugMapPtrsOrErr) {
@@ -356,18 +331,29 @@
                      << MachOUtils::getArchName(Map->getTriple().getArchName())
                      << ")\n";
 
-      std::string OutputFile = getOutputFileName(InputFile, NeedsTempFiles);
-
-      auto LinkLambda = [OutputFile, Options, &Map]() {
-        if (OutputFile.empty())
+      std::string OutputFile = getOutputFileName(InputFile);
+      std::unique_ptr<raw_fd_ostream> OS;
+      if (NeedsTempFiles) {
+        Expected<sys::fs::TempFile> T = sys::fs::TempFile::create(TmpModel);
+        if (!T) {
+          errs() << toString(T.takeError());
           exitDsymutil(1);
+        }
+        OS = make_unique<raw_fd_ostream>(T->FD, /*shouldClose*/ false);
+        OutputFile = T->TmpName;
+        TempFileStore.push_back(std::move(*T));
+      } else {
         std::error_code EC;
-        raw_fd_ostream OS(NoOutput ? "-" : OutputFile, EC, sys::fs::F_None);
+        OS = make_unique<raw_fd_ostream>(NoOutput ? "-" : OutputFile, EC,
+                                         sys::fs::F_None);
         if (EC) {
           errs() << OutputFile << ": " << EC.message();
           exitDsymutil(1);
         }
-        if (!linkDwarf(OS, *Map, Options))
+      }
+
+      auto LinkLambda = [&]() {
+        if (!linkDwarf(*OS, *Map, Options))
           exitDsymutil(1);
       };