diff --git a/runtime/oat_file_assistant.cc b/runtime/oat_file_assistant.cc
index 8d5418d..99080f6 100644
--- a/runtime/oat_file_assistant.cc
+++ b/runtime/oat_file_assistant.cc
@@ -662,6 +662,13 @@
 bool OatFileAssistant::GenerateOatFile(std::string* error_msg) {
   CHECK(error_msg != nullptr);
 
+  Runtime* runtime = Runtime::Current();
+  if (!runtime->IsDex2OatEnabled()) {
+    *error_msg = "Generation of oat file for dex location " + dex_location_
+      + " not attempted because dex2oat is disabled.";
+    return false;
+  }
+
   if (OatFileName() == nullptr) {
     *error_msg = "Generation of oat file for dex location " + dex_location_
       + " not attempted because the oat file name could not be determined.";
@@ -669,17 +676,6 @@
   }
   const std::string& oat_file_name = *OatFileName();
 
-  Runtime* runtime = Runtime::Current();
-  if (!runtime->IsDex2OatEnabled()) {
-    *error_msg = "Generation of oat file " + oat_file_name
-      + " not attempted because dex2oat is disabled";
-    return false;
-  }
-
-  std::vector<std::string> args;
-  args.push_back("--dex-file=" + dex_location_);
-  args.push_back("--oat-file=" + oat_file_name);
-
   // dex2oat ignores missing dex files and doesn't report an error.
   // Check explicitly here so we can detect the error properly.
   // TODO: Why does dex2oat behave that way?
@@ -688,9 +684,36 @@
     return false;
   }
 
+  std::unique_ptr<File> oat_file;
+  oat_file.reset(OS::CreateEmptyFile(oat_file_name.c_str()));
+  if (oat_file.get() == nullptr) {
+    *error_msg = "Generation of oat file " + oat_file_name
+      + " not attempted because the oat file could not be created.";
+    return false;
+  }
+
+  if (fchmod(oat_file->Fd(), 0644) != 0) {
+    *error_msg = "Generation of oat file " + oat_file_name
+      + " not attempted because the oat file could not be made world readable.";
+    oat_file->Erase();
+    return false;
+  }
+
+  std::vector<std::string> args;
+  args.push_back("--dex-file=" + dex_location_);
+  args.push_back("--oat-fd=" + std::to_string(oat_file->Fd()));
+  args.push_back("--oat-location=" + oat_file_name);
+
   if (!Dex2Oat(args, error_msg)) {
     // Manually delete the file. This ensures there is no garbage left over if
     // the process unexpectedly died.
+    oat_file->Erase();
+    TEMP_FAILURE_RETRY(unlink(oat_file_name.c_str()));
+    return false;
+  }
+
+  if (oat_file->FlushCloseOrErase() != 0) {
+    *error_msg = "Unable to close oat file " + oat_file_name;
     TEMP_FAILURE_RETRY(unlink(oat_file_name.c_str()));
     return false;
   }
diff --git a/runtime/oat_file_assistant_test.cc b/runtime/oat_file_assistant_test.cc
index 2c81edd..c54d7f8 100644
--- a/runtime/oat_file_assistant_test.cc
+++ b/runtime/oat_file_assistant_test.cc
@@ -849,6 +849,38 @@
   EXPECT_FALSE(ofm.OatFileExists());
 }
 
+// Case: We have a DEX file but can't write the oat file.
+// Expect: We should fail to make the oat file up to date.
+TEST_F(OatFileAssistantTest, LoadDexUnwriteableAlternateOat) {
+  std::string dex_location = GetScratchDir() + "/LoadDexUnwriteableAlternateOat.jar";
+
+  // Make the oat location unwritable by inserting some non-existent
+  // intermediate directories.
+  std::string oat_location = GetScratchDir() + "/foo/bar/LoadDexUnwriteableAlternateOat.oat";
+
+  Copy(GetDexSrc1(), dex_location);
+
+  OatFileAssistant oat_file_assistant(
+      dex_location.c_str(), oat_location.c_str(), kRuntimeISA, true);
+  std::string error_msg;
+  ASSERT_FALSE(oat_file_assistant.MakeUpToDate(&error_msg));
+
+  std::unique_ptr<OatFile> oat_file = oat_file_assistant.GetBestOatFile();
+  ASSERT_TRUE(oat_file.get() == nullptr);
+}
+
+// Case: We don't have a DEX file and can't write the oat file.
+// Expect: We should fail to generate the oat file without crashing.
+TEST_F(OatFileAssistantTest, GenNoDex) {
+  std::string dex_location = GetScratchDir() + "/GenNoDex.jar";
+  std::string oat_location = GetScratchDir() + "/GenNoDex.oat";
+
+  OatFileAssistant oat_file_assistant(
+      dex_location.c_str(), oat_location.c_str(), kRuntimeISA, true);
+  std::string error_msg;
+  ASSERT_FALSE(oat_file_assistant.GenerateOatFile(&error_msg));
+}
+
 // Turn an absolute path into a path relative to the current working
 // directory.
 static std::string MakePathRelative(std::string target) {