Allocate global objects so that their destructors don't run. (#6849)

Fixes #6844.

Author: wilhuff

Firestore/core/src/auth/user.cc

@@ -32,8 +32,8 @@ User::User(std::string uid) : uid_{std::move(uid)}, is_authenticated_{true} {
 }
 
 const User& User::Unauthenticated() {
-  static const User kUnauthenticated;
-  return kUnauthenticated;
+  static const User* kUnauthenticated = new User();
+  return *kUnauthenticated;
 }
 
 }  // namespace auth

Firestore/core/src/immutable/array_sorted_map.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 Google
+ * Copyright 2018 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -326,9 +326,11 @@ class ArraySortedMap : public SortedMapBase {
 
  private:
   static array_pointer EmptyArray() {
-    static const array_pointer kEmptyArray =
-        std::make_shared<const array_type>();
-    return kEmptyArray;
+    static const array_pointer* kEmptyArray = [] {
+      auto array = new array_type();
+      return new std::shared_ptr<const array_type>(array);
+    }();
+    return *kEmptyArray;
   }
 
   static array_pointer SortedArray(std::initializer_list<value_type> entries,

Firestore/core/src/immutable/llrb_node.h

@@ -162,18 +162,18 @@ class LlrbNode : public SortedMapBase {
    * Returns a shared Empty node, to cut down on allocations in the base case.
    */
   static const std::shared_ptr<Rep>& EmptyRep() {
-    static const std::shared_ptr<Rep> empty_rep = [] {
-      auto empty = std::make_shared<Rep>(Rep{std::pair<K, V>{}, Color::Black,
-                                             /* size= */ 0u, LlrbNode{nullptr},
-                                             LlrbNode{nullptr}});
+    static const std::shared_ptr<Rep>* empty_rep = [] {
+      auto rep = new Rep{std::pair<K, V>{}, Color::Black,
+                         /* size= */ 0u, LlrbNode{nullptr}, LlrbNode{nullptr}};
+      auto empty = new std::shared_ptr<Rep>{rep};
 
       // Set up the empty Rep such that you can traverse infinitely down left
       // and right links.
-      empty->left_.rep_ = empty;
-      empty->right_.rep_ = empty;
+      (*empty)->left_.rep_ = *empty;
+      (*empty)->right_.rep_ = *empty;
       return empty;
     }();
-    return empty_rep;
+    return *empty_rep;
   }
 
   /**

Firestore/core/src/local/leveldb_transaction.cc

@@ -146,6 +146,7 @@ LevelDbTransaction::LevelDbTransaction(DB* db,
 }
 
 const ReadOptions& LevelDbTransaction::DefaultReadOptions() {
+  // ReadOptions is trivial so it does not need to be heap-allocated.
   static ReadOptions options = [] {
     ReadOptions read_options;
     read_options.verify_checksums = true;
@@ -155,6 +156,7 @@ const ReadOptions& LevelDbTransaction::DefaultReadOptions() {
 }
 
 const WriteOptions& LevelDbTransaction::DefaultWriteOptions() {
+  // WriteOptions is trivial so it does not need to be heap-allocated.
   static WriteOptions options;
   return options;
 }

Firestore/core/src/model/document_key.cc

@@ -59,8 +59,8 @@ DocumentKey DocumentKey::FromSegments(std::initializer_list<std::string> list) {
 }
 
 const DocumentKey& DocumentKey::Empty() {
-  static const DocumentKey empty;
-  return empty;
+  static const DocumentKey* empty = new DocumentKey();
+  return *empty;
 }
 
 bool DocumentKey::IsDocumentKey(const ResourcePath& path) {

Firestore/core/src/remote/datastore.cc

@@ -334,13 +334,14 @@ bool Datastore::IsPermanentWriteError(const Status& error) {
 
 std::string Datastore::GetAllowlistedHeadersAsString(
     const GrpcCall::Metadata& headers) {
-  static std::unordered_set<std::string> allowlist = {
+  static auto* allowlist = new std::unordered_set<std::string>{
       "date", "x-google-backends", "x-google-netmon-label", "x-google-service",
       "x-google-gfe-request-trace"};
 
   std::string result;
+  auto end = allowlist->end();
   for (const auto& kv : headers) {
-    if (allowlist.find(MakeString(kv.first)) != allowlist.end()) {
+    if (allowlist->find(MakeString(kv.first)) != end) {
       absl::StrAppend(&result, MakeStringView(kv.first), ": ",
                       MakeStringView(kv.second), "\n");
     }

Firestore/core/src/remote/grpc_connection.cc

@@ -125,8 +125,8 @@ class HostConfigMap {
 };
 
 HostConfigMap& Config() {
-  static HostConfigMap config_by_host;
-  return config_by_host;
+  static auto* config_by_host = new HostConfigMap();
+  return *config_by_host;
 }
 
 std::string GetCppLanguageToken() {
@@ -170,8 +170,8 @@ class ClientLanguageToken {
 };
 
 ClientLanguageToken& LanguageToken() {
-  static ClientLanguageToken token;
-  return token;
+  static auto* token = new ClientLanguageToken();
+  return *token;
 }
 
 void AddCloudApiHeader(grpc::ClientContext& context) {

Firestore/core/src/util/autoid.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Google
+ * Copyright 2017 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,14 +24,16 @@
 namespace firebase {
 namespace firestore {
 namespace util {
-
 namespace {
 
 const int kAutoIdLength = 20;
 const char kAutoIdAlphabet[] =
     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
 
-SecureRandom shared_random;
+SecureRandom& GetSharedRandom() {
+  static auto* shared_random = new SecureRandom();
+  return *shared_random;
+}
 
 }  // namespace
 
@@ -44,6 +46,7 @@ std::string CreateAutoId() {
   //   * uniform_int_distribution is inclusive on both sizes
   std::uniform_int_distribution<int> letters(0, sizeof(kAutoIdAlphabet) - 2);
 
+  SecureRandom& shared_random = GetSharedRandom();
   for (int i = 0; i < kAutoIdLength; i++) {
     int rand_index = letters(shared_random);
     auto_id.append(1, kAutoIdAlphabet[rand_index]);

Firestore/core/src/util/filesystem_common.cc

@@ -27,8 +27,8 @@ namespace firestore {
 namespace util {
 
 Filesystem* Filesystem::Default() {
-  static Filesystem filesystem;
-  return &filesystem;
+  static auto* filesystem = new Filesystem();
+  return filesystem;
 }
 
 Status Filesystem::RecursivelyCreateDir(const Path& path) {