Export of internal Abseil changes

--
7d0468a6610ed85586d5c87fd65de8dac5118923 by Derek Mauro <dmauro@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 313226473

--
1131ef6d116f5ce7d46537a82f300ea06dcaaa53 by Gennadiy Rozental <rogeeff@google.com>:

Migrate internal interface to use mutable references.

PiperOrigin-RevId: 312931131

--
96225212a9f5fbd0b38c71fe65539164992c7c3b by Laramie Leavitt <lar@google.com>:

Remove random/internal/distributions.h

This file was something of an historical artifact. All of the related
code has either been removed or migraged, and so the only remaining type
belongs with uniform_helper.h, as it is used to infer the return type
of the absl::Uniform method in a few cases.

PiperOrigin-RevId: 312878173

--
6dcbd5be58ad425e08740ff64088373ee7fe4a72 by Mark Barolak <mbar@google.com>:

Release the StrFormat test case for Cords to open source.

PiperOrigin-RevId: 312707974

--
34484d18dfb63a0a7ad6e2aaeb570e33592968be by Abseil Team <absl-team@google.com>:

Let Cord::Cord(string&&), Cord::operator=(string&&),
Cord::Append(string&&), and Cord::Prepend(string&&) steal string data
and embed it into the Cord as a single external chunk, instead of
copying it into flat chunks (at most 4083-byte each).

Stealing string data is faster, but it creates a long chunk, which leads
to a higher more memory usage if its subcords are created and outlive
the whole Cord.

These functions revert to copying the data if any of the following
conditions holds:
- string size is at most kMaxBytesToCopy (511), to avoid the overhead
  of an external chunk for short strings;
- less than half of string capacity is used, to avoid pinning to much
  unused memory.

PiperOrigin-RevId: 312683785
GitOrigin-RevId: 7d0468a6610ed85586d5c87fd65de8dac5118923
Change-Id: If79b5a1dfe6d53a8ddddbc7da84338f11fc4cfa3

16 files changed, 192 insertions, 195 deletions

diff --git a/absl/flags/commandlineflag.cc b/absl/flags/commandlineflag.cc
index 83d14c1b..cea57234 100644
--- a/absl/flags/commandlineflag.cc
+++ b/absl/flags/commandlineflag.cc
@@ -21,7 +21,7 @@ ABSL_NAMESPACE_BEGIN
 bool CommandLineFlag::IsRetired() const { return false; }
 bool CommandLineFlag::ParseFrom(absl::string_view value, std::string* error) {
   return ParseFrom(value, flags_internal::SET_FLAGS_VALUE,
-                   flags_internal::kProgrammaticChange, error);
+                   flags_internal::kProgrammaticChange, *error);
 }
 
 namespace flags_internal {
diff --git a/absl/flags/commandlineflag.h b/absl/flags/commandlineflag.h
index f09f1f70..43055d04 100644
--- a/absl/flags/commandlineflag.h
+++ b/absl/flags/commandlineflag.h
@@ -159,7 +159,7 @@ class CommandLineFlag {
   virtual bool ParseFrom(absl::string_view value,
                          flags_internal::FlagSettingMode set_mode,
                          flags_internal::ValueSource source,
-                         std::string* error) = 0;
+                         std::string& error) = 0;
 
   // Returns id of the flag's value type.
   virtual flags_internal::FlagFastTypeId TypeId() const = 0;
diff --git a/absl/flags/commandlineflag_test.cc b/absl/flags/commandlineflag_test.cc
index 352edccf..4b9718e9 100644
--- a/absl/flags/commandlineflag_test.cc
+++ b/absl/flags/commandlineflag_test.cc
@@ -129,57 +129,57 @@ TEST_F(CommandLineFlagTest, TestParseFromCurrentValue) {
       flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "11", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, &err));
+      *flag_01, "11", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 11);
   EXPECT_FALSE(
       flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "-123", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "-123", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), -123);
   EXPECT_FALSE(
       flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(!flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "xyz", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "xyz", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), -123);
   EXPECT_EQ(err, "Illegal value 'xyz' specified for flag 'int_flag'");
   EXPECT_FALSE(
       flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(!flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "A1", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, &err));
+      *flag_01, "A1", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), -123);
   EXPECT_EQ(err, "Illegal value 'A1' specified for flag 'int_flag'");
   EXPECT_FALSE(
       flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "0x10", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "0x10", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 16);
   EXPECT_FALSE(
       flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "011", flags::SET_FLAGS_VALUE, flags::kCommandLine, &err));
+      *flag_01, "011", flags::SET_FLAGS_VALUE, flags::kCommandLine, err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 11);
   EXPECT_TRUE(flags::PrivateHandleAccessor::IsSpecifiedOnCommandLine(*flag_01));
 
   EXPECT_TRUE(!flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, &err));
+      *flag_01, "", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, err));
   EXPECT_EQ(err, "Illegal value '' specified for flag 'int_flag'");
 
   auto* flag_02 = flags::FindCommandLineFlag("string_flag");
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_02, "xyz", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
-      &err));
+      *flag_02, "xyz", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(absl::GetFlag(FLAGS_string_flag), "xyz");
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_02, "", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, &err));
+      *flag_02, "", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange, err));
   EXPECT_EQ(absl::GetFlag(FLAGS_string_flag), "");
 }
 
@@ -191,15 +191,15 @@ TEST_F(CommandLineFlagTest, TestParseFromDefaultValue) {
   auto* flag_01 = flags::FindCommandLineFlag("int_flag");
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "111", flags::SET_FLAGS_DEFAULT, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "111", flags::SET_FLAGS_DEFAULT, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(flag_01->DefaultValue(), "111");
 
   auto* flag_02 = flags::FindCommandLineFlag("string_flag");
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_02, "abc", flags::SET_FLAGS_DEFAULT, flags::kProgrammaticChange,
-      &err));
+      *flag_02, "abc", flags::SET_FLAGS_DEFAULT, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(flag_02->DefaultValue(), "abc");
 }
 
@@ -211,25 +211,25 @@ TEST_F(CommandLineFlagTest, TestParseFromIfDefault) {
   auto* flag_01 = flags::FindCommandLineFlag("int_flag");
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "22", flags::SET_FLAG_IF_DEFAULT, flags::kProgrammaticChange,
-      &err))
+      *flag_01, "22", flags::SET_FLAG_IF_DEFAULT, flags::kProgrammaticChange,
+      err))
       << err;
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 22);
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "33", flags::SET_FLAG_IF_DEFAULT, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "33", flags::SET_FLAG_IF_DEFAULT, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 22);
   // EXPECT_EQ(err, "ERROR: int_flag is already set to 22");
 
   // Reset back to default value
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "201", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "201", flags::SET_FLAGS_VALUE, flags::kProgrammaticChange,
+      err));
 
   EXPECT_TRUE(flags::PrivateHandleAccessor::ParseFrom(
-      flag_01, "33", flags::SET_FLAG_IF_DEFAULT, flags::kProgrammaticChange,
-      &err));
+      *flag_01, "33", flags::SET_FLAG_IF_DEFAULT, flags::kProgrammaticChange,
+      err));
   EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 201);
   // EXPECT_EQ(err, "ERROR: int_flag is already set to 201");
 }
diff --git a/absl/flags/flag.h b/absl/flags/flag.h
index f84853ea..dd36e6c7 100644
--- a/absl/flags/flag.h
+++ b/absl/flags/flag.h
@@ -110,12 +110,12 @@ class Flag {
         impl_(nullptr) {}
 #endif
 
-  flags_internal::Flag<T>* GetImpl() const {
+  flags_internal::Flag<T>& GetImpl() const {
     if (!inited_.load(std::memory_order_acquire)) {
       absl::MutexLock l(flags_internal::GetGlobalConstructionGuard());
 
       if (inited_.load(std::memory_order_acquire)) {
-        return impl_;
+        return *impl_;
       }
 
       impl_ = new flags_internal::Flag<T>(
@@ -127,28 +127,28 @@ class Flag {
       inited_.store(true, std::memory_order_release);
     }
 
-    return impl_;
+    return *impl_;
   }
 
   // Public methods of `absl::Flag<T>` are NOT part of the Abseil Flags API.
   // See https://abseil.io/docs/cpp/guides/flags
-  bool IsRetired() const { return GetImpl()->IsRetired(); }
-  absl::string_view Name() const { return GetImpl()->Name(); }
-  std::string Help() const { return GetImpl()->Help(); }
-  bool IsModified() const { return GetImpl()->IsModified(); }
+  bool IsRetired() const { return GetImpl().IsRetired(); }
+  absl::string_view Name() const { return GetImpl().Name(); }
+  std::string Help() const { return GetImpl().Help(); }
+  bool IsModified() const { return GetImpl().IsModified(); }
   bool IsSpecifiedOnCommandLine() const {
-    return GetImpl()->IsSpecifiedOnCommandLine();
+    return GetImpl().IsSpecifiedOnCommandLine();
   }
-  std::string Filename() const { return GetImpl()->Filename(); }
-  std::string DefaultValue() const { return GetImpl()->DefaultValue(); }
-  std::string CurrentValue() const { return GetImpl()->CurrentValue(); }
+  std::string Filename() const { return GetImpl().Filename(); }
+  std::string DefaultValue() const { return GetImpl().DefaultValue(); }
+  std::string CurrentValue() const { return GetImpl().CurrentValue(); }
   template <typename U>
   inline bool IsOfType() const {
-    return GetImpl()->template IsOfType<U>();
+    return GetImpl().template IsOfType<U>();
   }
-  T Get() const { return GetImpl()->Get(); }
-  void Set(const T& v) { GetImpl()->Set(v); }
-  void InvokeCallback() { GetImpl()->InvokeCallback(); }
+  T Get() const { return GetImpl().Get(); }
+  void Set(const T& v) { GetImpl().Set(v); }
+  void InvokeCallback() { GetImpl().InvokeCallback(); }
 
   // The data members are logically private, but they need to be public for
   // this to be an aggregate type.
@@ -265,7 +265,7 @@ ABSL_NAMESPACE_END
 
 // ABSL_FLAG_IMPL macro definition conditional on ABSL_FLAGS_STRIP_NAMES
 #if !defined(_MSC_VER) || defined(__clang__)
-#define ABSL_FLAG_IMPL_FLAG_PTR(flag) &flag
+#define ABSL_FLAG_IMPL_FLAG_PTR(flag) flag
 #define ABSL_FLAG_IMPL_HELP_ARG(name)                      \
   absl::flags_internal::HelpArg<AbslFlagHelpGenFor##name>( \
       FLAGS_help_storage_##name)
diff --git a/absl/flags/flag_test.cc b/absl/flags/flag_test.cc
index 8d53ecd6..58a07999 100644
--- a/absl/flags/flag_test.cc
+++ b/absl/flags/flag_test.cc
@@ -150,21 +150,21 @@ DEFINE_CONSTRUCTED_FLAG(String, &TestMakeDflt<String>, kGenFunc);
 DEFINE_CONSTRUCTED_FLAG(UDT, &TestMakeDflt<UDT>, kGenFunc);
 
 template <typename T>
-bool TestConstructionFor(const flags::Flag<T>& f1, flags::Flag<T>* f2) {
+bool TestConstructionFor(const flags::Flag<T>& f1, flags::Flag<T>& f2) {
   EXPECT_EQ(f1.Name(), "f1");
   EXPECT_EQ(f1.Help(), "literal help");
   EXPECT_EQ(f1.Filename(), "file");
 
   flags::FlagRegistrar<T, false>(f2).OnUpdate(TestCallback);
 
-  EXPECT_EQ(f2->Name(), "f2");
-  EXPECT_EQ(f2->Help(), "dynamic help");
-  EXPECT_EQ(f2->Filename(), "file");
+  EXPECT_EQ(f2.Name(), "f2");
+  EXPECT_EQ(f2.Help(), "dynamic help");
+  EXPECT_EQ(f2.Filename(), "file");
 
   return true;
 }
 
-#define TEST_CONSTRUCTED_FLAG(T) TestConstructionFor(f1##T, &f2##T);
+#define TEST_CONSTRUCTED_FLAG(T) TestConstructionFor(f1##T, f2##T);
 
 TEST_F(FlagTest, TestConstruction) {
   TEST_CONSTRUCTED_FLAG(bool);
diff --git a/absl/flags/internal/flag.cc b/absl/flags/internal/flag.cc
index 35ae55fb..ee974244 100644
--- a/absl/flags/internal/flag.cc
+++ b/absl/flags/internal/flag.cc
@@ -62,14 +62,14 @@ bool ShouldValidateFlagValue(FlagFastTypeId flag_type_id) {
 // need to acquire these locks themselves.
 class MutexRelock {
  public:
-  explicit MutexRelock(absl::Mutex* mu) : mu_(mu) { mu_->Unlock(); }
-  ~MutexRelock() { mu_->Lock(); }
+  explicit MutexRelock(absl::Mutex& mu) : mu_(mu) { mu_.Unlock(); }
+  ~MutexRelock() { mu_.Lock(); }
 
   MutexRelock(const MutexRelock&) = delete;
   MutexRelock& operator=(const MutexRelock&) = delete;
 
  private:
-  absl::Mutex* mu_;
+  absl::Mutex& mu_;
 };
 
 }  // namespace
@@ -82,7 +82,7 @@ class FlagImpl;
 class FlagState : public flags_internal::FlagStateInterface {
  public:
   template <typename V>
-  FlagState(FlagImpl* flag_impl, const V& v, bool modified,
+  FlagState(FlagImpl& flag_impl, const V& v, bool modified,
             bool on_command_line, int64_t counter)
       : flag_impl_(flag_impl),
         value_(v),
@@ -91,9 +91,9 @@ class FlagState : public flags_internal::FlagStateInterface {
         counter_(counter) {}
 
   ~FlagState() override {
-    if (flag_impl_->ValueStorageKind() != FlagValueStorageKind::kAlignedBuffer)
+    if (flag_impl_.ValueStorageKind() != FlagValueStorageKind::kAlignedBuffer)
       return;
-    flags_internal::Delete(flag_impl_->op_, value_.heap_allocated);
+    flags_internal::Delete(flag_impl_.op_, value_.heap_allocated);
   }
 
  private:
@@ -101,15 +101,15 @@ class FlagState : public flags_internal::FlagStateInterface {
 
   // Restores the flag to the saved state.
   void Restore() const override {
-    if (!flag_impl_->RestoreState(*this)) return;
+    if (!flag_impl_.RestoreState(*this)) return;
 
-    ABSL_INTERNAL_LOG(
-        INFO, absl::StrCat("Restore saved value of ", flag_impl_->Name(),
-                           " to: ", flag_impl_->CurrentValue()));
+    ABSL_INTERNAL_LOG(INFO,
+                      absl::StrCat("Restore saved value of ", flag_impl_.Name(),
+                                   " to: ", flag_impl_.CurrentValue()));
   }
 
   // Flag and saved flag data.
-  FlagImpl* flag_impl_;
+  FlagImpl& flag_impl_;
   union SavedValue {
     explicit SavedValue(void* v) : heap_allocated(v) {}
     explicit SavedValue(int64_t v) : one_word(v) {}
@@ -326,7 +326,7 @@ void FlagImpl::InvokeCallback() const {
   // and it also can be different by the time the callback invocation is
   // completed. Requires that *primary_lock be held in exclusive mode; it may be
   // released and reacquired by the implementation.
-  MutexRelock relock(DataGuard());
+  MutexRelock relock(*DataGuard());
   absl::MutexLock lock(&callback_->guard);
   cb();
 }
@@ -339,17 +339,17 @@ std::unique_ptr<FlagStateInterface> FlagImpl::SaveState() {
   switch (ValueStorageKind()) {
     case FlagValueStorageKind::kAlignedBuffer: {
       return absl::make_unique<FlagState>(
-          this, flags_internal::Clone(op_, AlignedBufferValue()), modified,
+          *this, flags_internal::Clone(op_, AlignedBufferValue()), modified,
           on_command_line, counter_);
     }
     case FlagValueStorageKind::kOneWordAtomic: {
       return absl::make_unique<FlagState>(
-          this, OneWordValue().load(std::memory_order_acquire), modified,
+          *this, OneWordValue().load(std::memory_order_acquire), modified,
           on_command_line, counter_);
     }
     case FlagValueStorageKind::kTwoWordsAtomic: {
       return absl::make_unique<FlagState>(
-          this, TwoWordsValue().load(std::memory_order_acquire), modified,
+          *this, TwoWordsValue().load(std::memory_order_acquire), modified,
           on_command_line, counter_);
     }
   }
@@ -410,14 +410,14 @@ std::atomic<AlignedTwoWords>& FlagImpl::TwoWordsValue() const {
 // parsed value. In case if any error is encountered in either step, the error
 // message is stored in 'err'
 std::unique_ptr<void, DynValueDeleter> FlagImpl::TryParse(
-    absl::string_view value, std::string* err) const {
+    absl::string_view value, std::string& err) const {
   std::unique_ptr<void, DynValueDeleter> tentative_value = MakeInitValue();
 
   std::string parse_err;
   if (!flags_internal::Parse(op_, value, tentative_value.get(), &parse_err)) {
     absl::string_view err_sep = parse_err.empty() ? "" : "; ";
-    *err = absl::StrCat("Illegal value '", value, "' specified for flag '",
-                        Name(), "'", err_sep, parse_err);
+    err = absl::StrCat("Illegal value '", value, "' specified for flag '",
+                       Name(), "'", err_sep, parse_err);
     return nullptr;
   }
 
@@ -473,7 +473,7 @@ void FlagImpl::Write(const void* src) {
 //  * Update the current flag value if it was never set before
 // The mode is selected based on 'set_mode' parameter.
 bool FlagImpl::ParseFrom(absl::string_view value, FlagSettingMode set_mode,
-                         ValueSource source, std::string* err) {
+                         ValueSource source, std::string& err) {
   absl::MutexLock l(DataGuard());
 
   switch (set_mode) {
diff --git a/absl/flags/internal/flag.h b/absl/flags/internal/flag.h
index 97ddb5f9..e1885809 100644
--- a/absl/flags/internal/flag.h
+++ b/absl/flags/internal/flag.h
@@ -374,31 +374,31 @@ struct FlagValue;
 
 template <typename T>
 struct FlagValue<T, FlagValueStorageKind::kAlignedBuffer> {
-  bool Get(T*) const { return false; }
+  bool Get(T&) const { return false; }
 
   alignas(T) char value[sizeof(T)];
 };
 
 template <typename T>
 struct FlagValue<T, FlagValueStorageKind::kOneWordAtomic> : FlagOneWordValue {
-  bool Get(T* dst) const {
+  bool Get(T& dst) const {
     int64_t one_word_val = value.load(std::memory_order_acquire);
     if (ABSL_PREDICT_FALSE(one_word_val == UninitializedFlagValue())) {
       return false;
     }
-    std::memcpy(dst, static_cast<const void*>(&one_word_val), sizeof(T));
+    std::memcpy(&dst, static_cast<const void*>(&one_word_val), sizeof(T));
     return true;
   }
 };
 
 template <typename T>
 struct FlagValue<T, FlagValueStorageKind::kTwoWordsAtomic> : FlagTwoWordsValue {
-  bool Get(T* dst) const {
+  bool Get(T& dst) const {
     AlignedTwoWords two_words_val = value.load(std::memory_order_acquire);
     if (ABSL_PREDICT_FALSE(!two_words_val.IsInitialized())) {
       return false;
     }
-    std::memcpy(dst, static_cast<const void*>(&two_words_val), sizeof(T));
+    std::memcpy(&dst, static_cast<const void*>(&two_words_val), sizeof(T));
     return true;
   }
 };
@@ -502,7 +502,7 @@ class FlagImpl final : public CommandLineFlag {
   // Attempts to parse supplied `value` string. If parsing is successful,
   // returns new value. Otherwise returns nullptr.
   std::unique_ptr<void, DynValueDeleter> TryParse(absl::string_view value,
-                                                  std::string* err) const
+                                                  std::string& err) const
       ABSL_EXCLUSIVE_LOCKS_REQUIRED(*DataGuard());
   // Stores the flag value based on the pointer to the source.
   void StoreValue(const void* src) ABSL_EXCLUSIVE_LOCKS_REQUIRED(*DataGuard());
@@ -544,7 +544,7 @@ class FlagImpl final : public CommandLineFlag {
       ABSL_LOCKS_EXCLUDED(*DataGuard());
 
   bool ParseFrom(absl::string_view value, FlagSettingMode set_mode,
-                 ValueSource source, std::string* error) override
+                 ValueSource source, std::string& error) override
       ABSL_LOCKS_EXCLUDED(*DataGuard());
 
   // Immutable flag's state.
@@ -651,7 +651,7 @@ class Flag {
     impl_.AssertValidType(base_internal::FastTypeId<T>(), &GenRuntimeTypeId<T>);
 #endif
 
-    if (!value_.Get(&u.value)) impl_.Read(&u.value);
+    if (!value_.Get(u.value)) impl_.Read(&u.value);
     return std::move(u.value);
   }
   void Set(const T& v) {
@@ -730,12 +730,12 @@ struct FlagRegistrarEmpty {};
 template <typename T, bool do_register>
 class FlagRegistrar {
  public:
-  explicit FlagRegistrar(Flag<T>* flag) : flag_(flag) {
-    if (do_register) flags_internal::RegisterCommandLineFlag(&flag_->impl_);
+  explicit FlagRegistrar(Flag<T>& flag) : flag_(flag) {
+    if (do_register) flags_internal::RegisterCommandLineFlag(flag_.impl_);
   }
 
   FlagRegistrar OnUpdate(FlagCallbackFunc cb) && {
-    flag_->impl_.SetCallback(cb);
+    flag_.impl_.SetCallback(cb);
     return *this;
   }
 
@@ -745,7 +745,7 @@ class FlagRegistrar {
   operator FlagRegistrarEmpty() const { return {}; }  // NOLINT
 
  private:
-  Flag<T>* flag_;  // Flag being registered (not owned).
+  Flag<T>& flag_;  // Flag being registered (not owned).
 };
 
 }  // namespace flags_internal
diff --git a/absl/flags/internal/private_handle_accessor.cc b/absl/flags/internal/private_handle_accessor.cc
index 64fe3166..24b49136 100644
--- a/absl/flags/internal/private_handle_accessor.cc
+++ b/absl/flags/internal/private_handle_accessor.cc
@@ -24,8 +24,8 @@ FlagFastTypeId PrivateHandleAccessor::TypeId(const CommandLineFlag& flag) {
 }
 
 std::unique_ptr<FlagStateInterface> PrivateHandleAccessor::SaveState(
-    CommandLineFlag* flag) {
-  return flag->SaveState();
+    CommandLineFlag& flag) {
+  return flag.SaveState();
 }
 
 bool PrivateHandleAccessor::IsSpecifiedOnCommandLine(
@@ -43,12 +43,12 @@ void PrivateHandleAccessor::CheckDefaultValueParsingRoundtrip(
   flag.CheckDefaultValueParsingRoundtrip();
 }
 
-bool PrivateHandleAccessor::ParseFrom(CommandLineFlag* flag,
+bool PrivateHandleAccessor::ParseFrom(CommandLineFlag& flag,
                                       absl::string_view value,
                                       flags_internal::FlagSettingMode set_mode,
                                       flags_internal::ValueSource source,
-                                      std::string* error) {
-  return flag->ParseFrom(value, set_mode, source, error);
+                                      std::string& error) {
+  return flag.ParseFrom(value, set_mode, source, error);
 }
 
 }  // namespace flags_internal
diff --git a/absl/flags/internal/private_handle_accessor.h b/absl/flags/internal/private_handle_accessor.h
index 07838600..9a327a07 100644
--- a/absl/flags/internal/private_handle_accessor.h
+++ b/absl/flags/internal/private_handle_accessor.h
@@ -31,7 +31,7 @@ class PrivateHandleAccessor {
   static FlagFastTypeId TypeId(const CommandLineFlag& flag);
 
   // Access to CommandLineFlag::SaveState.
-  static std::unique_ptr<FlagStateInterface> SaveState(CommandLineFlag* flag);
+  static std::unique_ptr<FlagStateInterface> SaveState(CommandLineFlag& flag);
 
   // Access to CommandLineFlag::IsSpecifiedOnCommandLine.
   static bool IsSpecifiedOnCommandLine(const CommandLineFlag& flag);
@@ -43,9 +43,9 @@ class PrivateHandleAccessor {
   // Access to CommandLineFlag::CheckDefaultValueParsingRoundtrip.
   static void CheckDefaultValueParsingRoundtrip(const CommandLineFlag& flag);
 
-  static bool ParseFrom(CommandLineFlag* flag, absl::string_view value,
+  static bool ParseFrom(CommandLineFlag& flag, absl::string_view value,
                         flags_internal::FlagSettingMode set_mode,
-                        flags_internal::ValueSource source, std::string* error);
+                        flags_internal::ValueSource source, std::string& error);
 };
 
 }  // namespace flags_internal
diff --git a/absl/flags/internal/registry.cc b/absl/flags/internal/registry.cc
index 70d76557..4bcebfa9 100644
--- a/absl/flags/internal/registry.cc
+++ b/absl/flags/internal/registry.cc
@@ -60,8 +60,8 @@ class FlagRegistry {
   FlagRegistry() = default;
   ~FlagRegistry() = default;
 
-  // Store a flag in this registry.  Takes ownership of *flag.
-  void RegisterFlag(CommandLineFlag* flag);
+  // Store a flag in this registry. Takes ownership of *flag.
+  void RegisterFlag(CommandLineFlag& flag);
 
   void Lock() ABSL_EXCLUSIVE_LOCK_FUNCTION(lock_) { lock_.Lock(); }
   void Unlock() ABSL_UNLOCK_FUNCTION(lock_) { lock_.Unlock(); }
@@ -74,12 +74,12 @@ class FlagRegistry {
   // found or not retired.  Does not emit a warning.
   CommandLineFlag* FindRetiredFlagLocked(absl::string_view name);
 
-  static FlagRegistry* GlobalRegistry();  // returns a singleton registry
+  static FlagRegistry& GlobalRegistry();  // returns a singleton registry
 
  private:
   friend class FlagSaverImpl;  // reads all the flags in order to copy them
   friend void ForEachFlagUnlocked(
-      std::function<void(CommandLineFlag*)> visitor);
+      std::function<void(CommandLineFlag&)> visitor);
 
   // The map from name to flag, for FindFlagLocked().
   using FlagMap = std::map<absl::string_view, CommandLineFlag*>;
@@ -94,65 +94,62 @@ class FlagRegistry {
   FlagRegistry& operator=(const FlagRegistry&);
 };
 
-FlagRegistry* FlagRegistry::GlobalRegistry() {
+FlagRegistry& FlagRegistry::GlobalRegistry() {
   static FlagRegistry* global_registry = new FlagRegistry;
-  return global_registry;
+  return *global_registry;
 }
 
 namespace {
 
 class FlagRegistryLock {
  public:
-  explicit FlagRegistryLock(FlagRegistry* fr) : fr_(fr) { fr_->Lock(); }
-  ~FlagRegistryLock() { fr_->Unlock(); }
+  explicit FlagRegistryLock(FlagRegistry& fr) : fr_(fr) { fr_.Lock(); }
+  ~FlagRegistryLock() { fr_.Unlock(); }
 
  private:
-  FlagRegistry* const fr_;
+  FlagRegistry& fr_;
 };
 
-void DestroyRetiredFlag(CommandLineFlag* flag);
+void DestroyRetiredFlag(CommandLineFlag& flag);
 
 }  // namespace
 
-void FlagRegistry::RegisterFlag(CommandLineFlag* flag) {
-  FlagRegistryLock registry_lock(this);
+void FlagRegistry::RegisterFlag(CommandLineFlag& flag) {
+  FlagRegistryLock registry_lock(*this);
   std::pair<FlagIterator, bool> ins =
-      flags_.insert(FlagMap::value_type(flag->Name(), flag));
+      flags_.insert(FlagMap::value_type(flag.Name(), &flag));
   if (ins.second == false) {  // means the name was already in the map
-    CommandLineFlag* old_flag = ins.first->second;
-    if (flag->IsRetired() != old_flag->IsRetired()) {
+    CommandLineFlag& old_flag = *ins.first->second;
+    if (flag.IsRetired() != old_flag.IsRetired()) {
       // All registrations must agree on the 'retired' flag.
       flags_internal::ReportUsageError(
           absl::StrCat(
-              "Retired flag '", flag->Name(),
-              "' was defined normally in file '",
-              (flag->IsRetired() ? old_flag->Filename() : flag->Filename()),
-              "'."),
+              "Retired flag '", flag.Name(), "' was defined normally in file '",
+              (flag.IsRetired() ? old_flag.Filename() : flag.Filename()), "'."),
           true);
-    } else if (flags_internal::PrivateHandleAccessor::TypeId(*flag) !=
-               flags_internal::PrivateHandleAccessor::TypeId(*old_flag)) {
+    } else if (flags_internal::PrivateHandleAccessor::TypeId(flag) !=
+               flags_internal::PrivateHandleAccessor::TypeId(old_flag)) {
       flags_internal::ReportUsageError(
-          absl::StrCat("Flag '", flag->Name(),
+          absl::StrCat("Flag '", flag.Name(),
                        "' was defined more than once but with "
                        "differing types. Defined in files '",
-                       old_flag->Filename(), "' and '", flag->Filename(), "'."),
+                       old_flag.Filename(), "' and '", flag.Filename(), "'."),
           true);
-    } else if (old_flag->IsRetired()) {
+    } else if (old_flag.IsRetired()) {
       // Retired flag can just be deleted.
       DestroyRetiredFlag(flag);
       return;
-    } else if (old_flag->Filename() != flag->Filename()) {
+    } else if (old_flag.Filename() != flag.Filename()) {
       flags_internal::ReportUsageError(
-          absl::StrCat("Flag '", flag->Name(),
+          absl::StrCat("Flag '", flag.Name(),
                        "' was defined more than once (in files '",
-                       old_flag->Filename(), "' and '", flag->Filename(),
-                       "')."),
+                       old_flag.Filename(), "' and '", flag.Filename(), "')."),
           true);
     } else {
       flags_internal::ReportUsageError(
           absl::StrCat(
-              "Something wrong with flag '", flag->Name(), "' in file '",
-              flag->Filename(), "'. One possibility: file '", flag->Filename(),
+              "Something wrong with flag '", flag.Name(), "' in file '",
+              flag.Filename(), "'. One possibility: file '", flag.Filename(),
               "' is being linked both statically and dynamically into this "
               "executable. e.g. some files listed as srcs to a test and also "
               "listed as srcs of some shared lib deps of the same test."),
@@ -206,7 +203,7 @@ class FlagSaverImpl {
   // It's an error to call this more than once.
   void SaveFromRegistry() {
     assert(backup_registry_.empty());  // call only once!
-    flags_internal::ForEachFlag([&](CommandLineFlag* flag) {
+    flags_internal::ForEachFlag([&](CommandLineFlag& flag) {
       if (auto flag_state =
               flags_internal::PrivateHandleAccessor::SaveState(flag)) {
         backup_registry_.emplace_back(std::move(flag_state));
@@ -244,39 +241,39 @@ FlagSaver::~FlagSaver() {
 
 CommandLineFlag* FindCommandLineFlag(absl::string_view name) {
   if (name.empty()) return nullptr;
-  FlagRegistry* const registry = FlagRegistry::GlobalRegistry();
+  FlagRegistry& registry = FlagRegistry::GlobalRegistry();
   FlagRegistryLock frl(registry);
 
-  return registry->FindFlagLocked(name);
+  return registry.FindFlagLocked(name);
 }
 
 CommandLineFlag* FindRetiredFlag(absl::string_view name) {
-  FlagRegistry* const registry = FlagRegistry::GlobalRegistry();
+  FlagRegistry& registry = FlagRegistry::GlobalRegistry();
   FlagRegistryLock frl(registry);
 
-  return registry->FindRetiredFlagLocked(name);
+  return registry.FindRetiredFlagLocked(name);
 }
 
 // --------------------------------------------------------------------
 
-void ForEachFlagUnlocked(std::function<void(CommandLineFlag*)> visitor) {
-  FlagRegistry* const registry = FlagRegistry::GlobalRegistry();
-  for (FlagRegistry::FlagConstIterator i = registry->flags_.begin();
-       i != registry->flags_.end(); ++i) {
-    visitor(i->second);
+void ForEachFlagUnlocked(std::function<void(CommandLineFlag&)> visitor) {
+  FlagRegistry& registry = FlagRegistry::GlobalRegistry();
+  for (FlagRegistry::FlagConstIterator i = registry.flags_.begin();
+       i != registry.flags_.end(); ++i) {
+    visitor(*i->second);
   }
 }
 
-void ForEachFlag(std::function<void(CommandLineFlag*)> visitor) {
-  FlagRegistry* const registry = FlagRegistry::GlobalRegistry();
+void ForEachFlag(std::function<void(CommandLineFlag&)> visitor) {
+  FlagRegistry& registry = FlagRegistry::GlobalRegistry();
   FlagRegistryLock frl(registry);
   ForEachFlagUnlocked(visitor);
 }
 
 // --------------------------------------------------------------------
 
-bool RegisterCommandLineFlag(CommandLineFlag* flag) {
-  FlagRegistry::GlobalRegistry()->RegisterFlag(flag);
+bool RegisterCommandLineFlag(CommandLineFlag& flag) {
+  FlagRegistry::GlobalRegistry().RegisterFlag(flag);
   return true;
 }
 
@@ -307,7 +304,7 @@ class RetiredFlagObj final : public CommandLineFlag {
   }
 
   bool ParseFrom(absl::string_view, flags_internal::FlagSettingMode,
-                 flags_internal::ValueSource, std::string*) override {
+                 flags_internal::ValueSource, std::string&) override {
     return false;
   }
 
@@ -320,16 +317,16 @@ class RetiredFlagObj final : public CommandLineFlag {
   const FlagFastTypeId type_id_;
 };
 
-void DestroyRetiredFlag(CommandLineFlag* flag) {
-  assert(flag->IsRetired());
-  delete static_cast<RetiredFlagObj*>(flag);
+void DestroyRetiredFlag(CommandLineFlag& flag) {
+  assert(flag.IsRetired());
+  delete static_cast<RetiredFlagObj*>(&flag);
 }
 
 }  // namespace
 
 bool Retire(const char* name, FlagFastTypeId type_id) {
   auto* flag = new flags_internal::RetiredFlagObj(name, type_id);
-  FlagRegistry::GlobalRegistry()->RegisterFlag(flag);
+  FlagRegistry::GlobalRegistry().RegisterFlag(*flag);
   return true;
 }
 
diff --git a/absl/flags/internal/registry.h b/absl/flags/internal/registry.h
index f722fd44..a118865a 100644
--- a/absl/flags/internal/registry.h
+++ b/absl/flags/internal/registry.h
@@ -39,14 +39,14 @@ CommandLineFlag* FindRetiredFlag(absl::string_view name);
 
 // Executes specified visitor for each non-retired flag in the registry.
 // Requires the caller hold the registry lock.
-void ForEachFlagUnlocked(std::function<void(CommandLineFlag*)> visitor);
+void ForEachFlagUnlocked(std::function<void(CommandLineFlag&)> visitor);
 // Executes specified visitor for each non-retired flag in the registry. While
 // callback are executed, the registry is locked and can't be changed.
-void ForEachFlag(std::function<void(CommandLineFlag*)> visitor);
+void ForEachFlag(std::function<void(CommandLineFlag&)> visitor);
 
 //-----------------------------------------------------------------------------
 
-bool RegisterCommandLineFlag(CommandLineFlag*);
+bool RegisterCommandLineFlag(CommandLineFlag&);
 
 //-----------------------------------------------------------------------------
 // Retired registrations:
diff --git a/absl/flags/internal/type_erased.cc b/absl/flags/internal/type_erased.cc
index 35b0d125..b2523b24 100644
--- a/absl/flags/internal/type_erased.cc
+++ b/absl/flags/internal/type_erased.cc
@@ -58,7 +58,7 @@ bool SetCommandLineOptionWithMode(absl::string_view name,
 
   std::string error;
   if (!flags_internal::PrivateHandleAccessor::ParseFrom(
-          flag, value, set_mode, kProgrammaticChange, &error)) {
+          *flag, value, set_mode, kProgrammaticChange, error)) {
     // Errors here are all of the form: the provided name was a recognized
     // flag, but the value was invalid (bad type, or validation failed).
     flags_internal::ReportUsageError(error, false);
diff --git a/absl/flags/internal/usage.cc b/absl/flags/internal/usage.cc
index 11664e10..2a2231a7 100644
--- a/absl/flags/internal/usage.cc
+++ b/absl/flags/internal/usage.cc
@@ -107,8 +107,8 @@ class FlagHelpPrettyPrinter {
  public:
   // Pretty printer holds on to the std::ostream& reference to direct an output
   // to that stream.
-  FlagHelpPrettyPrinter(int max_line_len, std::ostream* out)
-      : out_(*out),
+  FlagHelpPrettyPrinter(int max_line_len, std::ostream& out)
+      : out_(out),
         max_line_len_(max_line_len),
         line_len_(0),
         first_line_(true) {}
@@ -182,7 +182,7 @@ class FlagHelpPrettyPrinter {
   bool first_line_;
 };
 
-void FlagHelpHumanReadable(const CommandLineFlag& flag, std::ostream* out) {
+void FlagHelpHumanReadable(const CommandLineFlag& flag, std::ostream& out) {
   FlagHelpPrettyPrinter printer(80, out);  // Max line length is 80.
 
   // Flag name.
@@ -244,29 +244,28 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
   // This map is used to output matching flags grouped by package and file
   // name.
   std::map<std::string,
-           std::map<std::string, std::vector<const CommandLineFlag*>>>
+           std::map<std::string, std::vector<const absl::CommandLineFlag*>>>
       matching_flags;
 
-  flags_internal::ForEachFlag([&](CommandLineFlag* flag) {
-    std::string flag_filename = flag->Filename();
+  flags_internal::ForEachFlag([&](absl::CommandLineFlag& flag) {
+    std::string flag_filename = flag.Filename();
 
     // Ignore retired flags.
-    if (flag->IsRetired()) return;
+    if (flag.IsRetired()) return;
 
     // If the flag has been stripped, pretend that it doesn't exist.
-    if (flag->Help() == flags_internal::kStrippedFlagHelp) return;
+    if (flag.Help() == flags_internal::kStrippedFlagHelp) return;
 
     // Make sure flag satisfies the filter
     if (!filter_cb || !filter_cb(flag_filename)) return;
 
     matching_flags[std::string(flags_internal::Package(flag_filename))]
                   [flag_filename]
-                      .push_back(flag);
+                      .push_back(&flag);
   });
 
-  absl::string_view
-      package_separator;             // controls blank lines between packages.
-  absl::string_view file_separator;  // controls blank lines between files.
+  absl::string_view package_separator;  // controls blank lines between packages
+  absl::string_view file_separator;     // controls blank lines between files
   for (const auto& package : matching_flags) {
     if (format == HelpFormat::kHumanReadable) {
       out << package_separator;
@@ -304,7 +303,7 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
 void FlagHelp(std::ostream& out, const CommandLineFlag& flag,
               HelpFormat format) {
   if (format == HelpFormat::kHumanReadable)
-    flags_internal::FlagHelpHumanReadable(flag, &out);
+    flags_internal::FlagHelpHumanReadable(flag, out);
 }
 
 // --------------------------------------------------------------------
diff --git a/absl/flags/marshalling.cc b/absl/flags/marshalling.cc
index 09baae88..81f9cebd 100644
--- a/absl/flags/marshalling.cc
+++ b/absl/flags/marshalling.cc
@@ -74,15 +74,16 @@ static int NumericBase(absl::string_view text) {
 }
 
 template <typename IntType>
-inline bool ParseFlagImpl(absl::string_view text, IntType* dst) {
+inline bool ParseFlagImpl(absl::string_view text, IntType& dst) {
   text = absl::StripAsciiWhitespace(text);
 
-  return absl::numbers_internal::safe_strtoi_base(text, dst, NumericBase(text));
+  return absl::numbers_internal::safe_strtoi_base(text, &dst,
+                                                  NumericBase(text));
 }
 
 bool AbslParseFlag(absl::string_view text, short* dst, std::string*) {
   int val;
-  if (!ParseFlagImpl(text, &val)) return false;
+  if (!ParseFlagImpl(text, val)) return false;
   if (static_cast<short>(val) != val)  // worked, but number out of range
     return false;
   *dst = static_cast<short>(val);
@@ -91,7 +92,7 @@ bool AbslParseFlag(absl::string_view text, short* dst, std::string*) {
 
 bool AbslParseFlag(absl::string_view text, unsigned short* dst, std::string*) {
   unsigned int val;
-  if (!ParseFlagImpl(text, &val)) return false;
+  if (!ParseFlagImpl(text, val)) return false;
   if (static_cast<unsigned short>(val) !=
       val)  // worked, but number out of range
     return false;
@@ -100,28 +101,28 @@ bool AbslParseFlag(absl::string_view text, unsigned short* dst, std::string*) {
 }
 
 bool AbslParseFlag(absl::string_view text, int* dst, std::string*) {
-  return ParseFlagImpl(text, dst);
+  return ParseFlagImpl(text, *dst);
 }
 
 bool AbslParseFlag(absl::string_view text, unsigned int* dst, std::string*) {
-  return ParseFlagImpl(text, dst);
+  return ParseFlagImpl(text, *dst);
 }
 
 bool AbslParseFlag(absl::string_view text, long* dst, std::string*) {
-  return ParseFlagImpl(text, dst);
+  return ParseFlagImpl(text, *dst);
 }
 
 bool AbslParseFlag(absl::string_view text, unsigned long* dst, std::string*) {
-  return ParseFlagImpl(text, dst);
+  return ParseFlagImpl(text, *dst);
 }
 
 bool AbslParseFlag(absl::string_view text, long long* dst, std::string*) {
-  return ParseFlagImpl(text, dst);
+  return ParseFlagImpl(text, *dst);
 }
 
 bool AbslParseFlag(absl::string_view text, unsigned long long* dst,
                    std::string*) {
-  return ParseFlagImpl(text, dst);
+  return ParseFlagImpl(text, *dst);
 }
 
 // --------------------------------------------------------------------
diff --git a/absl/flags/parse.cc b/absl/flags/parse.cc
index 3f0a7a75..15300786 100644
--- a/absl/flags/parse.cc
+++ b/absl/flags/parse.cc
@@ -222,7 +222,7 @@ bool ArgsList::ReadFromFlagfile(const std::string& flag_file_name) {
 // Reads the environment variable with name `name` and stores results in
 // `value`. If variable is not present in environment returns false, otherwise
 // returns true.
-bool GetEnvVar(const char* var_name, std::string* var_value) {
+bool GetEnvVar(const char* var_name, std::string& var_value) {
 #ifdef _WIN32
   char buf[1024];
   auto get_res = GetEnvironmentVariableA(var_name, buf, sizeof(buf));
@@ -234,14 +234,14 @@ bool GetEnvVar(const char* var_name, std::string* var_value) {
     return false;
   }
 
-  *var_value = std::string(buf, get_res);
+  var_value = std::string(buf, get_res);
 #else
   const char* val = ::getenv(var_name);
   if (val == nullptr) {
     return false;
   }
 
-  *var_value = val;
+  var_value = val;
 #endif
 
   return true;
@@ -306,17 +306,17 @@ std::tuple<CommandLineFlag*, bool> LocateFlag(absl::string_view flag_name) {
 // back.
 void CheckDefaultValuesParsingRoundtrip() {
 #ifndef NDEBUG
-  flags_internal::ForEachFlag([&](CommandLineFlag* flag) {
-    if (flag->IsRetired()) return;
+  flags_internal::ForEachFlag([&](CommandLineFlag& flag) {
+    if (flag.IsRetired()) return;
 
 #define ABSL_FLAGS_INTERNAL_IGNORE_TYPE(T, _) \
-  if (flag->IsOfType<T>()) return;
+  if (flag.IsOfType<T>()) return;
 
     ABSL_FLAGS_INTERNAL_SUPPORTED_TYPES(ABSL_FLAGS_INTERNAL_IGNORE_TYPE)
 #undef ABSL_FLAGS_INTERNAL_IGNORE_TYPE
 
     flags_internal::PrivateHandleAccessor::CheckDefaultValueParsingRoundtrip(
-        *flag);
+        flag);
   });
 #endif
 }
@@ -329,13 +329,13 @@ void CheckDefaultValuesParsingRoundtrip() {
 // the first flagfile in the input list are processed before the second flagfile
 // etc.
 bool ReadFlagfiles(const std::vector<std::string>& flagfiles,
-                   std::vector<ArgsList>* input_args) {
+                   std::vector<ArgsList>& input_args) {
   bool success = true;
   for (auto it = flagfiles.rbegin(); it != flagfiles.rend(); ++it) {
     ArgsList al;
 
     if (al.ReadFromFlagfile(*it)) {
-      input_args->push_back(al);
+      input_args.push_back(al);
     } else {
       success = false;
     }
@@ -350,7 +350,7 @@ bool ReadFlagfiles(const std::vector<std::string>& flagfiles,
 // `flag_name` is a string from the input flag_names list. If successful we
 // append a single ArgList at the end of the input_args.
 bool ReadFlagsFromEnv(const std::vector<std::string>& flag_names,
-                      std::vector<ArgsList>* input_args,
+                      std::vector<ArgsList>& input_args,
                       bool fail_on_absent_in_env) {
   bool success = true;
   std::vector<std::string> args;
@@ -371,7 +371,7 @@ bool ReadFlagsFromEnv(const std::vector<std::string>& flag_names,
 
     const std::string envname = absl::StrCat("FLAGS_", flag_name);
     std::string envval;
-    if (!GetEnvVar(envname.c_str(), &envval)) {
+    if (!GetEnvVar(envname.c_str(), envval)) {
       if (fail_on_absent_in_env) {
         flags_internal::ReportUsageError(
             absl::StrCat(envname, " not found in environment"), true);
@@ -386,7 +386,7 @@ bool ReadFlagsFromEnv(const std::vector<std::string>& flag_names,
   }
 
   if (success) {
-    input_args->emplace_back(args);
+    input_args.emplace_back(args);
   }
 
   return success;
@@ -396,8 +396,8 @@ bool ReadFlagsFromEnv(const std::vector<std::string>& flag_names,
 
 // Returns success status, which is true if were able to handle all generator
 // flags (flagfile, fromenv, tryfromemv) successfully.
-bool HandleGeneratorFlags(std::vector<ArgsList>* input_args,
-                          std::vector<std::string>* flagfile_value) {
+bool HandleGeneratorFlags(std::vector<ArgsList>& input_args,
+                          std::vector<std::string>& flagfile_value) {
   bool success = true;
 
   absl::MutexLock l(&flags_internal::processing_checks_guard);
@@ -422,9 +422,9 @@ bool HandleGeneratorFlags(std::vector<ArgsList>* input_args,
   if (flags_internal::flagfile_needs_processing) {
     auto flagfiles = absl::GetFlag(FLAGS_flagfile);
 
-    if (input_args->size() == 1) {
-      flagfile_value->insert(flagfile_value->end(), flagfiles.begin(),
-                             flagfiles.end());
+    if (input_args.size() == 1) {
+      flagfile_value.insert(flagfile_value.end(), flagfiles.begin(),
+                            flagfiles.end());
     }
 
     success &= ReadFlagfiles(flagfiles, input_args);
@@ -647,7 +647,7 @@ std::vector<char*> ParseCommandLineImpl(int argc, char* argv[],
   bool success = true;
   while (!input_args.empty()) {
     // 10. First we process the built-in generator flags.
-    success &= HandleGeneratorFlags(&input_args, &flagfile_value);
+    success &= HandleGeneratorFlags(input_args, flagfile_value);
 
     // 30. Select top-most (most recent) arguments list. If it is empty drop it
     // and re-try.
@@ -733,7 +733,7 @@ std::vector<char*> ParseCommandLineImpl(int argc, char* argv[],
 
     std::string error;
     if (!flags_internal::PrivateHandleAccessor::ParseFrom(
-            flag, value, SET_FLAGS_VALUE, kCommandLine, &error)) {
+            *flag, value, SET_FLAGS_VALUE, kCommandLine, error)) {
       flags_internal::ReportUsageError(error, true);
       success = false;
     } else {
diff --git a/absl/flags/parse_test.cc b/absl/flags/parse_test.cc
index e6a53ae6..aea068ee 100644
--- a/absl/flags/parse_test.cc
+++ b/absl/flags/parse_test.cc
@@ -171,8 +171,8 @@ constexpr const char* const ff2_data[] = {
 // temporary directory location. This way we can test inclusion of one flagfile
 // from another flagfile.
 const char* GetFlagfileFlag(const std::vector<FlagfileData>& ffd,
-                            std::string* flagfile_flag) {
-  *flagfile_flag = "--flagfile=";
+                            std::string& flagfile_flag) {
+  flagfile_flag = "--flagfile=";
   absl::string_view separator;
   for (const auto& flagfile_data : ffd) {
     std::string flagfile_name =
@@ -183,11 +183,11 @@ const char* GetFlagfileFlag(const std::vector<FlagfileData>& ffd,
       flagfile_out << absl::Substitute(line, GetTestTempDir()) << "\n";
     }
 
-    absl::StrAppend(flagfile_flag, separator, flagfile_name);
+    absl::StrAppend(&flagfile_flag, separator, flagfile_name);
     separator = ",";
   }
 
-  return flagfile_flag->c_str();
+  return flagfile_flag.c_str();
 }
 
 }  // namespace
@@ -588,14 +588,14 @@ TEST_F(ParseTest, TestSimpleValidFlagfile) {
   const char* in_args1[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff1", absl::MakeConstSpan(ff1_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
   };
   TestParse(in_args1, -1, 0.1, "q2w2  ", true);
 
   const char* in_args2[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff2", absl::MakeConstSpan(ff2_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
   };
   TestParse(in_args2, 100, 0.1, "q2w2  ", false);
 }
@@ -609,7 +609,7 @@ TEST_F(ParseTest, TestValidMultiFlagfile) {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff2", absl::MakeConstSpan(ff2_data)},
                        {"parse_test.ff1", absl::MakeConstSpan(ff1_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
   };
   TestParse(in_args1, -1, 0.1, "q2w2  ", true);
 }
@@ -622,7 +622,7 @@ TEST_F(ParseTest, TestFlagfileMixedWithRegularFlags) {
   const char* in_args1[] = {
       "testbin", "--int_flag=3",
       GetFlagfileFlag({{"parse_test.ff1", absl::MakeConstSpan(ff1_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
       "-double_flag=0.2"};
   TestParse(in_args1, -1, 0.2, "q2w2  ", true);
 }
@@ -640,7 +640,7 @@ TEST_F(ParseTest, TestFlagfileInFlagfile) {
   const char* in_args1[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff3", absl::MakeConstSpan(ff3_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
   };
   TestParse(in_args1, 100, 0.1, "q2w2  ", false);
 }
@@ -657,7 +657,7 @@ TEST_F(ParseDeathTest, TestInvalidFlagfiles) {
   const char* in_args1[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff4",
-                        absl::MakeConstSpan(ff4_data)}}, &flagfile_flag),
+                        absl::MakeConstSpan(ff4_data)}}, flagfile_flag),
   };
   EXPECT_DEATH_IF_SUPPORTED(InvokeParse(in_args1),
                "Unknown command line flag 'unknown_flag'");
@@ -669,7 +669,7 @@ TEST_F(ParseDeathTest, TestInvalidFlagfiles) {
   const char* in_args2[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff5",
-                        absl::MakeConstSpan(ff5_data)}}, &flagfile_flag),
+                        absl::MakeConstSpan(ff5_data)}}, flagfile_flag),
   };
   EXPECT_DEATH_IF_SUPPORTED(InvokeParse(in_args2),
                "Unknown command line flag 'int_flag 10'");
@@ -681,7 +681,7 @@ TEST_F(ParseDeathTest, TestInvalidFlagfiles) {
   const char* in_args3[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff6", absl::MakeConstSpan(ff6_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
   };
   EXPECT_DEATH_IF_SUPPORTED(InvokeParse(in_args3),
                "Flagfile can't contain position arguments or --");
@@ -702,7 +702,7 @@ TEST_F(ParseDeathTest, TestInvalidFlagfiles) {
   const char* in_args5[] = {
       "testbin",
       GetFlagfileFlag({{"parse_test.ff7", absl::MakeConstSpan(ff7_data)}},
-                      &flagfile_flag),
+                      flagfile_flag),
   };
   EXPECT_DEATH_IF_SUPPORTED(InvokeParse(in_args5),
                "Unexpected line in the flagfile .*: \\*bin\\*");