Export of internal Abseil changes

--
972333fe1e43427849b8a634aa35061e81be3642 by Abseil Team <absl-team@google.com>:

Replace deprecated thread annotations macros.

PiperOrigin-RevId: 267332619

--
7039c6dc499a31c372b4872eda0772455931c360 by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 267220271

--
a3f524d2afc2535686f206a7ce06961016349d7a by Abseil Team <absl-team@google.com>:

Factor kernel_timeout out of synchronization.

PiperOrigin-RevId: 267217304

--
90287de4114ef9a06cafe50256a2d03349772c21 by Abseil Team <absl-team@google.com>:

Fixed comment typo.

PiperOrigin-RevId: 267198532

--
d312c1a1e52aeca1871ff0deead416d09a7f237e by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 267185804
GitOrigin-RevId: 972333fe1e43427849b8a634aa35061e81be3642
Change-Id: Ia8a2f877c57cef9854aad48f1753af872fc04dc8

12 files changed, 159 insertions, 282 deletions

diff --git a/absl/flags/internal/commandlineflag.cc b/absl/flags/internal/commandlineflag.cc
index 2063cda6..ae6a8d70 100644
--- a/absl/flags/internal/commandlineflag.cc
+++ b/absl/flags/internal/commandlineflag.cc
@@ -58,55 +58,55 @@ absl::Mutex* InitFlag(CommandLineFlag* flag) {
   {
     absl::MutexLock lock(&init_lock);
 
-    if (flag->locks == nullptr) {  // Must initialize Mutexes for this flag.
-      flag->locks = new flags_internal::CommandLineFlagLocks;
+    if (flag->locks_ == nullptr) {  // Must initialize Mutexes for this flag.
+      flag->locks_ = new flags_internal::CommandLineFlagLocks;
     }
 
-    mu = &flag->locks->primary_mu;
+    mu = &flag->locks_->primary_mu;
   }
 
   {
     absl::MutexLock lock(mu);
 
-    if (!flag->IsRetired() && flag->def == nullptr) {
+    if (!flag->IsRetired() && flag->def_ == nullptr) {
       // Need to initialize def and cur fields.
-      flag->def = (*flag->make_init_value)();
-      flag->cur = Clone(flag->op, flag->def);
+      flag->def_ = (*flag->make_init_value_)();
+      flag->cur_ = Clone(flag->op_, flag->def_);
       UpdateCopy(flag);
-      flag->inited.store(true, std::memory_order_release);
+      flag->inited_.store(true, std::memory_order_release);
       flag->InvokeCallback();
     }
   }
 
-  flag->inited.store(true, std::memory_order_release);
+  flag->inited_.store(true, std::memory_order_release);
   return mu;
 }
 
 // Ensure that the lazily initialized fields of *flag have been initialized,
-// and return &flag->locks->primary_mu.
+// and return &flag->locks_->primary_mu.
 absl::Mutex* CommandLineFlag::InitFlagIfNecessary() const
-    LOCK_RETURNED(locks->primary_mu) {
-  if (!this->inited.load(std::memory_order_acquire)) {
+    ABSL_LOCK_RETURNED(locks_->primary_mu) {
+  if (!inited_.load(std::memory_order_acquire)) {
     return InitFlag(const_cast<CommandLineFlag*>(this));
   }
 
-  // All fields initialized; this->locks is therefore safe to read.
-  return &this->locks->primary_mu;
+  // All fields initialized; locks_ is therefore safe to read.
+  return &locks_->primary_mu;
 }
 
 bool CommandLineFlag::IsModified() const {
   absl::MutexLock l(InitFlagIfNecessary());
-  return modified;
+  return modified_;
 }
 
 void CommandLineFlag::SetModified(bool is_modified) {
   absl::MutexLock l(InitFlagIfNecessary());
-  modified = is_modified;
+  modified_ = is_modified;
 }
 
 bool CommandLineFlag::IsSpecifiedOnCommandLine() const {
   absl::MutexLock l(InitFlagIfNecessary());
-  return on_command_line;
+  return on_command_line_;
 }
 
 absl::string_view CommandLineFlag::Typename() const {
@@ -134,19 +134,19 @@ absl::string_view CommandLineFlag::Typename() const {
 }
 
 std::string CommandLineFlag::Filename() const {
-  return flags_internal::GetUsageConfig().normalize_filename(this->filename);
+  return flags_internal::GetUsageConfig().normalize_filename(filename_);
 }
 
 std::string CommandLineFlag::DefaultValue() const {
   absl::MutexLock l(InitFlagIfNecessary());
 
-  return Unparse(this->marshalling_op, this->def);
+  return Unparse(marshalling_op_, def_);
 }
 
 std::string CommandLineFlag::CurrentValue() const {
   absl::MutexLock l(InitFlagIfNecessary());
 
-  return Unparse(this->marshalling_op, this->cur);
+  return Unparse(marshalling_op_, cur_);
 }
 
 // Attempts to parse supplied `value` string using parsing routine in the `flag`
@@ -157,31 +157,31 @@ std::string CommandLineFlag::CurrentValue() const {
 // in 'err'
 bool TryParseLocked(CommandLineFlag* flag, void* dst, absl::string_view value,
                     std::string* err)
-    EXCLUSIVE_LOCKS_REQUIRED(flag->locks->primary_mu) {
-  void* tentative_value = Clone(flag->op, flag->def);
+    ABSL_EXCLUSIVE_LOCKS_REQUIRED(flag->locks_->primary_mu) {
+  void* tentative_value = Clone(flag->op_, flag->def_);
   std::string parse_err;
-  if (!Parse(flag->marshalling_op, value, tentative_value, &parse_err)) {
+  if (!Parse(flag->marshalling_op_, value, tentative_value, &parse_err)) {
     auto type_name = flag->Typename();
     absl::string_view err_sep = parse_err.empty() ? "" : "; ";
     absl::string_view typename_sep = type_name.empty() ? "" : " ";
     *err = absl::StrCat("Illegal value '", value, "' specified for",
                         typename_sep, type_name, " flag '", flag->Name(), "'",
                         err_sep, parse_err);
-    Delete(flag->op, tentative_value);
+    Delete(flag->op_, tentative_value);
     return false;
   }
 
   if (!flag->InvokeValidator(tentative_value)) {
     *err = absl::StrCat("Failed validation of new value '",
-                        Unparse(flag->marshalling_op, tentative_value),
+                        Unparse(flag->marshalling_op_, tentative_value),
                         "' for flag '", flag->Name(), "'");
-    Delete(flag->op, tentative_value);
+    Delete(flag->op_, tentative_value);
     return false;
   }
 
-  flag->counter++;
-  Copy(flag->op, tentative_value, dst);
-  Delete(flag->op, tentative_value);
+  flag->counter_++;
+  Copy(flag->op_, tentative_value, dst);
+  Delete(flag->op_, tentative_value);
   return true;
 }
 
@@ -201,38 +201,38 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
   absl::MutexLock l(InitFlagIfNecessary());
 
   // Direct-access flags can be modified without going through the
-  // flag API. Detect such changes and update the flag->modified bit.
+  // flag API. Detect such changes and update the flag->modified_ bit.
   if (!IsAbseilFlag()) {
-    if (!this->modified && ChangedDirectly(this, this->cur, this->def)) {
-      this->modified = true;
+    if (!modified_ && ChangedDirectly(this, cur_, def_)) {
+      modified_ = true;
     }
   }
 
   switch (set_mode) {
     case SET_FLAGS_VALUE: {
       // set or modify the flag's value
-      if (!TryParseLocked(this, this->cur, value, err)) return false;
-      this->modified = true;
+      if (!TryParseLocked(this, cur_, value, err)) return false;
+      modified_ = true;
       UpdateCopy(this);
       InvokeCallback();
 
       if (source == kCommandLine) {
-        this->on_command_line = true;
+        on_command_line_ = true;
       }
       break;
     }
     case SET_FLAG_IF_DEFAULT: {
       // set the flag's value, but only if it hasn't been set by someone else
-      if (!this->modified) {
-        if (!TryParseLocked(this, this->cur, value, err)) return false;
-        this->modified = true;
+      if (!modified_) {
+        if (!TryParseLocked(this, cur_, value, err)) return false;
+        modified_ = true;
         UpdateCopy(this);
         InvokeCallback();
       } else {
         // TODO(rogeeff): review and fix this semantic. Currently we do not fail
         // in this case if flag is modified. This is misleading since the flag's
         // value is not updated even though we return true.
-        // *err = absl::StrCat(this->Name(), " is already set to ",
+        // *err = absl::StrCat(Name(), " is already set to ",
         //                     CurrentValue(), "\n");
         // return false;
         return true;
@@ -241,11 +241,11 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
     }
     case SET_FLAGS_DEFAULT: {
       // modify the flag's default-value
-      if (!TryParseLocked(this, this->def, value, err)) return false;
+      if (!TryParseLocked(this, def_, value, err)) return false;
 
-      if (!this->modified) {
+      if (!modified_) {
         // Need to set both defvalue *and* current, in this case
-        Copy(this->op, this->def, this->cur);
+        Copy(op_, def_, cur_);
         UpdateCopy(this);
         InvokeCallback();
       }
@@ -264,8 +264,8 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
 void CommandLineFlag::StoreAtomic(size_t size) {
   int64_t t = 0;
   assert(size <= sizeof(int64_t));
-  memcpy(&t, this->cur, size);
-  this->atomic.store(t, std::memory_order_release);
+  memcpy(&t, cur_, size);
+  atomic_.store(t, std::memory_order_release);
 }
 
 void CommandLineFlag::CheckDefaultValueParsingRoundtrip() const {
@@ -273,9 +273,9 @@ void CommandLineFlag::CheckDefaultValueParsingRoundtrip() const {
 
   absl::MutexLock lock(InitFlagIfNecessary());
 
-  void* dst = Clone(this->op, this->def);
+  void* dst = Clone(op_, def_);
   std::string error;
-  if (!flags_internal::Parse(this->marshalling_op, v, dst, &error)) {
+  if (!flags_internal::Parse(marshalling_op_, v, dst, &error)) {
     ABSL_INTERNAL_LOG(
         FATAL,
         absl::StrCat("Flag ", Name(), " (from ", Filename(),
@@ -285,23 +285,23 @@ void CommandLineFlag::CheckDefaultValueParsingRoundtrip() const {
 
   // We do not compare dst to def since parsing/unparsing may make
   // small changes, e.g., precision loss for floating point types.
-  Delete(this->op, dst);
+  Delete(op_, dst);
 }
 
 bool CommandLineFlag::ValidateDefaultValue() const {
   absl::MutexLock lock(InitFlagIfNecessary());
-  return InvokeValidator(this->def);
+  return InvokeValidator(def_);
 }
 
 bool CommandLineFlag::ValidateInputValue(absl::string_view value) const {
   absl::MutexLock l(InitFlagIfNecessary());  // protect default value access
 
-  void* obj = Clone(this->op, this->def);
+  void* obj = Clone(op_, def_);
   std::string ignored_error;
   const bool result =
-      flags_internal::Parse(this->marshalling_op, value, obj, &ignored_error) &&
+      flags_internal::Parse(marshalling_op_, value, obj, &ignored_error) &&
       InvokeValidator(obj);
-  Delete(this->op, obj);
+  Delete(op_, obj);
   return result;
 }
 
@@ -314,13 +314,13 @@ void CommandLineFlag::Read(void* dst,
   // `dst_op` is the unmarshaling operation corresponding to the declaration
   // visibile at the call site. `op` is the Flag's defined unmarshalling
   // operation. They must match for this operation to be well-defined.
-  if (ABSL_PREDICT_FALSE(dst_op != op)) {
+  if (ABSL_PREDICT_FALSE(dst_op != op_)) {
     ABSL_INTERNAL_LOG(
         ERROR,
-        absl::StrCat("Flag '", name,
+        absl::StrCat("Flag '", Name(),
                      "' is defined as one type and declared as another"));
   }
-  CopyConstruct(op, cur, dst);
+  CopyConstruct(op_, cur_, dst);
 }
 
 void CommandLineFlag::Write(const void* src,
@@ -330,28 +330,28 @@ void CommandLineFlag::Write(const void* src,
   // `src_op` is the marshalling operation corresponding to the declaration
   // visible at the call site. `op` is the Flag's defined marshalling operation.
   // They must match for this operation to be well-defined.
-  if (ABSL_PREDICT_FALSE(src_op != op)) {
+  if (ABSL_PREDICT_FALSE(src_op != op_)) {
     ABSL_INTERNAL_LOG(
         ERROR,
-        absl::StrCat("Flag '", name,
+        absl::StrCat("Flag '", Name(),
                      "' is defined as one type and declared as another"));
   }
 
   if (ShouldValidateFlagValue(*this)) {
-    void* obj = Clone(op, src);
+    void* obj = Clone(op_, src);
     std::string ignored_error;
-    std::string src_as_str = Unparse(marshalling_op, src);
-    if (!Parse(marshalling_op, src_as_str, obj, &ignored_error) ||
+    std::string src_as_str = Unparse(marshalling_op_, src);
+    if (!Parse(marshalling_op_, src_as_str, obj, &ignored_error) ||
         !InvokeValidator(obj)) {
-      ABSL_INTERNAL_LOG(ERROR, absl::StrCat("Attempt to set flag '", name,
+      ABSL_INTERNAL_LOG(ERROR, absl::StrCat("Attempt to set flag '", Name(),
                                             "' to invalid value ", src_as_str));
     }
-    Delete(op, obj);
+    Delete(op_, obj);
   }
 
-  modified = true;
-  counter++;
-  Copy(op, src, cur);
+  modified_ = true;
+  counter_++;
+  Copy(op_, src, cur_);
 
   UpdateCopy(this);
   InvokeCallback();
diff --git a/absl/flags/internal/commandlineflag.h b/absl/flags/internal/commandlineflag.h
index 23512576..572568b9 100644
--- a/absl/flags/internal/commandlineflag.h
+++ b/absl/flags/internal/commandlineflag.h
@@ -69,8 +69,6 @@ using HelpGenFunc = std::string (*)();
 // based on default value supplied in flag's definition)
 using InitialValGenFunc = void* (*)();
 
-struct CommandLineFlagInfo;
-
 extern const char kStrippedFlagHelp[];
 
 // The per-type function
@@ -189,27 +187,28 @@ class HelpText {
 };
 
 // Holds all information for a flag.
-struct CommandLineFlag {
+class CommandLineFlag {
+ public:
   constexpr CommandLineFlag(
-      const char* name_arg, HelpText help_text, const char* filename_arg,
-      const flags_internal::FlagOpFn op_arg,
-      const flags_internal::FlagMarshallingOpFn marshalling_op_arg,
-      const flags_internal::InitialValGenFunc initial_value_gen, void* def_arg,
-      void* cur_arg)
-      : name(name_arg),
-        help(help_text),
-        filename(filename_arg),
-        op(op_arg),
-        marshalling_op(marshalling_op_arg),
-        make_init_value(initial_value_gen),
-        inited(false),
-        modified(false),
-        on_command_line(false),
-        def(def_arg),
-        cur(cur_arg),
-        counter(0),
-        atomic(kAtomicInit),
-        locks(nullptr) {}
+      const char* name, HelpText help_text, const char* filename,
+      const flags_internal::FlagOpFn op,
+      const flags_internal::FlagMarshallingOpFn marshalling_op,
+      const flags_internal::InitialValGenFunc initial_value_gen, void* def,
+      void* cur)
+      : name_(name),
+        help_(help_text),
+        filename_(filename),
+        op_(op),
+        marshalling_op_(marshalling_op),
+        make_init_value_(initial_value_gen),
+        inited_(false),
+        modified_(false),
+        on_command_line_(false),
+        def_(def),
+        cur_(cur),
+        counter_(0),
+        atomic_(kAtomicInit),
+        locks_(nullptr) {}
 
   // Virtual destructor
   virtual void Destroy() const = 0;
@@ -225,8 +224,8 @@ struct CommandLineFlag {
   // Returns true iff this is a handle to an Abseil Flag.
   virtual bool IsAbseilFlag() const { return true; }
 
-  absl::string_view Name() const { return name; }
-  std::string Help() const { return help.GetHelpText(); }
+  absl::string_view Name() const { return name_; }
+  std::string Help() const { return help_.GetHelpText(); }
   bool IsModified() const;
   void SetModified(bool is_modified);
   bool IsSpecifiedOnCommandLine() const;
@@ -247,15 +246,14 @@ struct CommandLineFlag {
   // Return true iff flag has type T.
   template <typename T>
   inline bool IsOfType() const {
-    return this->op == &flags_internal::FlagOps<T>;
+    return op_ == &flags_internal::FlagOps<T>;
   }
 
   // Attempts to retrieve the flag value. Returns value on success,
   // absl::nullopt otherwise.
   template <typename T>
   absl::optional<T> Get() const {
-    if (IsRetired() || flags_internal::FlagOps<T> != this->op)
-      return absl::nullopt;
+    if (IsRetired() || flags_internal::FlagOps<T> != op_) return absl::nullopt;
 
     T res;
     Read(&res, flags_internal::FlagOps<T>);
@@ -286,36 +284,36 @@ struct CommandLineFlag {
  protected:
   ~CommandLineFlag() = default;
 
-  const char* const name;
-  const HelpText help;
-  const char* const filename;
+  const char* const name_;
+  const HelpText help_;
+  const char* const filename_;
 
-  const FlagOpFn op;                         // Type-specific handler
-  const FlagMarshallingOpFn marshalling_op;  // Marshalling ops handler
-  const InitialValGenFunc make_init_value;   // Makes initial value for the flag
-  std::atomic<bool> inited;  // fields have been lazily initialized
+  const FlagOpFn op_;                         // Type-specific handler
+  const FlagMarshallingOpFn marshalling_op_;  // Marshalling ops handler
+  const InitialValGenFunc make_init_value_;  // Makes initial value for the flag
+  std::atomic<bool> inited_;  // fields have been lazily initialized
 
-  // Mutable state (guarded by locks->primary_mu).
-  bool modified;            // Has flag value been modified?
-  bool on_command_line;     // Specified on command line.
-  void* def;                // Lazily initialized pointer to default value
-  void* cur;                // Lazily initialized pointer to current value
-  int64_t counter;            // Mutation counter
+  // Mutable state (guarded by locks_->primary_mu).
+  bool modified_;         // Has flag value been modified?
+  bool on_command_line_;  // Specified on command line.
+  void* def_;             // Lazily initialized pointer to default value
+  void* cur_;             // Lazily initialized pointer to current value
+  int64_t counter_;         // Mutation counter
 
   // For some types, a copy of the current value is kept in an atomically
   // accessible field.
   static const int64_t kAtomicInit = 0xababababababababll;
-  std::atomic<int64_t> atomic;
+  std::atomic<int64_t> atomic_;
 
   // Lazily initialized mutexes for this flag value.  We cannot inline a
   // SpinLock or Mutex here because those have non-constexpr constructors and
   // so would prevent constant initialization of this type.
   // TODO(rogeeff): fix it once Mutex has constexpr constructor
-  struct CommandLineFlagLocks* locks;  // locks, laziliy allocated.
+  struct CommandLineFlagLocks* locks_;  // locks, laziliy allocated.
 
   // Ensure that the lazily initialized fields of *flag have been initialized,
   // and return the lock which should be locked when flag's state is mutated.
-  absl::Mutex* InitFlagIfNecessary() const LOCK_RETURNED(locks->primary_mu);
+  absl::Mutex* InitFlagIfNecessary() const ABSL_LOCK_RETURNED(locks_->primary_mu);
 
   // copy construct new value of flag's type in a memory referenced by dst
   // based on current flag's value
@@ -326,8 +324,6 @@ struct CommandLineFlag {
   friend class FlagRegistry;
   friend class FlagPtrMap;
   friend class FlagSaverImpl;
-  friend void FillCommandLineFlagInfo(CommandLineFlag* flag,
-                                      CommandLineFlagInfo* result);
   friend bool TryParseLocked(CommandLineFlag* flag, void* dst,
                              absl::string_view value, std::string* err);
   friend absl::Mutex* InitFlag(CommandLineFlag* flag);
@@ -335,7 +331,7 @@ struct CommandLineFlag {
   // This is a short term, until we completely rework persistent state
   // storage API.
   virtual void* GetValidator() const { return nullptr; }
-  virtual void SetValidator(void*) {}
+  virtual bool SetValidator(void*) { return false; }
 };
 
 // Update any copy of the flag value that is stored in an atomic word.
diff --git a/absl/flags/internal/flag.cc b/absl/flags/internal/flag.cc
index 34629b30..0f403581 100644
--- a/absl/flags/internal/flag.cc
+++ b/absl/flags/internal/flag.cc
@@ -32,7 +32,7 @@ namespace flags_internal {
 // completed. Requires that *primary_lock be held in exclusive mode; it may be
 // released and reacquired by the implementation.
 void InvokeCallback(absl::Mutex* primary_mu, absl::Mutex* callback_mu,
-                    FlagCallback cb) EXCLUSIVE_LOCKS_REQUIRED(primary_mu) {
+                    FlagCallback cb) ABSL_EXCLUSIVE_LOCKS_REQUIRED(primary_mu) {
   if (!cb) return;
 
   // When executing the callback we need the primary flag's mutex to be
diff --git a/absl/flags/internal/flag.h b/absl/flags/internal/flag.h
index fad36877..a84f7fa8 100644
--- a/absl/flags/internal/flag.h
+++ b/absl/flags/internal/flag.h
@@ -28,23 +28,22 @@ namespace flags_internal {
 using FlagCallback = void (*)();
 
 void InvokeCallback(absl::Mutex* primary_mu, absl::Mutex* callback_mu,
-                    FlagCallback cb) EXCLUSIVE_LOCKS_REQUIRED(primary_mu);
+                    FlagCallback cb) ABSL_EXCLUSIVE_LOCKS_REQUIRED(primary_mu);
 
 // This is "unspecified" implementation of absl::Flag<T> type.
 template <typename T>
 class Flag final : public flags_internal::CommandLineFlag {
  public:
-  constexpr Flag(const char* name_arg,
-                 const flags_internal::HelpGenFunc help_gen,
-                 const char* filename_arg,
-                 const flags_internal::FlagMarshallingOpFn marshalling_op_arg,
+  constexpr Flag(const char* name, const flags_internal::HelpGenFunc help_gen,
+                 const char* filename,
+                 const flags_internal::FlagMarshallingOpFn marshalling_op,
                  const flags_internal::InitialValGenFunc initial_value_gen)
       : flags_internal::CommandLineFlag(
-            name_arg, flags_internal::HelpText::FromFunctionPointer(help_gen),
-            filename_arg, &flags_internal::FlagOps<T>, marshalling_op_arg,
+            name, flags_internal::HelpText::FromFunctionPointer(help_gen),
+            filename, &flags_internal::FlagOps<T>, marshalling_op,
             initial_value_gen,
-            /*def_arg=*/nullptr,
-            /*cur_arg=*/nullptr),
+            /*def=*/nullptr,
+            /*cur=*/nullptr),
         callback_(nullptr) {}
 
   T Get() const {
@@ -71,12 +70,12 @@ class Flag final : public flags_internal::CommandLineFlag {
     };
     U u;
 
-    this->Read(&u.value, &flags_internal::FlagOps<T>);
+    Read(&u.value, &flags_internal::FlagOps<T>);
     return std::move(u.value);
   }
 
   bool AtomicGet(T* v) const {
-    const int64_t r = this->atomic.load(std::memory_order_acquire);
+    const int64_t r = atomic_.load(std::memory_order_acquire);
     if (r != flags_internal::CommandLineFlag::kAtomicInit) {
       memcpy(v, &r, sizeof(T));
       return true;
@@ -85,7 +84,7 @@ class Flag final : public flags_internal::CommandLineFlag {
     return false;
   }
 
-  void Set(const T& v) { this->Write(&v, &flags_internal::FlagOps<T>); }
+  void Set(const T& v) { Write(&v, &flags_internal::FlagOps<T>); }
 
   void SetCallback(const flags_internal::FlagCallback mutation_callback) {
     absl::MutexLock l(InitFlagIfNecessary());
@@ -95,18 +94,18 @@ class Flag final : public flags_internal::CommandLineFlag {
     InvokeCallback();
   }
   void InvokeCallback() override
-      EXCLUSIVE_LOCKS_REQUIRED(this->locks->primary_mu) {
-    flags_internal::InvokeCallback(&this->locks->primary_mu,
-                                   &this->locks->callback_mu, callback_);
+      ABSL_EXCLUSIVE_LOCKS_REQUIRED(locks_->primary_mu) {
+    flags_internal::InvokeCallback(&locks_->primary_mu, &locks_->callback_mu,
+                                   callback_);
   }
 
  private:
   void Destroy() const override {
     // Values are heap allocated Abseil Flags.
-    if (this->cur) Delete(this->op, this->cur);
-    if (this->def) Delete(this->op, this->def);
+    if (cur_) Delete(op_, cur_);
+    if (def_) Delete(op_, def_);
 
-    delete this->locks;
+    delete locks_;
   }
 
   // Flag's data
diff --git a/absl/flags/internal/program_name.cc b/absl/flags/internal/program_name.cc
index 62be645a..f0811f14 100644
--- a/absl/flags/internal/program_name.cc
+++ b/absl/flags/internal/program_name.cc
@@ -25,7 +25,7 @@ namespace flags_internal {
 
 ABSL_CONST_INIT static absl::Mutex program_name_guard(absl::kConstInit);
 ABSL_CONST_INIT static std::string* program_name
-    GUARDED_BY(program_name_guard) = nullptr;
+    ABSL_GUARDED_BY(program_name_guard) = nullptr;
 
 std::string ProgramInvocationName() {
   absl::MutexLock l(&program_name_guard);
diff --git a/absl/flags/internal/registry.cc b/absl/flags/internal/registry.cc
index 0d4eec98..4bea313b 100644
--- a/absl/flags/internal/registry.cc
+++ b/absl/flags/internal/registry.cc
@@ -54,8 +54,8 @@ class FlagRegistry {
   // Store a flag in this registry.  Takes ownership of *flag.
   void RegisterFlag(CommandLineFlag* flag);
 
-  void Lock() EXCLUSIVE_LOCK_FUNCTION(lock_) { lock_.Lock(); }
-  void Unlock() UNLOCK_FUNCTION(lock_) { lock_.Unlock(); }
+  void Lock() ABSL_EXCLUSIVE_LOCK_FUNCTION(lock_) { lock_.Lock(); }
+  void Unlock() ABSL_UNLOCK_FUNCTION(lock_) { lock_.Unlock(); }
 
   // Returns the flag object for the specified name, or nullptr if not found.
   // Will emit a warning if a 'retired' flag is specified.
@@ -118,7 +118,7 @@ void FlagRegistry::RegisterFlag(CommandLineFlag* flag) {
               (flag->IsRetired() ? old_flag->Filename() : flag->Filename()),
               "'."),
           true);
-    } else if (flag->op != old_flag->op) {
+    } else if (flag->op_ != old_flag->op_) {
       flags_internal::ReportUsageError(
           absl::StrCat("Flag '", flag->Name(),
                        "' was defined more than once but with "
@@ -208,16 +208,16 @@ class FlagSaverImpl {
       if (flag->IsRetired()) return;
 
       saved.name = flag->Name();
-      saved.op = flag->op;
-      saved.marshalling_op = flag->marshalling_op;
+      saved.op = flag->op_;
+      saved.marshalling_op = flag->marshalling_op_;
       {
         absl::MutexLock l(flag->InitFlagIfNecessary());
         saved.validator = flag->GetValidator();
-        saved.modified = flag->modified;
-        saved.on_command_line = flag->on_command_line;
-        saved.current = Clone(saved.op, flag->cur);
-        saved.default_value = Clone(saved.op, flag->def);
-        saved.counter = flag->counter;
+        saved.modified = flag->modified_;
+        saved.on_command_line = flag->on_command_line_;
+        saved.current = Clone(saved.op, flag->cur_);
+        saved.default_value = Clone(saved.op, flag->def_);
+        saved.counter = flag->counter_;
       }
       backup_registry_.push_back(saved);
     });
@@ -237,26 +237,28 @@ class FlagSaverImpl {
 
       bool restored = false;
       {
-        absl::MutexLock l(flag->InitFlagIfNecessary());
+        // This function encapsulate the lock.
         flag->SetValidator(src.validator);
-        flag->modified = src.modified;
-        flag->on_command_line = src.on_command_line;
-        if (flag->counter != src.counter ||
-            ChangedDirectly(flag, src.default_value, flag->def)) {
+
+        absl::MutexLock l(flag->InitFlagIfNecessary());
+        flag->modified_ = src.modified;
+        flag->on_command_line_ = src.on_command_line;
+        if (flag->counter_ != src.counter ||
+            ChangedDirectly(flag, src.default_value, flag->def_)) {
           restored = true;
-          Copy(src.op, src.default_value, flag->def);
+          Copy(src.op, src.default_value, flag->def_);
         }
-        if (flag->counter != src.counter ||
-            ChangedDirectly(flag, src.current, flag->cur)) {
+        if (flag->counter_ != src.counter ||
+            ChangedDirectly(flag, src.current, flag->cur_)) {
           restored = true;
-          Copy(src.op, src.current, flag->cur);
+          Copy(src.op, src.current, flag->cur_);
           UpdateCopy(flag);
           flag->InvokeCallback();
         }
       }
 
       if (restored) {
-        flag->counter++;
+        flag->counter_++;
 
         // Revalidate the flag because the validator might store state based
         // on the flag's value, which just changed due to the restore.
@@ -308,44 +310,6 @@ FlagSaver::~FlagSaver() {
 }
 
 // --------------------------------------------------------------------
-// GetAllFlags()
-//    The main way the FlagRegistry class exposes its data.  This
-//    returns, as strings, all the info about all the flags in
-//    the main registry, sorted first by filename they are defined
-//    in, and then by flagname.
-// --------------------------------------------------------------------
-
-struct FilenameFlagnameLess {
-  bool operator()(const CommandLineFlagInfo& a,
-                  const CommandLineFlagInfo& b) const {
-    int cmp = absl::string_view(a.filename).compare(b.filename);
-    if (cmp != 0) return cmp < 0;
-    return a.name < b.name;
-  }
-};
-
-void FillCommandLineFlagInfo(CommandLineFlag* flag,
-                             CommandLineFlagInfo* result) {
-  result->name = std::string(flag->Name());
-  result->type = std::string(flag->Typename());
-  result->description = flag->Help();
-  result->filename = flag->Filename();
-
-  if (!flag->IsAbseilFlag()) {
-    if (!flag->IsModified() && ChangedDirectly(flag, flag->cur, flag->def)) {
-      flag->modified = true;
-    }
-  }
-
-  result->current_value = flag->CurrentValue();
-  result->default_value = flag->DefaultValue();
-  result->is_default = !flag->IsModified();
-  result->has_validator_fn = flag->HasValidatorFn();
-  absl::MutexLock l(flag->InitFlagIfNecessary());
-  result->flag_ptr = flag->IsAbseilFlag() ? nullptr : flag->cur;
-}
-
-// --------------------------------------------------------------------
 
 CommandLineFlag* FindCommandLineFlag(absl::string_view name) {
   if (name.empty()) return nullptr;
@@ -380,21 +344,6 @@ void ForEachFlag(std::function<void(CommandLineFlag*)> visitor) {
 
 // --------------------------------------------------------------------
 
-void GetAllFlags(std::vector<CommandLineFlagInfo>* OUTPUT) {
-  flags_internal::ForEachFlag([&](CommandLineFlag* flag) {
-    if (flag->IsRetired()) return;
-
-    CommandLineFlagInfo fi;
-    FillCommandLineFlagInfo(flag, &fi);
-    OUTPUT->push_back(fi);
-  });
-
-  // Now sort the flags, first by filename they occur in, then alphabetically
-  std::sort(OUTPUT->begin(), OUTPUT->end(), FilenameFlagnameLess());
-}
-
-// --------------------------------------------------------------------
-
 bool RegisterCommandLineFlag(CommandLineFlag* flag) {
   FlagRegistry::GlobalRegistry()->RegisterFlag(flag);
   return true;
@@ -406,24 +355,24 @@ namespace {
 
 class RetiredFlagObj final : public flags_internal::CommandLineFlag {
  public:
-  constexpr RetiredFlagObj(const char* name_arg, FlagOpFn ops,
+  constexpr RetiredFlagObj(const char* name, FlagOpFn ops,
                            FlagMarshallingOpFn marshalling_ops)
       : flags_internal::CommandLineFlag(
-            name_arg, flags_internal::HelpText::FromStaticCString(nullptr),
-            /*filename_arg=*/"RETIRED", ops, marshalling_ops,
+            name, flags_internal::HelpText::FromStaticCString(nullptr),
+            /*filename=*/"RETIRED", ops, marshalling_ops,
             /*initial_value_gen=*/nullptr,
-            /*def_arg=*/nullptr,
-            /*cur_arg=*/nullptr) {}
+            /*def=*/nullptr,
+            /*cur=*/nullptr) {}
 
  private:
   bool IsRetired() const override { return true; }
 
   void Destroy() const override {
     // Values are heap allocated for Retired Flags.
-    if (this->cur) Delete(this->op, this->cur);
-    if (this->def) Delete(this->op, this->def);
+    if (cur_) Delete(op_, cur_);
+    if (def_) Delete(op_, def_);
 
-    if (this->locks) delete this->locks;
+    if (locks_) delete locks_;
 
     delete this;
   }
diff --git a/absl/flags/internal/registry.h b/absl/flags/internal/registry.h
index 884a8db5..eb134a9f 100644
--- a/absl/flags/internal/registry.h
+++ b/absl/flags/internal/registry.h
@@ -29,33 +29,6 @@
 namespace absl {
 namespace flags_internal {
 
-// CommandLineFlagInfo holds all information for a flag.
-struct CommandLineFlagInfo {
-  std::string name;           // the name of the flag
-  std::string type;           // DO NOT use. Use flag->IsOfType<T>() instead.
-  std::string description;    // the "help text" associated with the flag
-  std::string current_value;  // the current value, as a std::string
-  std::string default_value;  // the default value, as a std::string
-  std::string filename;       // 'cleaned' version of filename holding the flag
-  bool has_validator_fn;  // true if RegisterFlagValidator called on this flag
-
-  bool is_default;  // true if the flag has the default value and
-                    // has not been set explicitly from the cmdline
-                    // or via SetCommandLineOption.
-
-  // nullptr for ABSL_FLAG.  A pointer to the flag's current value
-  // otherwise.  E.g., for DEFINE_int32(foo, ...), flag_ptr will be
-  // &FLAGS_foo.
-  const void* flag_ptr;
-};
-
-//-----------------------------------------------------------------------------
-
-void FillCommandLineFlagInfo(CommandLineFlag* flag,
-                             CommandLineFlagInfo* result);
-
-//-----------------------------------------------------------------------------
-
 CommandLineFlag* FindCommandLineFlag(absl::string_view name);
 CommandLineFlag* FindRetiredFlag(absl::string_view name);
 
@@ -68,11 +41,6 @@ void ForEachFlag(std::function<void(CommandLineFlag*)> visitor);
 
 //-----------------------------------------------------------------------------
 
-// Store the list of all flags in *OUTPUT, sorted by file.
-void GetAllFlags(std::vector<CommandLineFlagInfo>* OUTPUT);
-
-//-----------------------------------------------------------------------------
-
 bool RegisterCommandLineFlag(CommandLineFlag*);
 
 //-----------------------------------------------------------------------------
diff --git a/absl/flags/internal/type_erased.cc b/absl/flags/internal/type_erased.cc
index 2984291c..a1650fcf 100644
--- a/absl/flags/internal/type_erased.cc
+++ b/absl/flags/internal/type_erased.cc
@@ -36,30 +36,6 @@ bool GetCommandLineOption(absl::string_view name, std::string* value) {
   return true;
 }
 
-bool GetCommandLineFlagInfo(absl::string_view name,
-                            CommandLineFlagInfo* OUTPUT) {
-  if (name.empty()) return false;
-
-  CommandLineFlag* flag = flags_internal::FindCommandLineFlag(name);
-  if (flag == nullptr || flag->IsRetired()) {
-    return false;
-  }
-
-  assert(OUTPUT);
-  FillCommandLineFlagInfo(flag, OUTPUT);
-  return true;
-}
-
-CommandLineFlagInfo GetCommandLineFlagInfoOrDie(absl::string_view name) {
-  CommandLineFlagInfo info;
-  if (!GetCommandLineFlagInfo(name, &info)) {
-    ABSL_INTERNAL_LOG(FATAL, absl::StrCat("Flag '", name, "' does not exist"));
-  }
-  return info;
-}
-
-// --------------------------------------------------------------------
-
 bool SetCommandLineOption(absl::string_view name, absl::string_view value) {
   return SetCommandLineOptionWithMode(name, value,
                                       flags_internal::SET_FLAGS_VALUE);
diff --git a/absl/flags/internal/type_erased.h b/absl/flags/internal/type_erased.h
index 249d36b9..a9551166 100644
--- a/absl/flags/internal/type_erased.h
+++ b/absl/flags/internal/type_erased.h
@@ -32,17 +32,6 @@ namespace flags_internal {
 // Thread-safe.
 bool GetCommandLineOption(absl::string_view name, std::string* value);
 
-// If a flag named "name" exists, store its information in *OUTPUT
-// and return true.  Else return false without changing *OUTPUT.
-// Thread-safe.
-bool GetCommandLineFlagInfo(absl::string_view name,
-                            CommandLineFlagInfo* OUTPUT);
-
-// Returns the CommandLineFlagInfo of the flagname.  exit() with an
-// error code if name not found.
-// Thread-safe.
-CommandLineFlagInfo GetCommandLineFlagInfoOrDie(absl::string_view name);
-
 // Set the value of the flag named "name" to value.  If successful,
 // returns true.  If not successful (e.g., the flag was not found or
 // the value is not a valid value), returns false.
diff --git a/absl/flags/parse.cc b/absl/flags/parse.cc
index e9dd4204..16c4d68f 100644
--- a/absl/flags/parse.cc
+++ b/absl/flags/parse.cc
@@ -44,11 +44,11 @@ namespace {
 ABSL_CONST_INIT absl::Mutex processing_checks_guard(absl::kConstInit);
 
 ABSL_CONST_INIT bool flagfile_needs_processing
-    GUARDED_BY(processing_checks_guard) = false;
+    ABSL_GUARDED_BY(processing_checks_guard) = false;
 ABSL_CONST_INIT bool fromenv_needs_processing
-    GUARDED_BY(processing_checks_guard) = false;
+    ABSL_GUARDED_BY(processing_checks_guard) = false;
 ABSL_CONST_INIT bool tryfromenv_needs_processing
-    GUARDED_BY(processing_checks_guard) = false;
+    ABSL_GUARDED_BY(processing_checks_guard) = false;
 
 }  // namespace
 }  // namespace flags_internal
diff --git a/absl/flags/usage.cc b/absl/flags/usage.cc
index 4c01f510..dff7a3da 100644
--- a/absl/flags/usage.cc
+++ b/absl/flags/usage.cc
@@ -24,7 +24,7 @@ namespace flags_internal {
 namespace {
 ABSL_CONST_INIT absl::Mutex usage_message_guard(absl::kConstInit);
 ABSL_CONST_INIT std::string* program_usage_message
-    GUARDED_BY(usage_message_guard) = nullptr;
+    ABSL_GUARDED_BY(usage_message_guard) = nullptr;
 }  // namespace
 }  // namespace flags_internal
 
diff --git a/absl/flags/usage_config.cc b/absl/flags/usage_config.cc
index d34ecfc8..f97bf300 100644
--- a/absl/flags/usage_config.cc
+++ b/absl/flags/usage_config.cc
@@ -94,7 +94,7 @@ std::string NormalizeFilename(absl::string_view filename) {
 
 ABSL_CONST_INIT absl::Mutex custom_usage_config_guard(absl::kConstInit);
 ABSL_CONST_INIT FlagsUsageConfig* custom_usage_config
-    GUARDED_BY(custom_usage_config_guard) = nullptr;
+    ABSL_GUARDED_BY(custom_usage_config_guard) = nullptr;
 
 }  // namespace