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-rw-r--r--third_party/abseil_cpp/absl/flags/parse.cc812
1 files changed, 0 insertions, 812 deletions
diff --git a/third_party/abseil_cpp/absl/flags/parse.cc b/third_party/abseil_cpp/absl/flags/parse.cc
deleted file mode 100644
index e2c88ff863..0000000000
--- a/third_party/abseil_cpp/absl/flags/parse.cc
+++ /dev/null
@@ -1,812 +0,0 @@
-//
-// Copyright 2019 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include "absl/flags/parse.h"
-
-#include <stdlib.h>
-
-#include <algorithm>
-#include <fstream>
-#include <iostream>
-#include <iterator>
-#include <string>
-#include <tuple>
-#include <utility>
-#include <vector>
-
-#ifdef _WIN32
-#include <windows.h>
-#endif
-
-#include "absl/base/attributes.h"
-#include "absl/base/config.h"
-#include "absl/base/const_init.h"
-#include "absl/base/thread_annotations.h"
-#include "absl/flags/commandlineflag.h"
-#include "absl/flags/config.h"
-#include "absl/flags/flag.h"
-#include "absl/flags/internal/commandlineflag.h"
-#include "absl/flags/internal/flag.h"
-#include "absl/flags/internal/parse.h"
-#include "absl/flags/internal/private_handle_accessor.h"
-#include "absl/flags/internal/program_name.h"
-#include "absl/flags/internal/usage.h"
-#include "absl/flags/reflection.h"
-#include "absl/flags/usage.h"
-#include "absl/flags/usage_config.h"
-#include "absl/strings/ascii.h"
-#include "absl/strings/str_cat.h"
-#include "absl/strings/string_view.h"
-#include "absl/strings/strip.h"
-#include "absl/synchronization/mutex.h"
-
-// --------------------------------------------------------------------
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace flags_internal {
-namespace {
-
-ABSL_CONST_INIT absl::Mutex processing_checks_guard(absl::kConstInit);
-
-ABSL_CONST_INIT bool flagfile_needs_processing
-    ABSL_GUARDED_BY(processing_checks_guard) = false;
-ABSL_CONST_INIT bool fromenv_needs_processing
-    ABSL_GUARDED_BY(processing_checks_guard) = false;
-ABSL_CONST_INIT bool tryfromenv_needs_processing
-    ABSL_GUARDED_BY(processing_checks_guard) = false;
-
-ABSL_CONST_INIT absl::Mutex specified_flags_guard(absl::kConstInit);
-ABSL_CONST_INIT std::vector<const CommandLineFlag*>* specified_flags
-    ABSL_GUARDED_BY(specified_flags_guard) = nullptr;
-
-struct SpecifiedFlagsCompare {
-  bool operator()(const CommandLineFlag* a, const CommandLineFlag* b) const {
-    return a->Name() < b->Name();
-  }
-  bool operator()(const CommandLineFlag* a, absl::string_view b) const {
-    return a->Name() < b;
-  }
-  bool operator()(absl::string_view a, const CommandLineFlag* b) const {
-    return a < b->Name();
-  }
-};
-
-}  // namespace
-}  // namespace flags_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-ABSL_FLAG(std::vector<std::string>, flagfile, {},
-          "comma-separated list of files to load flags from")
-    .OnUpdate([]() {
-      if (absl::GetFlag(FLAGS_flagfile).empty()) return;
-
-      absl::MutexLock l(&absl::flags_internal::processing_checks_guard);
-
-      // Setting this flag twice before it is handled most likely an internal
-      // error and should be reviewed by developers.
-      if (absl::flags_internal::flagfile_needs_processing) {
-        ABSL_INTERNAL_LOG(WARNING, "flagfile set twice before it is handled");
-      }
-
-      absl::flags_internal::flagfile_needs_processing = true;
-    });
-ABSL_FLAG(std::vector<std::string>, fromenv, {},
-          "comma-separated list of flags to set from the environment"
-          " [use 'export FLAGS_flag1=value']")
-    .OnUpdate([]() {
-      if (absl::GetFlag(FLAGS_fromenv).empty()) return;
-
-      absl::MutexLock l(&absl::flags_internal::processing_checks_guard);
-
-      // Setting this flag twice before it is handled most likely an internal
-      // error and should be reviewed by developers.
-      if (absl::flags_internal::fromenv_needs_processing) {
-        ABSL_INTERNAL_LOG(WARNING, "fromenv set twice before it is handled.");
-      }
-
-      absl::flags_internal::fromenv_needs_processing = true;
-    });
-ABSL_FLAG(std::vector<std::string>, tryfromenv, {},
-          "comma-separated list of flags to try to set from the environment if "
-          "present")
-    .OnUpdate([]() {
-      if (absl::GetFlag(FLAGS_tryfromenv).empty()) return;
-
-      absl::MutexLock l(&absl::flags_internal::processing_checks_guard);
-
-      // Setting this flag twice before it is handled most likely an internal
-      // error and should be reviewed by developers.
-      if (absl::flags_internal::tryfromenv_needs_processing) {
-        ABSL_INTERNAL_LOG(WARNING,
-                          "tryfromenv set twice before it is handled.");
-      }
-
-      absl::flags_internal::tryfromenv_needs_processing = true;
-    });
-
-ABSL_FLAG(std::vector<std::string>, undefok, {},
-          "comma-separated list of flag names that it is okay to specify "
-          "on the command line even if the program does not define a flag "
-          "with that name");
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace flags_internal {
-
-namespace {
-
-class ArgsList {
- public:
-  ArgsList() : next_arg_(0) {}
-  ArgsList(int argc, char* argv[]) : args_(argv, argv + argc), next_arg_(0) {}
-  explicit ArgsList(const std::vector<std::string>& args)
-      : args_(args), next_arg_(0) {}
-
-  // Returns success status: true if parsing successful, false otherwise.
-  bool ReadFromFlagfile(const std::string& flag_file_name);
-
-  int Size() const { return args_.size() - next_arg_; }
-  int FrontIndex() const { return next_arg_; }
-  absl::string_view Front() const { return args_[next_arg_]; }
-  void PopFront() { next_arg_++; }
-
- private:
-  std::vector<std::string> args_;
-  int next_arg_;
-};
-
-bool ArgsList::ReadFromFlagfile(const std::string& flag_file_name) {
-  std::ifstream flag_file(flag_file_name);
-
-  if (!flag_file) {
-    flags_internal::ReportUsageError(
-        absl::StrCat("Can't open flagfile ", flag_file_name), true);
-
-    return false;
-  }
-
-  // This argument represents fake argv[0], which should be present in all arg
-  // lists.
-  args_.push_back("");
-
-  std::string line;
-  bool success = true;
-
-  while (std::getline(flag_file, line)) {
-    absl::string_view stripped = absl::StripLeadingAsciiWhitespace(line);
-
-    if (stripped.empty() || stripped[0] == '#') {
-      // Comment or empty line; just ignore.
-      continue;
-    }
-
-    if (stripped[0] == '-') {
-      if (stripped == "--") {
-        flags_internal::ReportUsageError(
-            "Flagfile can't contain position arguments or --", true);
-
-        success = false;
-        break;
-      }
-
-      args_.push_back(std::string(stripped));
-      continue;
-    }
-
-    flags_internal::ReportUsageError(
-        absl::StrCat("Unexpected line in the flagfile ", flag_file_name, ": ",
-                     line),
-        true);
-
-    success = false;
-  }
-
-  return success;
-}
-
-// --------------------------------------------------------------------
-
-// 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) {
-#ifdef _WIN32
-  char buf[1024];
-  auto get_res = GetEnvironmentVariableA(var_name, buf, sizeof(buf));
-  if (get_res >= sizeof(buf)) {
-    return false;
-  }
-
-  if (get_res == 0) {
-    return false;
-  }
-
-  var_value = std::string(buf, get_res);
-#else
-  const char* val = ::getenv(var_name);
-  if (val == nullptr) {
-    return false;
-  }
-
-  var_value = val;
-#endif
-
-  return true;
-}
-
-// --------------------------------------------------------------------
-
-// Returns:
-//  Flag name or empty if arg= --
-//  Flag value after = in --flag=value (empty if --foo)
-//  "Is empty value" status. True if arg= --foo=, false otherwise. This is
-//  required to separate --foo from --foo=.
-// For example:
-//      arg           return values
-//   "--foo=bar" -> {"foo", "bar", false}.
-//   "--foo"     -> {"foo", "", false}.
-//   "--foo="    -> {"foo", "", true}.
-std::tuple<absl::string_view, absl::string_view, bool> SplitNameAndValue(
-    absl::string_view arg) {
-  // Allow -foo and --foo
-  absl::ConsumePrefix(&arg, "-");
-
-  if (arg.empty()) {
-    return std::make_tuple("", "", false);
-  }
-
-  auto equal_sign_pos = arg.find("=");
-
-  absl::string_view flag_name = arg.substr(0, equal_sign_pos);
-
-  absl::string_view value;
-  bool is_empty_value = false;
-
-  if (equal_sign_pos != absl::string_view::npos) {
-    value = arg.substr(equal_sign_pos + 1);
-    is_empty_value = value.empty();
-  }
-
-  return std::make_tuple(flag_name, value, is_empty_value);
-}
-
-// --------------------------------------------------------------------
-
-// Returns:
-//  found flag or nullptr
-//  is negative in case of --nofoo
-std::tuple<CommandLineFlag*, bool> LocateFlag(absl::string_view flag_name) {
-  CommandLineFlag* flag = absl::FindCommandLineFlag(flag_name);
-  bool is_negative = false;
-
-  if (!flag && absl::ConsumePrefix(&flag_name, "no")) {
-    flag = absl::FindCommandLineFlag(flag_name);
-    is_negative = true;
-  }
-
-  return std::make_tuple(flag, is_negative);
-}
-
-// --------------------------------------------------------------------
-
-// Verify that default values of typed flags must be convertible to string and
-// back.
-void CheckDefaultValuesParsingRoundtrip() {
-#ifndef NDEBUG
-  flags_internal::ForEachFlag([&](CommandLineFlag& flag) {
-    if (flag.IsRetired()) return;
-
-#define ABSL_FLAGS_INTERNAL_IGNORE_TYPE(T, _) \
-  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);
-  });
-#endif
-}
-
-// --------------------------------------------------------------------
-
-// Returns success status, which is true if we successfully read all flag files,
-// in which case new ArgLists are appended to the input_args in a reverse order
-// of file names in the input flagfiles list. This order ensures that flags from
-// 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) {
-  bool success = true;
-  for (auto it = flagfiles.rbegin(); it != flagfiles.rend(); ++it) {
-    ArgsList al;
-
-    if (al.ReadFromFlagfile(*it)) {
-      input_args.push_back(al);
-    } else {
-      success = false;
-    }
-  }
-
-  return success;
-}
-
-// Returns success status, which is true if were able to locate all environment
-// variables correctly or if fail_on_absent_in_env is false. The environment
-// variable names are expected to be of the form `FLAGS_<flag_name>`, where
-// `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,
-                      bool fail_on_absent_in_env) {
-  bool success = true;
-  std::vector<std::string> args;
-
-  // This argument represents fake argv[0], which should be present in all arg
-  // lists.
-  args.push_back("");
-
-  for (const auto& flag_name : flag_names) {
-    // Avoid infinite recursion.
-    if (flag_name == "fromenv" || flag_name == "tryfromenv") {
-      flags_internal::ReportUsageError(
-          absl::StrCat("Infinite recursion on flag ", flag_name), true);
-
-      success = false;
-      continue;
-    }
-
-    const std::string envname = absl::StrCat("FLAGS_", flag_name);
-    std::string envval;
-    if (!GetEnvVar(envname.c_str(), envval)) {
-      if (fail_on_absent_in_env) {
-        flags_internal::ReportUsageError(
-            absl::StrCat(envname, " not found in environment"), true);
-
-        success = false;
-      }
-
-      continue;
-    }
-
-    args.push_back(absl::StrCat("--", flag_name, "=", envval));
-  }
-
-  if (success) {
-    input_args.emplace_back(args);
-  }
-
-  return success;
-}
-
-// --------------------------------------------------------------------
-
-// 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 success = true;
-
-  absl::MutexLock l(&flags_internal::processing_checks_guard);
-
-  // flagfile could have been set either on a command line or
-  // programmatically before invoking ParseCommandLine. Note that we do not
-  // actually process arguments specified in the flagfile, but instead
-  // create a secondary arguments list to be processed along with the rest
-  // of the comamnd line arguments. Since we always the process most recently
-  // created list of arguments first, this will result in flagfile argument
-  // being processed before any other argument in the command line. If
-  // FLAGS_flagfile contains more than one file name we create multiple new
-  // levels of arguments in a reverse order of file names. Thus we always
-  // process arguments from first file before arguments containing in a
-  // second file, etc. If flagfile contains another
-  // --flagfile inside of it, it will produce new level of arguments and
-  // processed before the rest of the flagfile. We are also collecting all
-  // flagfiles set on original command line. Unlike the rest of the flags,
-  // this flag can be set multiple times and is expected to be handled
-  // multiple times. We are collecting them all into a single list and set
-  // the value of FLAGS_flagfile to that value at the end of the parsing.
-  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());
-    }
-
-    success &= ReadFlagfiles(flagfiles, input_args);
-
-    flags_internal::flagfile_needs_processing = false;
-  }
-
-  // Similar to flagfile fromenv/tryfromemv can be set both
-  // programmatically and at runtime on a command line. Unlike flagfile these
-  // can't be recursive.
-  if (flags_internal::fromenv_needs_processing) {
-    auto flags_list = absl::GetFlag(FLAGS_fromenv);
-
-    success &= ReadFlagsFromEnv(flags_list, input_args, true);
-
-    flags_internal::fromenv_needs_processing = false;
-  }
-
-  if (flags_internal::tryfromenv_needs_processing) {
-    auto flags_list = absl::GetFlag(FLAGS_tryfromenv);
-
-    success &= ReadFlagsFromEnv(flags_list, input_args, false);
-
-    flags_internal::tryfromenv_needs_processing = false;
-  }
-
-  return success;
-}
-
-// --------------------------------------------------------------------
-
-void ResetGeneratorFlags(const std::vector<std::string>& flagfile_value) {
-  // Setting flagfile to the value which collates all the values set on a
-  // command line and programmatically. So if command line looked like
-  // --flagfile=f1 --flagfile=f2 the final value of the FLAGS_flagfile flag is
-  // going to be {"f1", "f2"}
-  if (!flagfile_value.empty()) {
-    absl::SetFlag(&FLAGS_flagfile, flagfile_value);
-    absl::MutexLock l(&flags_internal::processing_checks_guard);
-    flags_internal::flagfile_needs_processing = false;
-  }
-
-  // fromenv/tryfromenv are set to <undefined> value.
-  if (!absl::GetFlag(FLAGS_fromenv).empty()) {
-    absl::SetFlag(&FLAGS_fromenv, {});
-  }
-  if (!absl::GetFlag(FLAGS_tryfromenv).empty()) {
-    absl::SetFlag(&FLAGS_tryfromenv, {});
-  }
-
-  absl::MutexLock l(&flags_internal::processing_checks_guard);
-  flags_internal::fromenv_needs_processing = false;
-  flags_internal::tryfromenv_needs_processing = false;
-}
-
-// --------------------------------------------------------------------
-
-// Returns:
-//  success status
-//  deduced value
-// We are also mutating curr_list in case if we need to get a hold of next
-// argument in the input.
-std::tuple<bool, absl::string_view> DeduceFlagValue(const CommandLineFlag& flag,
-                                                    absl::string_view value,
-                                                    bool is_negative,
-                                                    bool is_empty_value,
-                                                    ArgsList* curr_list) {
-  // Value is either an argument suffix after `=` in "--foo=<value>"
-  // or separate argument in case of "--foo" "<value>".
-
-  // boolean flags have these forms:
-  //   --foo
-  //   --nofoo
-  //   --foo=true
-  //   --foo=false
-  //   --nofoo=<value> is not supported
-  //   --foo <value> is not supported
-
-  // non boolean flags have these forms:
-  // --foo=<value>
-  // --foo <value>
-  // --nofoo is not supported
-
-  if (flag.IsOfType<bool>()) {
-    if (value.empty()) {
-      if (is_empty_value) {
-        // "--bool_flag=" case
-        flags_internal::ReportUsageError(
-            absl::StrCat(
-                "Missing the value after assignment for the boolean flag '",
-                flag.Name(), "'"),
-            true);
-        return std::make_tuple(false, "");
-      }
-
-      // "--bool_flag" case
-      value = is_negative ? "0" : "1";
-    } else if (is_negative) {
-      // "--nobool_flag=Y" case
-      flags_internal::ReportUsageError(
-          absl::StrCat("Negative form with assignment is not valid for the "
-                       "boolean flag '",
-                       flag.Name(), "'"),
-          true);
-      return std::make_tuple(false, "");
-    }
-  } else if (is_negative) {
-    // "--noint_flag=1" case
-    flags_internal::ReportUsageError(
-        absl::StrCat("Negative form is not valid for the flag '", flag.Name(),
-                     "'"),
-        true);
-    return std::make_tuple(false, "");
-  } else if (value.empty() && (!is_empty_value)) {
-    if (curr_list->Size() == 1) {
-      // "--int_flag" case
-      flags_internal::ReportUsageError(
-          absl::StrCat("Missing the value for the flag '", flag.Name(), "'"),
-          true);
-      return std::make_tuple(false, "");
-    }
-
-    // "--int_flag" "10" case
-    curr_list->PopFront();
-    value = curr_list->Front();
-
-    // Heuristic to detect the case where someone treats a string arg
-    // like a bool or just forgets to pass a value:
-    // --my_string_var --foo=bar
-    // We look for a flag of string type, whose value begins with a
-    // dash and corresponds to known flag or standalone --.
-    if (!value.empty() && value[0] == '-' && flag.IsOfType<std::string>()) {
-      auto maybe_flag_name = std::get<0>(SplitNameAndValue(value.substr(1)));
-
-      if (maybe_flag_name.empty() ||
-          std::get<0>(LocateFlag(maybe_flag_name)) != nullptr) {
-        // "--string_flag" "--known_flag" case
-        ABSL_INTERNAL_LOG(
-            WARNING,
-            absl::StrCat("Did you really mean to set flag '", flag.Name(),
-                         "' to the value '", value, "'?"));
-      }
-    }
-  }
-
-  return std::make_tuple(true, value);
-}
-
-// --------------------------------------------------------------------
-
-bool CanIgnoreUndefinedFlag(absl::string_view flag_name) {
-  auto undefok = absl::GetFlag(FLAGS_undefok);
-  if (std::find(undefok.begin(), undefok.end(), flag_name) != undefok.end()) {
-    return true;
-  }
-
-  if (absl::ConsumePrefix(&flag_name, "no") &&
-      std::find(undefok.begin(), undefok.end(), flag_name) != undefok.end()) {
-    return true;
-  }
-
-  return false;
-}
-
-}  // namespace
-
-// --------------------------------------------------------------------
-
-bool WasPresentOnCommandLine(absl::string_view flag_name) {
-  absl::MutexLock l(&specified_flags_guard);
-  ABSL_INTERNAL_CHECK(specified_flags != nullptr,
-                      "ParseCommandLine is not invoked yet");
-
-  return std::binary_search(specified_flags->begin(), specified_flags->end(),
-                            flag_name, SpecifiedFlagsCompare{});
-}
-
-// --------------------------------------------------------------------
-
-std::vector<char*> ParseCommandLineImpl(int argc, char* argv[],
-                                        ArgvListAction arg_list_act,
-                                        UsageFlagsAction usage_flag_act,
-                                        OnUndefinedFlag on_undef_flag) {
-  ABSL_INTERNAL_CHECK(argc > 0, "Missing argv[0]");
-
-  // This routine does not return anything since we abort on failure.
-  CheckDefaultValuesParsingRoundtrip();
-
-  std::vector<std::string> flagfile_value;
-
-  std::vector<ArgsList> input_args;
-  input_args.push_back(ArgsList(argc, argv));
-
-  std::vector<char*> output_args;
-  std::vector<char*> positional_args;
-  output_args.reserve(argc);
-
-  // This is the list of undefined flags. The element of the list is the pair
-  // consisting of boolean indicating if flag came from command line (vs from
-  // some flag file we've read) and flag name.
-  // TODO(rogeeff): Eliminate the first element in the pair after cleanup.
-  std::vector<std::pair<bool, std::string>> undefined_flag_names;
-
-  // Set program invocation name if it is not set before.
-  if (ProgramInvocationName() == "UNKNOWN") {
-    flags_internal::SetProgramInvocationName(argv[0]);
-  }
-  output_args.push_back(argv[0]);
-
-  absl::MutexLock l(&specified_flags_guard);
-  if (specified_flags == nullptr) {
-    specified_flags = new std::vector<const CommandLineFlag*>;
-  } else {
-    specified_flags->clear();
-  }
-
-  // Iterate through the list of the input arguments. First level are arguments
-  // originated from argc/argv. Following levels are arguments originated from
-  // recursive parsing of flagfile(s).
-  bool success = true;
-  while (!input_args.empty()) {
-    // 10. First we process the built-in generator flags.
-    success &= HandleGeneratorFlags(input_args, flagfile_value);
-
-    // 30. Select top-most (most recent) arguments list. If it is empty drop it
-    // and re-try.
-    ArgsList& curr_list = input_args.back();
-
-    curr_list.PopFront();
-
-    if (curr_list.Size() == 0) {
-      input_args.pop_back();
-      continue;
-    }
-
-    // 40. Pick up the front remaining argument in the current list. If current
-    // stack of argument lists contains only one element - we are processing an
-    // argument from the original argv.
-    absl::string_view arg(curr_list.Front());
-    bool arg_from_argv = input_args.size() == 1;
-
-    // 50. If argument does not start with - or is just "-" - this is
-    // positional argument.
-    if (!absl::ConsumePrefix(&arg, "-") || arg.empty()) {
-      ABSL_INTERNAL_CHECK(arg_from_argv,
-                          "Flagfile cannot contain positional argument");
-
-      positional_args.push_back(argv[curr_list.FrontIndex()]);
-      continue;
-    }
-
-    if (arg_from_argv && (arg_list_act == ArgvListAction::kKeepParsedArgs)) {
-      output_args.push_back(argv[curr_list.FrontIndex()]);
-    }
-
-    // 60. Split the current argument on '=' to figure out the argument
-    // name and value. If flag name is empty it means we've got "--". value
-    // can be empty either if there were no '=' in argument string at all or
-    // an argument looked like "--foo=". In a latter case is_empty_value is
-    // true.
-    absl::string_view flag_name;
-    absl::string_view value;
-    bool is_empty_value = false;
-
-    std::tie(flag_name, value, is_empty_value) = SplitNameAndValue(arg);
-
-    // 70. "--" alone means what it does for GNU: stop flags parsing. We do
-    // not support positional arguments in flagfiles, so we just drop them.
-    if (flag_name.empty()) {
-      ABSL_INTERNAL_CHECK(arg_from_argv,
-                          "Flagfile cannot contain positional argument");
-
-      curr_list.PopFront();
-      break;
-    }
-
-    // 80. Locate the flag based on flag name. Handle both --foo and --nofoo
-    CommandLineFlag* flag = nullptr;
-    bool is_negative = false;
-    std::tie(flag, is_negative) = LocateFlag(flag_name);
-
-    if (flag == nullptr) {
-      if (on_undef_flag != OnUndefinedFlag::kIgnoreUndefined) {
-        undefined_flag_names.emplace_back(arg_from_argv,
-                                          std::string(flag_name));
-      }
-      continue;
-    }
-
-    // 90. Deduce flag's value (from this or next argument)
-    auto curr_index = curr_list.FrontIndex();
-    bool value_success = true;
-    std::tie(value_success, value) =
-        DeduceFlagValue(*flag, value, is_negative, is_empty_value, &curr_list);
-    success &= value_success;
-
-    // If above call consumed an argument, it was a standalone value
-    if (arg_from_argv && (arg_list_act == ArgvListAction::kKeepParsedArgs) &&
-        (curr_index != curr_list.FrontIndex())) {
-      output_args.push_back(argv[curr_list.FrontIndex()]);
-    }
-
-    // 100. Set the located flag to a new new value, unless it is retired.
-    // Setting retired flag fails, but we ignoring it here.
-    if (flag->IsRetired()) continue;
-
-    std::string error;
-    if (!flags_internal::PrivateHandleAccessor::ParseFrom(
-            *flag, value, SET_FLAGS_VALUE, kCommandLine, error)) {
-      flags_internal::ReportUsageError(error, true);
-      success = false;
-    } else {
-      specified_flags->push_back(flag);
-    }
-  }
-
-  for (const auto& flag_name : undefined_flag_names) {
-    if (CanIgnoreUndefinedFlag(flag_name.second)) continue;
-
-    flags_internal::ReportUsageError(
-        absl::StrCat("Unknown command line flag '", flag_name.second, "'"),
-        true);
-
-    success = false;
-  }
-
-#if ABSL_FLAGS_STRIP_NAMES
-  if (!success) {
-    flags_internal::ReportUsageError(
-        "NOTE: command line flags are disabled in this build", true);
-  }
-#endif
-
-  if (!success) {
-    flags_internal::HandleUsageFlags(std::cout,
-                                     ProgramUsageMessage());
-    std::exit(1);
-  }
-
-  if (usage_flag_act == UsageFlagsAction::kHandleUsage) {
-    int exit_code = flags_internal::HandleUsageFlags(
-        std::cout, ProgramUsageMessage());
-
-    if (exit_code != -1) {
-      std::exit(exit_code);
-    }
-  }
-
-  ResetGeneratorFlags(flagfile_value);
-
-  // Reinstate positional args which were intermixed with flags in the arguments
-  // list.
-  for (auto arg : positional_args) {
-    output_args.push_back(arg);
-  }
-
-  // All the remaining arguments are positional.
-  if (!input_args.empty()) {
-    for (int arg_index = input_args.back().FrontIndex(); arg_index < argc;
-         ++arg_index) {
-      output_args.push_back(argv[arg_index]);
-    }
-  }
-
-  // Trim and sort the vector.
-  specified_flags->shrink_to_fit();
-  std::sort(specified_flags->begin(), specified_flags->end(),
-            SpecifiedFlagsCompare{});
-  return output_args;
-}
-
-}  // namespace flags_internal
-
-// --------------------------------------------------------------------
-
-std::vector<char*> ParseCommandLine(int argc, char* argv[]) {
-  return flags_internal::ParseCommandLineImpl(
-      argc, argv, flags_internal::ArgvListAction::kRemoveParsedArgs,
-      flags_internal::UsageFlagsAction::kHandleUsage,
-      flags_internal::OnUndefinedFlag::kAbortIfUndefined);
-}
-
-ABSL_NAMESPACE_END
-}  // namespace absl