Export of internal Abseil changes

--
b2a781121ff72fb485b7e67539d5e4ff1eb66df2 by Gennadiy Rozental <rogeeff@google.com>:

Consistently use absl::flat_hash_map instead of std::map in Flags implementation.

PiperOrigin-RevId: 377132816

--
9ab83a154d8f22d51fed0092bf94245b5af1f498 by Derek Mauro <dmauro@google.com>:

Workaround for MSAN being unable to see through getentropy().

https://github.com/google/sanitizers/issues/1173

PiperOrigin-RevId: 377097059

--
8d28e921442d1b246c26f3200f21027557c47657 by Greg Falcon <gfalcon@google.com>:

Disable stack_consumption_test in tsan builds.

A recent tsan change broke the way this test-only utility was counting stack usage.

PiperOrigin-RevId: 377053169
GitOrigin-RevId: b2a781121ff72fb485b7e67539d5e4ff1eb66df2
Change-Id: Ib56356f8128f6c083f32b950091f3a56d9e2cd51

1 files changed, 9 insertions, 3 deletions

diff --git a/absl/flags/internal/usage.cc b/absl/flags/internal/usage.cc
index a588c7f7..949709e8 100644
--- a/absl/flags/internal/usage.cc
+++ b/absl/flags/internal/usage.cc
@@ -245,7 +245,7 @@ void FlagsHelpImpl(std::ostream& out, PerFlagFilter filter_cb,
         << XMLElement("usage", program_usage_message) << '\n';
   }
 
-  // Map of package name to
+  // Ordered map of package name to
   //   map of file name to
   //     vector of flags in the file.
   // This map is used to output matching flags grouped by package and file
@@ -273,20 +273,26 @@ void FlagsHelpImpl(std::ostream& out, PerFlagFilter filter_cb,
 
   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) {
+  for (auto& package : matching_flags) {
     if (format == HelpFormat::kHumanReadable) {
       out << package_separator;
       package_separator = "\n\n";
     }
 
     file_separator = "";
-    for (const auto& flags_in_file : package.second) {
+    for (auto& flags_in_file : package.second) {
       if (format == HelpFormat::kHumanReadable) {
         out << file_separator << "  Flags from " << flags_in_file.first
             << ":\n";
         file_separator = "\n";
       }
 
+      std::sort(std::begin(flags_in_file.second),
+                std::end(flags_in_file.second),
+                [](const CommandLineFlag* lhs, const CommandLineFlag* rhs) {
+                  return lhs->Name() < rhs->Name();
+                });
+
       for (const auto* flag : flags_in_file.second) {
         flags_internal::FlagHelp(out, *flag, format);
       }