Export of internal Abseil changes

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00f5301405423005d9129935c05f20155536cc1a by CJ Johnson <johnsoncj@google.com>:

Removes usage of std::aligned_storage from Abseil implementation details

PiperOrigin-RevId: 296492301

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fc11d15f91764612fba080669d2381dc181df52b by Abseil Team <absl-team@google.com>:

Fix absl::bind_front documentation.

PiperOrigin-RevId: 296482945

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0164c595c129c46bf21ae74eba5399a1da5f140b by Gennadiy Rozental <rogeeff@google.com>:

Automated g4 rollback of changelist 296320700.

PiperOrigin-RevId: 296439968

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1eb295700758ca0894d872b2de7c675b4ad679af by Abseil Team <absl-team@google.com>:

Removes duplicate comments.

PiperOrigin-RevId: 296433214

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c30c01caae02d2fa4ef783d988de6bebb9757c39 by Derek Mauro <dmauro@google.com>:

Merge GitHub #621: Add RISCV support to GetProgramCounter()

Fixes #621

PiperOrigin-RevId: 296351174

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95d4498167596fd7543e025bdfe9a8da9e2ca3c8 by Abseil Team <absl-team@google.com>:

Automated g4 rollback of changelist 296320700.

PiperOrigin-RevId: 296348701

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b193f0543e0cec54dddb2ed51f45dc489c8d06d5 by Gennadiy Rozental <rogeeff@google.com>:

Change TryParse interface to return managed value.

In addition introduce companion StoreValue routine which consumes pointer to source value and stores the value inside of FlagImpl. In a follow up CL we will change StoreValue implementation to behave differently depending on "value storage kind".
We also rename default_src_ to default_value_.

PiperOrigin-RevId: 296320700

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57e942b485d12912a0a8d0d0b35fa2a62847020f by Derek Mauro <dmauro@google.com>:

Merge GitHub #622
 * Add missing #ifdef conditionals for ABSL_HAVE_VDSO_SUPPORT

PiperOrigin-RevId: 296272830
GitOrigin-RevId: 00f5301405423005d9129935c05f20155536cc1a
Change-Id: I1b05eeaf1280f95fb0a2c5f3654995a87c792893

1 files changed, 22 insertions, 4 deletions

diff --git a/absl/functional/bind_front.h b/absl/functional/bind_front.h
index 8448d7b3..5b47970e 100644
--- a/absl/functional/bind_front.h
+++ b/absl/functional/bind_front.h
@@ -38,9 +38,7 @@ ABSL_NAMESPACE_BEGIN
 
 // bind_front()
 //
-// Binds the first N arguments of an invocable object and stores them by value,
-// except types of `std::reference_wrapper` which are 'unwound' and stored by
-// reference.
+// Binds the first N arguments of an invocable object and stores them by value.
 //
 // Like `std::bind()`, `absl::bind_front()` is implicitly convertible to
 // `std::function`.  In particular, it may be used as a simpler replacement for
@@ -140,7 +138,9 @@ ABSL_NAMESPACE_BEGIN
 //
 // Example: Storing bound arguments by reference.
 //
-//   void Print(const string& a, const string& b) { LOG(INFO) << a << b; }
+//   void Print(const std::string& a, const std::string& b) {
+//     std::cerr << a << b;
+//   }
 //
 //   std::string hi = "Hello, ";
 //   std::vector<std::string> names = {"Chuk", "Gek"};
@@ -152,6 +152,24 @@ ABSL_NAMESPACE_BEGIN
 //   // dangling references.
 //   foo->DoInFuture(absl::bind_front(Print, std::ref(hi), "Guest"));  // BAD!
 //   auto f = absl::bind_front(Print, std::ref(hi), "Guest"); // BAD!
+//
+// Example: Storing reference-like types.
+//
+//   void Print(absl::string_view a, const std::string& b) {
+//     std::cerr << a << b;
+//   }
+//
+//   std::string hi = "Hello, ";
+//   // Copies "hi".
+//   absl::bind_front(Print, hi)("Chuk");
+//
+//   // Compile error: std::reference_wrapper<const string> is not implicitly
+//   // convertible to string_view.
+//   // absl::bind_front(Print, std::cref(hi))("Chuk");
+//
+//   // Doesn't copy "hi".
+//   absl::bind_front(Print, absl::string_view(hi))("Chuk");
+//
 template <class F, class... BoundArgs>
 constexpr functional_internal::bind_front_t<F, BoundArgs...> bind_front(
     F&& func, BoundArgs&&... args) {