Release notes for work in progress boost

Version 1.83.0

Thu, 13 Jul 2023 13:20:26 +0000

New Libraries

Compat: A repository of C++11 implementations of standard components added in later C++ standards, from Peter Dimov and contributors.

Updated Libraries

Chrono:
- Remove use of deprecated Boost.Ratio features.
Compat:
- Added latch.hpp, an implementation of std::latch (contributed by Christian Mazakas.)
- Added shared_lock.hpp, a (partial) implementation of std::shared_lock (contributed by Christian Mazakas.)
Core:
- Added support for incomplete types to boost::core::type_name.
- Bit manipulation functions in boost/core/bit.hpp are now constexpr on recent MSVC versions (VS2019 update 5 and later.)
- Added boost::core::byteswap (an implementation of std::byteswap from C++23) to boost/core/bit.hpp.
- Moved the yield primitives sp_thread_pause, sp_thread_yield, sp_thread_sleep from SmartPtr implementation details to boost/core/yield_primitives.hpp.
Flyweight:
- Added smart-pointer syntax to boost::flyweight (operator* and operator-> dereferencing to the underlying value).
- Fixed a situation where the mutex used by simple_locking was not recursive (issue #12).
Math:
- Added Numerical evaluation of Fourier transform of Daubechies scaling functions 921.
- Added logcdf function to statistical distributions 946.
- Added support for C++23's <stdfloat> types 978.
- Fixed various -Wmaybe-uninitialized warnings
- Fixed round and trunc functions for non-representable numbers 968.
- Fixed calculation of mode for F-distribution 976.
- Fixed overflow in beta distribution 977.
- Fixed overflow in hypergeometric distribution 987.
- Fixed calculation of median absolute deviation with non-zero center 997.
Mp11:
- Added an offset/from parameter to mp_from_sequence, mp_iota, mp_iota_c.
- Added mp_value, mp_list_v, mp_rename_v, mp_is_value_list.
- Added value list support to the primitives in <boost/mp11/list.hpp>.
- Added value list support to mp_repeat, mp_fill, mp_at, mp_back, mp_take, mp_pop_back, mp_drop, mp_insert, mp_erase.
Multi-index Containers:
- Updated range insert in non-unique ordered indices to preserve insertion order of equivalent elements (issue #68).
- Serialization now uses std::size_t instead of unsigned long to save and load the size of a multi_index_container (unsigned long is smaller than std::size_t in LLP64 data models). multi_index_container serialization class version has been bumped from 3 to 4 to reflect this change.
Multiprecision:
- Fixed bug in rational adapter division 542.
- Fixed handling of global precsion changes in multi-threaded environments 552.
- Fixed cpp_int::eval_convert_to noexcept specification 555.
Ratio:
- Change default BOOST_RATIO_VERSION to 2.
- Support for BOOST_RATIO_EXTENSIONS is now deprecated and will eventually be removed when Boost.Ratio is implemented in terms of the standard <ratio> header.
Test:
- Added addtional older platforms to CI system (e.g. GCC 4.6)
- Fixed handling of uintptr_t to make sure it is portable on 32-bit systems 353.
- Fixed warnings from -Wdeprecated-copy-dtor and -Wdeprecated-copy-with-user-provided-dtor 375.
- Fixed handling of check_is_close for C++23 <stdfloat> types 382.
Timer:
- Remove dependency on Boost.Chrono, Boost.System, and others.
- Disable deprecated headers unless BOOST_TIMER_ENABLE_DEPRECATED is defined.
Unordered:
- Major update.
- Added boost::concurrent_flat_map, a fast, thread-safe hashmap based on open addressing.
- Sped up iteration of open-addressing containers.
- In open-addressing containers, erase(iterator), which previously returned nothing, now returns a proxy object convertible to an iterator to the next element. This enables the typical it = c.erase(it) idiom without incurring any performance penalty when the returned proxy is not used.
Variant2:
- Added uses_double_storage().

Updated Tools

Build:
- Includes release of B2 version 4.10.1.

Compilers Tested

Boost's primary test compilers are:

Linux:
- Clang, C++03: 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++11: 3.4, 11.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++14: 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 5.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++17: 6.0.1, 7.0.0, 8.0.0, 9.0.0, 10.0.0, 11.0.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++20: 11.0.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- GCC, C++03: 4.6.3, 11, 12
- GCC, C++11: 4.7.3, 4.8.5, 11, 12
- GCC, C++14: 5.4.0, 6.4.0, 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++17: 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++20: 8.0.1, 9.1.0, 10, 11, 12
OS X:
- Apple Clang, C++03: 11.0.3
- Apple Clang, C++11: 11.0.3
- Apple Clang, C++14: 11.0.3
- Apple Clang, C++17: 11.0.3
- Apple Clang, C++20: 11.0.3
Windows:
- Visual C++: 10.0, 11.0, 12.0, 14.0, 14.1, 14.2, 14.3

Acknowledgements

Marshall Clow and Glen Fernandes managed this release.

Version 1.82.0

Fri, 14 Apr 2023 03:08:20 +0000

Known Issues

These are patches from library authors which were found too late to be fixed in the release.

Filesystem
- Compilation on OpenBSD may fail because of broken support for -Wl,--no-undefined compiler flag for shared libraries on this platform, see #283. Patch.
- On Windows, creating directory iterators over directories in SMBv1 shares may fail with ERROR_INVALID_LEVEL error code, see #284. Patch.

Notice of Dropping C++03 Support

The following libraries will be dropping C++03 support in release 1.84, two releases from now:

Align
Any
Asio
Atomic
Bind
Chrono
ContainerHash
Conversion
DLL
Endian
Filesystem
Function
Functional
Io
LexicalCast
Log
Random
Ratio
SmartPtr
System
Stacktrace
Thread
Timer
TypeIndex
Typeof
Unordered
Variant

This release (1.82) and the next (1.83) will be the last releases offering C++03 support for the above libraries and most of their dependencies.

The new baseline requirement for the above libraries, and for most of Boost, will be C++11. Since old compiler versions often implement C++11 only partially, due to missing support or bugs, what compilers are considered to meet the C++11 requirement may vary by library.

However, a general rule is that if a compiler does not recognize a C++11 keyword or syntax at all (e.g. use of noexcept, use of constexpr, or defining a =deleted function results in an immediate compile error), or if a compiler does not provide a required C++11 header at all (e.g. trying to include <atomic> or <chrono> fails), or the compiler provides a C++11 feature or a header that is completely unusable, this compiler is not considered a C++11 compiler.

This rules out, for instance, Microsoft Visual C++ before 14.0, or GCC before 4.8.

New Libraries

Mysql: a C++11 client for the MySQL database server, based on Boost.Asio, from Ruben Perez.

Updated Libraries

Any:
- Now uses core/enable_if.hpp header instead of the deprecated utility/enable_if.hpp. Thanks to Michael Ford for the PR PR#25.
Asio:
- Added the ability to customise the execution of a completion handler when an operation completes immediately.
- Added user-defined literals for buffer types.
- Added a new protocol type local::seq_packet_protocol to represent AF_UNIX with SOCK_SEQPACKET.
- Exposed sigaction() flags via an optional argument to signal_set::add.
- Change allocator_binder, executor_binder, and cancellation_slot_binder to support detection of unspecialised associators.
- Fixed ambiguity in associated_cancellation_slot<reference_wrapper>::get().
- Fixed awaitable<> handling for completion signatures containing std::exception_ptr.
- Fixed experimental::channel<> try_send failure after a cancel.
- Fixed thread_pool::join() deadlock when the pool has no internal threads.
- Fixed pipe release() when using io_uring.
- Fixed data initialisation and cleanup issues in the io_uring backend.
- Fixed a dangling reference issue in the execution context overload of get_associated_executor().
- Ensured buffered messages can still be received when an experimental::channel<> is closed.
- Fixed the any_completion_handler assignment operator.
- Constrained the constructor of any_completion_handler to prevent accidental copying
- Changed to use uint64_t for OpenSSL options, to match OpenSSL 3.
- Fixed deferred interoperability with multiple completion signatures.
- Fixed channels to add partial support for C++11 and C++14.
- Added missing handler tracking source location support to co_composed and 'awaitable<>' coroutines, when awaiting packaged asynchronous operations.
- Fixed some 'potential null dereference' and shadow variable warnings.
- Fixed a asio::buffer overload selection when used with const_buffers_1 and mutable_buffers_1.
- Disabled the runtime check for current Windows version unless targeting older Windows.
- Fixed compatibility between buffered stream wrappers and move-constructible streams, such as ssl::stream<>.
- Fixed basic_socket_acceptor::async_accept compatibility with lambdas that have a deduced return type.
- Fixed as_tuple compatibility with legacy completion tokens.
- Fixed redirect_error compatibility with new completion tokens.
- Fixed a potential, Windows-specific program termination due to exceptions that should have been allowed to escape from a destructor.
- Prevented inadvertent co_await of boolean expressions.
- Fixed result handling and support for custom allocators in experimental::use_coro.
- Fixed variadic template emulation for is_async_operation and completion_signature_of.
- Fixed incorrect reuse of a moved-from result in experimental::promise.
- Fixed experimental::coro use with custom allocators.
- Fixed seek_cur behaviour with stream-oriented files on Windows.
- Various additions and modifications to the documentation.
- Consult the Revision History for further details.
Atomic:
- When compiled for x86 targets supporting AVX, vector instructions are now used for 128-bit atomic loads and stores.
- For 32-bit x86 targets, 64-bit atomic loads and stores with memory_order_seq_cst semantics will now issue a memory ordering instruction.
- Removed atomic<T>::storage() accessors and atomic<T>::storage_type types that were deprecated in Boost.Atomic 1.73. Users are recommended to use atomic<T>::value() and atomic<T>::value_type instead.
Beast:
- Add error_codes use source_location
- tcp_stream uses the correct executor of the timer.
- error_categories use numeric ids
- file_body supports seek
ContainerHash:
- Added an overload of hash_value for std::nullptr_t.
- Added is_tuple_like and an overload of hash_value for tuple-like types.
- Changed string hashing to use mulxp1_hash. This improves both quality and speed.
Core:
- Added boost/core/snprintf.hpp header with portable definitions of snprintf, vsnprintf and their wchar_t counterparts.
- Deprecated boost/core/is_same.hpp and boost::core::is_same. The header will be removed in a future release. Users are advised to use Boost.TypeTraits or C++ standard library type traits instead.
- Marked boost::ref member functions and associated methods with noexcept.
- Marked boost::swap function with noexcept, depending on whether the type supports a non-throwing swap operation.
- Added boost::core::launder, a portable implementation of std::launder.
- Added BOOST_CORE_ALIGNOF, a portable implementation of alignof.
- Added boost::core::max_align_t, a portable equivalent of std::max_align_t, and boost::core::max_align, the alignment of max_align_t.
- Added boost::core::memory_resource, a portable equivalent of std::pmr::memory_resource from C++17.
- Added boost/core/serialization.hpp, a collection of primitives allowing libraries to implement Boost.Serialization support for their types without including a Serialization header and thereby making their libraries depend on Serialization.
- Added boost::data, an implementation of std::data.
- Added boost::size, an implementation of std::size.
- Updated boost::span to use boost::data which adds support for range construction from an std::initializer_list.
- Added boost::identity, an implementation of std::identity. This facility has been moved from Boost.Functional.
DLL:
- Avoid implicit cast from size_t to uint32_t, thanks to Travers Biddle for the PR PR#57.
Filesystem:
- Fixed compilation errors that could have been caused by path conversion constructors being too permissive on the accepted arguments. (#273)
- v4: path::remove_filename now presesrves the trailing directory separator. (#271)
- Added path::remove_filename_and_trailing_separators, which removes the filename and directory separators preceding it from the path. This behavior is similar to path::remove_filename in Filesystem v3, but is also usable in v4.
- Added path::replace_filename, which replaces filename in a path.
- Updated implementation of the library version selection to avoid ODR violations. (#279)
- On Windows, added a workaround for querying file attributes for files in SMBv1 shares. Previously, directories in SMBv1 shares could have been reported as regular files. This does not affect SMBv2 or later. (#282)
Geometry:
- Major improvements
  - PR#1045 Support geographic buffer for (multi)linestrings and (multi)polygons
- Improvements
  - PR#1114 Comparable distance: Add support for dynamic geometries
  - PR#1046 Support covered_by() for box, geometry combinations
- Solved issues
  - #705 WKT: allow tabs and new lines
  - #1109, #1108 Fixes for union
  - Various fixes in examples
- Breaking changes
  - The WKT output presentation of an empty polygon is now POLYGON() to make it consistent with other geometries
Histogram:
- Replace detail::span and detail::make_span with implementations in boost::core
- Documentation improvements
- Protect usage of std::min and std::max in some cases, contributed by Han Jiang (min,max macros are illegially set by popular Windows headers so we need to work around)
- Added test to catch usage of unprotected min,max tokens in the library in the future
- Fixes to support latest clang-14 and deduction guides in gcc-11+
JSON:
- set_at_pointer.
- boost::hash support.
- Caller-provided serializer storage.
- value_to supports missing elements for std::optional.
- Fix parser suspend inside an escape character.
- Make sentinel() return a unique pointer.
Locale:
- get_system_locale and dependents will now correctly favor LC_ALL over LC_CTYPE as defined by POSIX PR#144
- utf8_codecvt::out returns partial for trailing (UTF) surrogates
- Add boost::locale::util::locale_data to parse a locale
- boost::locale::info::encoding() result is now in uppercase as documented, e.g. "UTF-8" instead of "utf-8"
- Support M49 country codes such as en_001 or en_150 PR#148
- Treat en_US_POSIX as an alias for the C locale PR#148
- Improve error for missing segmentation support (i.e. without ICU) PR#149
- Fix compiler warnings
Math:
- Deprecated C++11 support: We now require C++14 as a minimum standard. Our minimum tested compiler versions are now Clang-5, GCC-5 or MSVC-14.1.
- Added Estrin's method for polynomial evaluation.
- Fix various issues in non-central distributions to allow for larger non-centralities see 939.
- Added CMake install target.
- Fix special_functions.hpp to disable anything which can't be used in an exception-free environment.
- Get condition number calculation working in C++14.
- Fix constexpr table driven functions to avoid massive slowdown when the code is not actually constexpr, see 923.
- Improve tanh_sinh boundary handling, see 894.
- Add Linux arm64, s390x and Apple M1 testing, fix up test cases to handle 128-bit long doubles.
- Improve constexpr math functions to better handle infinities and NaN's.
- Make the integrators const-correct.
- Fix tanh_sinh integrator in case the function underflows, see 898.
- Don't use std::cbrt as some platforms still don't support it.
- Stop non-central T from raising spurious FE_INVALID exceptions, see 892.
- Fix binomial distribution edge case.
- Improve ibeta handling of very small arguments, see 884.
- Improve ibeta handling of infinities and NaN's, see 878.
- Improve error handling in powm1, see 781.
- Improve root-finder bracketing to bracket faster when the exponent is super-large or small.
- Fix root finding edge cases, see 873.
- Lots of miscellaneous warning fixes.
- Add assertions when using features which require C++17 for better error messages when invoking the compiler in a lower std version.
Multi-index Containers:
- Serialization now uses unsigned long instead of collection_size_type, and multi_index_container serialization class version has been bumped from 2 to 3 to reflect this change. Reading old archives may fail for custom archive types giving special treatment to collection_size_type values: if this is the case, globally define the macro BOOST_MULTI_INDEX_ENABLE_SERIALIZATION_COMPATIBILITY_V2 to ensure backwards compatibility in reading operations.
- Maintenance work.
Multiprecision:
- Deprecated C++11 support: We now require C++14 as a minimum standard. Our minimum tested compiler versions are now Clang-5, GCC-5 or MSVC-14.1.
- Added a new forward declaration header.
- Update Eigen interoperability so we no longer rely on Eigen's details, see 479.
- Add Cmake install target.
- Fix cpp_dec_float construction from string in standalone case for better error handling, see 499.
- Remove redundent definitions when in C++17 mode, see 530.
- Fix the error handling in standalone itrunc and ltrunc.
- Fix potentially uninitialized storage when parsing octal strings.
- Add arm64 and s390x CI testing.
- Add some missing expression template unpacking code for powm, see 506.
Nowide:
- Add convert_string overload accepting a (std::)string instance
- Add quoted to output (quoted UTF-8) paths (std::filesystem or boost::filesystem) to streams PR#170
PFR:
- Implemented the boost::pfr::is_implicitly_reflectable and the machinery for specializing aggregates as reflectable or not, thanks to Denis Mikhailov for the PR PR#111.
- Implemented boost::pfr::get by type of an element in the aggregate.
- Implemented the BOOST_PFR_ENABLED macro to detect library support for reflection, thanks to Denis Mikhailov for the PR PR#86.
- Fixed missing terminating character, thanks to Denis Mikhailov for the PR PR#114.
- Fixed the boost/pfr/config.hpp compilation on older compilers, thanks to Denis Mikhailov for the PR PR#118.
- Workaround for broken C++17 stuctured binding in old compilers, thanks to Denis Mikhailov for the PR PR#119.
- Avoid -Wzero-as-null-pointer-constant warnings, thanks to Markus F.X.J. Oberhumer for the PR PR#117.
- Fixed multiple typos, thanks to Denis Mikhailov for the fixes.
- Added missing #pragma once, thanks to caozhanhao for the PR PR#121.
- Multiple fixes and improvements for the docs.
Process:
- Added management for extern processes to V2 (still experimental)
- Deprecated wait_for & wait_until in V1 - they will be removed in the future!
Stacktrace:
- Fixed typos in docs and comments, thanks to Chocobo1 for the PR PR#132.
- Fixed multithreading flag detection for backtrace_create_state if BOOST_STACKTRACE_BACKTRACE_FORCE_STATIC is defined.
StaticString:
- Boost.Core string_view and std::string_view interoperability
Test:
- Fixed several unused variable warnings
- Fixed sprintf deprecation warnings
- Fixed undefined behavior in basic_cstring::rfind
- Added CI through Github Actions
Unordered:
- Major update.
- Added node-based, open-addressing containers boost::unordered_node_map and boost::unordered_node_set.
- Extended heterogeneous lookup to more member functions as specified in P2363.
- Replaced the previous post-mixing process for open-addressing containers with a new algorithm based on extended multiplication by a constant.
- Fixed bug in internal emplace impl where stack-local types were not properly constructed using the allocator of the container which breaks uses-allocator construction.
URL:
- Add url::format with automatic percent-encoding
- URL router example
- set_params convenience function
- Support implicit conversions to string_view
- Parsing constructors are implicit
- string_token::arg has virtual destructor and slice protection
- Support BOOST_URL_DISABLE_THREADS
- Improvements and Bug fixes:
  - WIN32_LEAN_AND_MEAN macro redefinition warning
  - Comparison differentiates absent and empty components
  - Detect hier_part_rule with empty-port-like segments
  - Segments comparison as if normalized works above root
  - hier-part path-rootless considers invalid segments
  - port as number is set to 0 when it overflows
  - ipv4 to string overflow detection algorithm
Variant:
- Now uses core/addressof instead of the deprecated utility/addressof. Thanks to Michael Ford for the PR PR#105.

Updated Tools

Build:
- Includes release of B2 version 4.9.4.

Compilers Tested

Boost's primary test compilers are:

Linux:
- Clang, C++03: 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++11: 3.4, 11.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++14: 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 5.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++17: 6.0.1, 7.0.0, 8.0.0, 9.0.0, 10.0.0, 11.0.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++20: 11.0.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- GCC, C++03: 4.6.3, 11, 12
- GCC, C++11: 4.7.3, 4.8.5, 11, 12
- GCC, C++14: 5.4.0, 6.4.0, 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++17: 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++20: 8.0.1, 9.1.0, 10, 11, 12
OS X:
- Apple Clang, C++03: 11.0.3
- Apple Clang, C++11: 11.0.3
- Apple Clang, C++14: 11.0.3
- Apple Clang, C++17: 11.0.3
- Apple Clang, C++20: 11.0.3
Windows:
- Visual C++: 10.0, 11.0, 12.0, 14.0, 14.1, 14.2, 14.3

Acknowledgements

Marshall Clow and Glen Fernandes managed this release.

Version 1.81.0

Wed, 14 Dec 2022 17:44:48 +0000

New Libraries

URL: A library for parsing, modifying, and printing URLs using only C++11, from Vinnie Falco and Alan de Freitas. Features include fast compilation, strong invariants, and strict compliance using a memory-friendly approach.

Updated Libraries

Asio:
- Added the consign completion token adapter, which can be used to attach additional values to a completion handler.
- Added any_completion_handler<>, which can be used to type-erase completion handlers.
- Added experimental::co_composed to enable lightweight implementations of user-defined asynchronous operations using C++20 coroutines.
- Add range-based experimental::make_parallel_group() overloads.
- Added any_completion_executor, a type-erased wrapper for executors that are associated with completion handlers.
- Added missing context query to use_future's executor.
- Added nothrow constructor overloads to execution::any_executor<> and any_io_executor.
- Optimised representation of empty execution::any_executor objects to improve the performance of copy and move operations.
- Added an associated_cancellation_slot specialisation for std::reference_wrapper.
- Changed I/O objects to return their executors by const reference.
- Changed associated to use deduced return types for all two-argument get functions.
- Fixed spawn implementation to catch unhandled exceptions and rethrow them outside of the spawned "thread".
- Fixed spawn to ensure the completion handler is dispatched through the correct executor.
- Fixed cleanup of of terminal-state spawn "thread" objects.
- Fixed spawn and co_spawn implementations to dispatch cancellation handlers on the correct executor.
- Changed semantics of 'dispatch' to mean the executor is used as-is.
- Deprecated the execution::execute customisation point and sender/receiver facilities.
- Added a C++11 parallel_group example.
- Fixed example code to not use the deprecated resolve conversions.
- Fixed an ambiguity in experimental::channel_traits specialisations.
- Added a specialised channel implementation for the for R(error_code) signature.
- Made cancelled() public on the async_compose 'self' object.
- Added io_executor_type and get_io_executor to the async_compose 'self' object.
- Fixed implementation of release() for Windows overlapped handles.
- Enabled deferred awaiting for experimental::coro, regularised experimental::use_coro, and fixed allocator handling.
- Cleaned up experimental::promise and made it an asynchronous operation object.
- Constrained post/defer overloads on ability to require blocking.never.
- Changed descriptor implementation to fall back to fcntl if ioctl fails with ENOTTY when setting non-blocking mode.
- Fixed Xcode deprecation warnings related to use of sprintf.
- Fixed the arguments passed to select_reactor::run when it is run on an internal thread.
- Fixed compilation errors when BOOST_ASIO_DISABLE_SMALL_BLOCK_RECYCLING is defined.
- Updated detection of C++20 coroutine support on clang 14 and later.
- Changed standard library feature detection to always enable std::invoke_result when targeting C++17 or later.
- Fixed detection of return type deduction with MSVC.
- Updated the asynchronous operation requirements to relax the requirements on the associated executor.
- Added io_uring to the implementation notes.
- Consult the Revision History for further details.
Beast:
- Add buffers_generator
- Add beast::http::message_generator
- Added buffer_ref, so beast buffers can be used with asio.
- Support for per-operation cancellation
- C++20 awaitable examples.
- websocket per-message compression options
- websocket timeout option api
- multiple content length error
- Support for default-completion and rebind
Container Hash:
- Major update.
- The specializations of boost::hash have been removed; it now always calls hash_value.
- Support for BOOST_HASH_NO_EXTENSIONS has been removed. The extensions are always enabled.
- All standard containers are now supported. This includes std::forward_list and the unordered associative containers.
- User-defined containers (types that have begin() and end() member functions that return iterators) are now supported out of the box.
- Described structs and classes (those annotated with BOOST_DESCRIBE_STRUCT or BOOST_DESCRIBE_CLASS) are now supported out of the box.
- hash_combine has been improved.
- The performance (and quality, as a result of the above change) of string hashing has been improved. boost::hash for strings now passes SMHasher in 64 bit mode.
- The documentation has been substantially revised to reflect the changes.
Core:
- empty_value members are now marked as constexpr.
- Added fclose_deleter, a deleter that calls std::fclose on a pointer to std::FILE.
- Bit manipulation utilities in boost/core/bit.hpp now explicitly require unsigned integers on input. (#129)
- bit_width now returns int instead of a value of the input argument type. This follows resolution of LWG3656.
Describe:
- To allow the inclusion of enumerators.hpp, bases.hpp, and members.hpp when the option -pedantic is used, the invocation of BOOST_DESCRIBE_ENUM has been moved from modifiers.hpp into a separate header, modifier_description.hpp. As a consequence, modifiers.hpp no longer includes enum.hpp. Code that has been relying on this implicit inclusion may fail, and will need to be fixed to include enum.hpp.
DLL:
- Fixed path_from_handle implementation for Windows platforms, thanks to @SaltfishAmi for the bug report 57.
Filesystem:
- Deprecated: path construction, assignment and appending from containers of characters, such as std::vector<char> or std::list<wchar_t>, is deprecated in v3 and removed in v4. Please use string types or iterators instead.
- Deprecated: boost/filesystem/path_traits.hpp header is deprecated and will be removed in a future release. The header contained implementation details of path and should not be used in user's code.
- Previously deprecated APIs will now generate compilation warnings on use. To suppress these warnings, BOOST_FILESYSTEM_ALLOW_DEPRECATED macro can be defined when compiling user's code.
- Fixed compilation due to a missing include on POSIX systems that do not support *at APIs. (#250)
- On Windows prior to 10, added a workaround for network share filesystem that produces ERROR_INVALID_PARAMETER when constructing directory iterators. (PR#246, #245)
- On Windows, fixed weakly_canonical failing with an ERROR_INVALID_FUNCTION error code if the path started with the "\\?\" prefix. (#247)
- Added support for std::string_view, boost::string_view and boost::container::string (as well as respective wchar_t counterparts) in path constructors, assignment and appending operations. (#208)
- path constructors, assignment and appending operations taking a pair of iterators will no longer accept iterators with value types that are not one of the supported path character types.
- On Windows, improved compatibility of directory_iterator with various mounted filesystems and Wine releases prior to 7.21. (#255, #266)
- On Windows, deduplicated files are now reported as regular files rather than reparse files. (#262)
Fusion:
- Added fusion::identity_view (PR#240)
- Added support for associative sequences on fusion::transform_view (PR#239)
- Fixed compilation for the case when fusion::reverse_view used with an associative sequence (PR#237)
- Fixed Clang 13 -Wdeprecated-copy warnings (PR#261)
- A small dependency reorganization. Now boost::ref and boost::noncopyable are used from Boost.Core (PR#249)
- Added CI testing on Linux and MacOS for clang and gcc, fixed CI testing on Windows (PR#245, PR#236)
- Improved docs and fixed typos (#234, PR#235, PR#238)
Geometry:
- Solved issues
  - #1048 Index: Fix dangling references when Indexable is returned by value by IndexableGetter
  - #1076 Union: in rare cases it might miss one polygon
  - #1081 Union: due to precision it might miss interior rings
- Bugfixes
  - #1063 Intersection: fix a bug in intersection of simple spherical polygons
  - #1064 Formulas: fix a consistency issue in geodesic direct formulas
  - #1088 Point: Fix regression for custom point types
  - Various fixes for missing include files, warnings, C++20 compilation errors and documentation
Histogram:
- Major update.
- Added new accumulators::fraction to compute fractions, their variance, and confidence intervals
- Added interval computers for fractions: utility::clopper_pearson, utility::wilson_interval, utility::jeffreys_interval, utility::wald_interval which can compute intervals with arbitrary confidence level
- Added utility::confidence_level and utility::deviation types to pass confidence levels as probabilities or in multiples of standard deviation for all interval computers, respectively
- Fixed internal sub_array and span in C++20
Iterator:
- function_output_iterator now supports perfect forwarding of the assigned values to the wrapped function object. (PR#73)
- Fixed compilation of constructing a function_input_iterator from result of post-incrementing another function_input_iterator. (#75)
- The result of post-incrementing an iterator based on iterator_facade now supports operator->. (it++)->foo is equivalent to (*it++).foo, which was supported before.
JSON:
- Added object::stable_erase.
- Added parse overload for std::istream and operator>> for value.
- Added rvalue ref-qualified accessors for value.
- Conversion traits were redesigned.
- Added conversion support for described classes and enums, std::optional, std::variant, and null-like types (including std::nullptr_t, std::nullopt_t, and std::monotype).
- Added non-throwing conversion from value to user types.
LexicalCast:
- Fixed compilation while casting volatile arithmetic types. Thanks to Giovanni Cerretani for the bug report #50.
- Removed usage of deprecated headers. Thanks to Michael Ford for the PR PR#53.
Locale:
- Major update with some breaking changes.
- C++11 support is now required, support for C++03 and earlier is dropped
- Some enums have been converted to enum classes - Avoids name clashes
- Replace -sICU_LINK_LOCALE & -sICU_LINK by fine-grained configuration options as done in Boost.RegEx
- Fix detection of libiconv allowing Boost.Locale to be build (again) on some platforms
- Remove use of and support for std::auto_ptr
- Make the codecvt using wchar_t on Windows assume/use UTF-16 enconding
- Performance improvements: Make basic_format, date_time & hold_ptr movable, Fix use of format cache
- Make Boost.Locale compatible with more ICU versions (especially the tests)
- Fix RTTI definitions for some classes (visibility issues)
- Fix compatibility of the ICU backend with some libc++ versions
- Fix return value of some operators to correctly return non-const *this
- Fix int-overflow on negative roll of years in date_time
- Handle or suppress many warnings which makes the build log cleaner
- Add support for more Windows codepages
- Fix support for Windows codepages like ISO-2022-JP
Nowide:
- Fix build failure of tests on MSVC
Stacktrace:
- The library does not use COM initialization any more. Thanks to Alex Guteniev for the bug report, clarifications and PR PR#123!
- The library now may use BOOST_STACKTRACE_BACKTRACE_INCLUDE_FILE macro value while detecting the libbacktrace availability in b2, thanks to Ben Gemmill for the bug report #115.
- Added BOOST_STACKTRACE_BACKTRACE_FORCE_STATIC macro to force a single backtrace_state static instance while using the libbacktrace. Thanks to the Rasmus Thomsen for the bug report #118!
- Avoid unresolved references when including only the boost/stacktrace/stacktrace.hpp header. Thanks to the Long Deng for the bug report #116.
- Optimized stacktrace printing by not calling strlen on Windows platforms. Thanks to Alex Guteniev for the bug report #122
PFR:
- Improved detection of aggregate initializables in C++14 mode, thanks to Denis Mikhailov for the PR PR#97.
- Suppress clang-tidy warnings, thanks to Alexander Malkov for the PRs PR#109, PR#104.
- Use fold expressions if they are supported by the compiler. Thanks to Jean-Michaël Celerier for the PR PR#96.
STLInterfaces:
- Fix two ill-formed iterator_interface operators in pre-C++20 iterators with a const value_type.
System:
- The macro BOOST_SYSTEM_DISABLE_THREADS can now be defined to disable the use of <mutex> (e.g. on single-threaded libstdc++).
- Added value_type, error_type, in_place_value, in_place_error to result<>.
- Added emplace to result<>.
Unordered:
- Major update.
- Added fast containers boost::unordered_flat_map and boost::unordered_flat_set based on open addressing.
- Added CTAD deduction guides for all containers.
- Added missing constructors as specified in LWG issue 2713.
Variant:
- Avoid recursive inclusion of headers, thanks to Nathan Sidwell for the bug report #101.
- Removed usage of deprecated headers, thanks to Michael Ford for the PR PR#96.
- Fixed compilation on clang in C++23 mode, thanks to Ed Catmur for the PR PR#98.
Variant2:
- Added support for boost::json::value_from and boost::json::value_to.

Compilers Tested

Boost's primary test compilers are:

Linux:
- Clang: 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++11: 3.4, 11.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++14: 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 5.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++17: 6.0.1, 7.0.0, 8.0.0, 9.0.0, 10.0.0, 11.0.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- Clang, C++20: 11.0.0, 12.0.0, 13.0.0, 14.0.0, 15.0.0
- GCC: 4.6.3, 11, 12
- GCC, C++11: 4.7.3, 4.8.5, 11, 12
- GCC, C++14: 5.4.0, 6.4.0, 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++17: 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++20: 8.0.1, 9.1.0, 10, 11, 12
OS X:
- Apple Clang: 11.0.3
- Apple Clang, C++11: 11.0.3
- Apple Clang, C++14: 11.0.3
- Apple Clang, C++17: 11.0.3
- Apple Clang, C++20: 11.0.3
Windows:
- Visual C++: 10.0, 11.0, 12.0, 14.0, 14.1, 14.2, 14.3

Acknowledgements

Marshall Clow and Glen Fernandes managed this release.

Version 1.80.0

Wed, 10 Aug 2022 21:25:15 +0000

Known Issues

These are patches from library authors which were found too late to be fixed in the release.

Config
- Support for libcpp15 which removes std::unary_function and std::binary_function. Patch.
Filesystem
- Directory iterators may fail to construct for a network share on Windows prior to 10, see PR#246 and #245. Patch.
- On Windows, weakly_canonical fails to process paths that start with the "\\?\" prefix, see #247. Patch.
- On POSIX systems that don't support *at APIs, compilation fails due to a missing include, see #250. Patch.
Unordered
- Containers are not in a valid state after moving, see #139. Patch.
- Fix MSVC /RTCc build runtime failures. Patch.

New Libraries

No new libraries.

Updated Libraries

Asio:
- Added a deduced trailing return type to all asynchronous operations, to enable the new form of async_result for C++11.
- Moved append, prepend, as_tuple, and deferred to the boost::asio namespace, and made them compatible with C++11.
- Made experimental::parallel_group compatible with C++11.
- Added buffer() overloads for contiguous containers, such as std::span.
- Added the ability for awaitable<>-based coroutines to directly co_await operations that are packaged as function objects.
- Changed spawn() to be a completion token-based asynchronous operation, and added support for cancellation. The basic_yield_context token now supports move-only and variadic result types. When targeting C++11 and later, spawn() and basic_yield_context are implemented in terms of Boost.Context directly.
- Added the is_async_operation trait and async_operation concept.
- Added the completion_signature_of trait.
- Added converting move construction/assignment to posix descriptors, serial ports, pipes, Windows object_handle, Windows stream handles, and Windows random-access handles.
- Added release() member functions to pipes, Windows stream handles, and Windows random-access handles.
- Enabled support for Endpoint implementations that return void pointers from their data() member functions, as per the documented Endpoint type requirements.
- Removed all() and race() from experimental::promise, as experimental::parallel_group covers this functionality.
- Added source locations to exceptions and error codes produced by the synchronous and asynchronous operations.
- Fixed compatibility with OpenSSL 3.0.4 and later.
- Fixed compatibility with with -masm=intel.
- Explicitly stated that socket shutdown() calls are thread-safe with respect to certain other synchronous operations on the same socket.
- Optimised the move construction of I/O objects where only the executor type differs.
- Fixed the detection of std::invoke_result for clang/libc++.
- Fixed an issue where experimental::parallel_group initiation incorrectly moved arguments instead of forwarding them.
- Fixed a sequencing issue in the implementation of post(), dispatch(), and defer().
- Fixed the awaitable<> implementation to propagate exceptions from awaited initiation functions through the current completion handler.
- Fixed detection of std::aligned_alloc with gcc 7.
- Changed to avoid using the soon-to-be-deprecated std::aligned_storage on newer compilers.
- Fixed detection of std::aligned_alloc for older Apple platforms.
- Removed faulty assertions from experimental::coro implementation.
- Added defence against Qt-defined macros when building with Intel C++.
- Changed the implementation of the select_reactor, on Windows, to ensure that any exception resulting from failure to recreate its interrupter's sockets will be allowed to propagate out through io_context::run().
- Fixed various compiler warnings.
- Updated all composed operations examples, and the C++11 timeouts example, to use the new async_result form.
- Added composed operation and coroutine examples for C++20.
- Consult the Revision History for further details.
Atomic:
- Improved portability of endianness checks on ARM, AArch32 and AArch64 targets. (#59)
- Fixed compilation with MSVC 14.0 (Visual Studio 2015) in C++17 mode. (#61)
Filesystem:
- On Windows, added a fallback implementation for querying file attributes in case if the file cannot be opened with ERROR_ACCESS_DENIED error. This may allow status and symlink_status to succeed for system files and directories that are not reparse points or symlinks. (#234)
- On Windows, added a workaround for FAT/exFAT filesystems that produce ERROR_INVALID_PARAMETER when querying file attributes. This affected status and symlink_status, which reported that files do not exist, and directory iterators, which failed to construct, as well as other dependent operations. (#236, #237)
- Worked around a compilation problem on RTEMS. (PR#240)
- On Linux, corrected switching to sendfile copy_file implementation if copy_file_range failed with ENOSYS in runtime. The sendfile fallback implementation used to skip the filesystem type check and could fail for some filesystems.
- On POSIX systems supporting openat and related APIs defined in POSIX.1-2008 and on Windows Vista and later, improved protection of remove_all against CVE-2022-21658 that was implemented in the previous release. The previous fix could still result in removing unintended files in certain conditions. Other systems remain vulnerable.
GIL: NOTICE: We are planning BREAKING switch to C++17 as minimum required C++ language version in one or two releases after Boost 1.80 (#676)
- Added
  - GSoC 2020: Added Perona-Malik anisotropic diffusion algorithm (PR#500)
  - GSoC 2020: Added histogram class and related functionality (PR#499)
  - GSoC 2020: Added histogram equalization feature (PR#514)
  - GSoC 2020: Added histogram matching algorithm (PR#515)
  - GSoC 2020: Added ability to stack images either horizontally (hstack) or vertically (vstack) (PR#506)
  - GSoC 2020: Added adaptive histogram equalization algorithm (PR#516)
  - GSoC 2020: Added Standard Hough Transform and circle rasterization (PR#512)
  - GSoC 2020: Added Bresenham's algorithm for line rasterization (PR#512)
  - GSoC 2021: Added rotation of image by arbitrary angle around its center (PR#565)
  - GSoC 2021: Added rasterization support for ellipse based on "An Efficient Ellipse-Drawing Algorithm" by Jerry Van Aken (PR#585)
  - Added image constructor from compatible view (PR#520)
  - Added inverse function for affine matrix3x2 (PR#527)
  - Added standard morphological transformations (PR#541)
  - Added for_each_pixel overload for any_image (PR#648)
  - Added C++17 polymorphic memory resource typedefs for image class (PR#529)
- Changed
  - BREAKING: The required minimum C++ version is changed from from C++11 to C++14. Currently, large parts of GIL still compile with a C++11 compiler. However, there is no guarantee that it stays that way, and any compilers that do not support at least C++14 are considered unsupported as of now.
  - BREAKING: any_color_converted_view() is deprecated and will be removed in the next release. Use color_converted_view() instead, which provides the same feature.
  - BREAKING: apply_operation for any_image is deprecated and will be removed in the next release. Use variant2::visit instead, which provides the same feature. (PR#656)
  - Moved numeric extension to core (PR#573)
  - Added support for C++17's <filesystem> (PR#636) The availability of the std::filesystem is detected automatically, unless the BOOST_GIL_IO_USE_BOOST_FILESYSTEM macro is defined that forces the preference of the Boost.Filesystem.
  - Renamed pixel_multiply_t to pixel_multiplies_t and pixel_divide_t to pixel_divides_t (PR#655)
  - Renamed io/dynamic_io_new.hpp to io/detail/dynamic.hpp (PR#653)
  - Moved function construct_matched into boost::gil::detail namespace as it was only used by other implementation details (PR#653)
  - Made packed_pixel trivially copyable and assignable (PR#679)
  - Replace deprecated libtiff v4.3 typedefs with C99 fixed-size integers (PR#685)
- Removed
  - BREAKING: Removed support for GCC 5 (PR#572)
  - Removed deprecated.hpp (PR#627)
- Fixed
  - Fixed conversion from RGB to HSL (PR#505)
  - Fixed conversion from RGB to signed CMYK (PR#522)
  - Removed unnecessary numeric cast in hsv.hpp (PR#530)
  - Fixed default constructor for homogeneous_color_base for reference pixel elements (PR#542)
  - Fixed returning reference to local temporary object in subchroma_image_view (PR#556)
  - Added missing header guards in diffusion.hpp (PR#568)
  - Fixed any_image_view<>::const_t (PR#526)
  - Fixed C++20 incompatibilities in I/O extensions (PR#617)
  - Ensured all examples build without errors (PR#628)
  - Fixed convolve_2d for images with float32_t channel model (PR#577)
  - Fixed for_each_pixel for non-1d iterable views (PR#621)
  - Fixed: is_equal_to_sixteen in PNG I/O was less-than test (PR#650)
  - Re-allow devicen_t with two components (PR#654) It was unintentionally removed in Boost 1.72
  - Fixed memory leak in image class for empty dimensions (PR#649)
- Acknowledgements
  - Cypre55, Samuel Debionne, Mike-Devel, Edward Diener, Peter Dimov, Omar Emara, Dhruva Gole, Nicolas Herry, Eugene K, Avinal Kumar, Gaurav Kumar, Marco Langer, Pranam Lashkari, Mateusz Łoskot, Giovanni Mascellani, Debabrata Mandal, Gopi Krishna Menon, René Ferdinand Rivera Morell, Felix Morgner, Harshit Pant, Paul92, André Schröder, Scramjet911, Siddharth, Dirk Stolle, Prathamesh Tagore, theroyn, Olzhas Zhumabek
Graph:
- Bug fixes:
  - Fix bug in stoer_wagner_min_cut where vertices are not merged at the end of each mincut phase (#286)
  - Fix conversion warning for return type of strong_components (#293)
  - Fix compilation failure of boykov_kolmogorov_max_flow named parameter overload (#232)
- General code improvements:
  - Remove redundant call to combine in astar_search_no_init_tree (#260)
  - Remove redundant child_idx argument of d_ary_heap_indirect<>::child (#261)
  - Improve documentation for traversal categories (#303)
- Acknowledgements
  - Viktor Pti, Sebastian Brockmeyer, Etienne dg
Histogram:
- Fixed segfault in indexed when trying to iterate over histogram with axes of zero size (physical or logical) under certain conditions
- Removed previously deprecated API
  - class accumulators::thread_safe: use accumulators::count<T, true>
  - Methods accumulators::sum::large and accumulators::sum::small: use accumulators::sum::large_part and accumulators::sum::small_part
  - Type alias algorithm::reduce_option: use algorithm::reduce_command
  - Template function axis::traits::static_options: use axis::traits::get_options
  - Template function axis::traits::static_is_inclusive: use axis::traits::is_inclusive
  - Type alias indexed::range_iterator: use indexed::iterator
  - Type alias indexed::accessor::reference: use indexed::accessor::const_reference
Iterator:
- For C++11 and later, added support for perfect forwarding of values written to function_output_iterator. (PR#73)
- Added protection against writing to function_output_iterator a result of dereferencing another function_output_iterator.
JSON:
- Added non-const value::at overloads.
- Added the ability to manually choose endianness of the platform.
- Added string::subview() overload.
- Fixed segfault in array::erase(it).
- Fixed low performance of serialize on libc++.
- Fixed ambigious conversion to std::string_view on GCC 8.
- Fixed parsing on big-endian platforms.
- Fixed handling of comment after trailing comma.
LEAF:
- API breaking change: throw leaf::exception(....) now becomes leaf::throw_exception(....)
- Fixed a bug in support for a rare build configuration (exception handling enabled, diagnostics disabled)
- Using nullptr instead of 0 throughout
- Fixed pedantic warnings
Locale:
- Deprecated support for C++03 and earlier, C++11 will be required in the next release
- Provide -sICU_LINK_LOCALE as a temporary replacement for -sICU_LINK which is incompatible with Boost.Regex. -sICU_LINK_LOCALE and -sICU_LINK are deprecated and will be replaced by ICU_*_NAME options to be compatible with Boost.Regex
- Fix UB/assertion failure in the ICU collator implementation when transforming empty strings
- Fix some issues related to visibility of classes in shared libraries (Unix only)
- Fix compatibility with C++20 mode
- Fix compatibility with BOOST_USE_WINDOWS_H
- Fix build failures due to missing includes
- Handle or suppress many warnings which makes the build log cleaner
Log:
- Bug fixes:
  - Fixed binding incorrect local address in UDP socket-based syslog_backend when IPv6 address is used for the syslog server. (#181)
  - Added a workaround for a bug in libstdc++ from gcc 11.2. When max_size_decor was used on a formatting stream, std::codecvt::do_length incorrectly accessed the input buffer and caused a buffer overflow.
- See changelog for more details.
Math:
- Deprecated C++11 support: from 2023 we will require C++14 as a minimum standard. This will mean GCC-5 or MSVC-14.1 as a minimal requirement.
- Add constexpr fma support, see 734.
- Add support for the Chatterjee Correlation Coefficient, see 770.
- Added support for the logarithm of the PDF for all the distributions.
- Improve support for building with no exception or RTTI support.
- Some minor bug fixes for [sub 1]F[sub 1] corner cases, see 778.
Multiprecision:
- Mark C++11 support as deprecated: from 2023 we will move to requiring C++14 as a minimum standard level. That will drop support for GCC versions prior to 5 and MSVC prior to 14.1.
- Fix conflict between boost/cstdfloat.hpp and this library.
- Clean up lots of gcc and clang warnings.
- Fix input streaming of composite types (complex, interval rational) where there is a trailing delimeter in the stream and no whitespace.
- Fix constexpr integer square root where the input is 1, 2 or 3.
- Add missing #include of <memory> to float128.hpp.
- Correct 2-arg constructor for class number to prevent ambiguity in some cases.
- Correct and make more consistent behaviour of divide-by-zero in gmp.hpp.
Multi-index Containers:
- Maintenance work.
Nowide:
- Major performance improvement for Bulk I/O with files
- basic_filebuf: Fix wrong return value of sync when fflush failed
- basic_filebuf: Fix possible undefined behavior in a corner case when nothing was actually written but buffer is in "write" mode
- basic_filebuf: Limit putback of characters (i.e. pbackfail) only allowing putback of buffered characters (may be only 1 character)
Optional:
- Added specializations for std::hash<boost::optional<T>>. This is a breaking change for programs that define such specializations themselves. For more details see specs.
STLInterfaces:
- Fix #53: "missing 'typename' prior to dependent type name 'C::const_iterator'"
- Fix #54: "Concept check fails on .data() of a view on contiguous iterator_interface instantiations"
- New additions to make it easy to write views and view adaptors that work like, and interoperate with, the ones in the standard library:
  - Add workalikes for C++23's std::bind_back() and std::range_adaptor_closure for pre-C++23 code.
  - Add templates closure and adaptor to make writing view adaptors easier, following the examples in P2387.
System:
- When an error_code is converted to std::error_code and then back to error_code, the original is now restored, if possible.
- Reworked the conversion from error_category to std::error_category to avoid the one-time allocation that shows up on leak checkers.
- Added a constructor that allows replacing the source location of an error_code, and a corresponding assign.
- Added a converting constructor to result.
Unordered: Major update:
- Refactor internal implementation to be dramatically faster
- Allow final Hasher and KeyEqual objects
- Update documentation, adding benchmark graphs and notes on the new internal data structures
Utility:
- In string_view/string_ref, fixed max_size returning incorrect value. (#91)
- Removed noexcept specifier from string_view::compare as it may throw on some input arguments. (#94)
- In string_view/string_ref, added support for calling substr with no arguments. (#96)
- Added string_view::contains methods that were introduced in C++23. (#93)
- In string_view, added asserts in remove_prefix/remove_suffix methods to enforce the precondition that the prefix/suffix length does not exceed the string view size. The previous (undocumented) behavior of silently clamping the prefix/suffix length is deprecated and will be removed in a future release. (#92)
Wave: Fixed bugs:
- #24: Line numbers wrong after conditional section
- #160: one test fails with error C2660 and error C2440 under msvc /permissive- mode
- #161: BOOST_WAVE_THROW_NAME_CTX does not result in a context callback and always throws
- #162: When Boost headers are included in the preprocessed translation unit, Wave fails in boost/integer.hpp(99)

Updated Tools

Build:
- Includes release of B2 version 4.9.2.

Compilers Tested

Boost's primary test compilers are:

Linux:
- Clang: 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 12.0.0, 13.0.0, 14.0.0
- Clang, C++11: 3.4, 11.0.0, 13.0.0, 14.0.0
- Clang, C++14: 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 5.0, 12.0.0, 13.0.0, 14.0.0
- Clang, C++17: 6.0.1, 7.0.0, 8.0.0, 9.0.0, 10.0.0, 11.0.0, 12.0.0, 13.0.0, 14.0.0
- Clang, C++20: 11.0.0, 12.0.0, 13.0.0, 14.0.0
- GCC: 4.6.3, 11, 12
- GCC, C++11: 4.7.3, 4.8.5, 11, 12
- GCC, C++14: 5.4.0, 6.4.0, 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++17: 7.3.0, 8.0.1, 9.1.0, 11, 12
- GCC, C++20: 8.0.1, 9.1.0, 10, 11, 12
OS X:
- Apple Clang: 11.0.3
- Apple Clang, C++11: 11.0.3
- Apple Clang, C++14: 11.0.3
- Apple Clang, C++17: 11.0.3
- Apple Clang, C++20: 11.0.3
Windows:
- Visual C++: 10.0, 11.0, 12.0, 14.0, 14.1, 14.2, 14.3

Acknowledgements

Marshall Clow, Michael Caisse and Glen Fernandes managed this release.

Version 1.79.0

Wed, 13 Apr 2022 14:22:59 +0000

Known Issues

These are patches from library authors which were found too late to be fixed in the release.

Boost.JSON array::erase can segfault, see #692. Patch.

New Libraries

No new libraries.

Updated Libraries

Asio:
- Added bind_allocator.
- Added file_base::sync_all_on_write flag.
- Added missing implementation of basic_file::release().
- Added per-operation cancellation support to signal sets.
- Exposed recycling_allocator as part of the public interface.
- Added the nodiscard attribute to a number of functions.
- Added OpenSSL 3.0 compatibility.
- Added support for adopting an existing SSL* into an ssl::stream<>.
- Enabled executor_work_guard<> in all build configurations.
- Enabled movable socket iostreams when using clang.
- Fixed bind_cancellation_slot and bind_executor compatibility with legacy completion tokens.
- Fixed associator specialisations for experimental::append and experimental::prepend.
- Fixed associated_allocator primary template.
- Fixed io_uring implementations of async_receive_from for sockets and write_some_at for files.
- Fixed io_uring feature detection.
- Fixed experimental::coro's per-operation cancellation.
- Fixed memory management in experimental::promise's type-erased completion handlers.
- Fixed move operator= implementation for ssl::stream.
- Fixed any_io_executor implementation to work when both BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT and BOOST_ASIO_SEPARATE_COMPILATION are defined.
- Fixed implementation of basic_socket::at_mark() when using the sockatmark() system call.
- Changed the recycling allocator to use the default alignment as the minimum alignment for allocations.
- Added a workaround for apparent coroutine codegen bug with Apple's clang.
- On Windows, changed the file support to open files using the same sharing mode as fopen().
- On Linux, fixed UNIX domain sockets implementation to correctly handle EAGAIN.
- Fixed implementation of experimental::basic_channel::reset() and experimental::basic_concurrent_channel::reset().
- Fixed potential undefined behaviour in the experimental::promise.
- Changed the co_spawn implementation to dispatch cancellation signals through the executor in some circumstances.
- Fixed various header inclusion issues.
- Fixed various warnings.
- A number of documentation enhancements, including:
  - Added an overview of Asio's asynchronous model.
  - Reworked reference and requirements documentation in terms of asynchronous model.
  - Updated documentation for dispatch(), post(), and defer().
  - Documented per-operation cancellation for serial ports.
  - Clarified the non-concurrency guarantees made for allocators.
  - Reverted the io_context reference documentation to use executor_work_guard.
  - Added more detailed reference documentation to make_strand(), make_work_guard(), ip::address_v4, ip::address_v6, experimental::basic_channel, and experimental::basic_concurrent_channel.
  - Re-arranged and extended the Overview documentation to cover recently added features.
- Added a C++11 example showing file descriptor passing over local sockets.
- Added C++14 examples of wrapping callback-based APIs in asynchronous operations.
- Consult the Revision History for further details.
Assert:
- source_location().file_name() and source_location().function_name() now return "" instead of "(unknown)".
- Added a source_location constructor from std::source_location.
- Changed BOOST_CURRENT_LOCATION to more closely match the behavior of std::source_location::current(), such as being usable at top level or as a default function argument.
Atomic:
- Fixed compilation for Universal Windows Platform (UWP). (#54)
- Added BOOST_ATOMIC_NO_DARWIN_ULOCK configuration macro. The macro affects compilation on Darwin systems and disables ulock-based implementation of waiting and notifying operations. This may be useful to comply with Apple App Store requirements. (#55)
Beast:
- Added missing include for file_body test.
- Fixed WebSocket handshake response on failure.
- Fixed open append mode for file_posix and file_win32.
- Fixed file open with append/append_existing flag on Windows
- Fixed clang-cl UTF8 path handling for file_win32 and file_stdio.
- Added ARM64 builds to drone CI.
- Fixed async_base documentation link.
- Added tests for file open in append/append_existing mode.
- Updated CI to include gcc 11, clang 12, msvc 14.3.
- Added individual tests to CMake workflow.
- We'd love to know how you or your company use Beast, consider adding an entry to the Companies and Individuals Using Beast list.
- See the full Release Notes for a complete list of changes.
Core:
- Made boost::pointer_traits SFINAE friendly, addressing LWG3545. (Glen Fernandes)
- Added boost::allocator_traits that uses the individual allocator access traits. This implementation supports C++03 and above. (Glen Fernandes)
- Updated the allocator access traits to support most of the C++11 allocator model in C++03. (Glen Fernandes)
- boost/iterator.hpp is deprecated and will be removed in a future release. The header defines boost::iterator template, which is equivalent to std::iterator in <iterator> header. However, since std::iterator is itself deprecated in C++17, users are advised to remove boost::iterator or std::iterator use from their code.
- Added boost::core::verbose_terminate_handler, a utility function intended to be passed to std::set_terminate that prints information about the uncaught exception to stderr.
Describe:
- Enabled unions in BOOST_DESCRIBE_STRUCT and updated examples to check std::is_union<T>.
- Added example of defining a fmtlib class formatter.
- Added example of defining a fmtlib enum formatter.
- Added example of printing pointers to members.
Filesystem:
- v3: path::replace_extension now works in terms of v3 definition of path::extension rather than v4.
- Fixed compilation of path appending and concatenation operators with arguments of types convertible to path or compatible string type. (#223)
- On POSIX systems that support fdopendir and O_NOFOLLOW and on Windows, remove_all is now protected against CVE-2022-21658. The vulnerability is a race condition that allows a third party process to replace a directory that is being concurrently processed by remove_all with a directory symlink and cause remove_all to follow the symlink and remove files in the linked directory instead of removing the symlink itself. (#224)
- On Windows, in remove and remove_all implementation, use POSIX semantics for file removal, when supported by the OS (Windows 10 1709 and later). When POSIX semantics is supported, the file name is removed from the filesystem namespace as soon as the file is marked for deletion, even if it is still open and in use. With legacy Windows semantics, the file name remains present in the the filesystem namespace until the last file handle to the file is closed, which allows the file marked for deletion to be opened and prevents creating new files with the same name. (#216)
- On Windows, remove and remove_all now support deleting read-only directories. Support for removing read-only non-directory files was added previously.
- On Windows, directory_iterator internal implementation has been reworked to better utilize modern Windows APIs, which may improve performance while handling symlinks.
- On Windows, initialize internal WinAPI function pointers early, if possible, to allow Boost.Filesystem operations to be invoked in global constructors. This is only supported on MSVC, GCC, Clang and compatible compilers.
- On Windows, resize_file should no longer fail with an error if the file to be resized is opened.
- Disabled use of the statx syscall on Android prior to 11.0 (API version 30). The syscall is blacklisted by seccomp and causes process termination in runtime. (#229)
- Deprecated: boost/filesystem/string_file.hpp header is deprecated and will be removed in a future release. The header is no longer included by boost/filesystem.hpp by default. Users are advised to implement the functionality themselves or migrate to other implementations.
- Deprecated: Windows CE support is deprecated and will be removed in a future release. Windows CE has been untested for many years and is likely non-functional.
Geometry:
- Major change
  - PR#977 Rescaling is turned off by default. This avoids many related bugs in set operations and buffer.
- Improvements
  - PR#923 Added algorithm closest_points for cartesian point/geometry.
  - PR#939 Added algorithm closest_points for other coordinate systems and geometry combinations excl. boxes.
  - PR#961 Added Web Mercator projection.
  - PR#966 More efficient cartesian distance strategy used in simplify.
- Solved issues
  - #956 Result of simplify algorithm with incorrect closure.
  - #962 Runtime error in R-tree deserialization due to load factor.
  - #971 R-tree insertion time impacted by use of long double on ARM platforms.
- Bugfixes
  - PR#936 Envelope of polygon containing pole.
  - PR#948 Spherical and geographic envelope for near meridian segments.
  - PR#974 Spheroidal normalization utilities for NaN coordinates.
  - Various fixes in set operations and buffer.
Integer:
- Optimized integer_log2 implementation to use bit operations internally. This allows to employ bit instructions available on most modern CPUs. (#31)
IO:
- Added boost::io::basic_nullbuf, a null stream buffer, and boost::basic_onullstream, a null output stream (Glen Fernandes).
Iterator:
- In counting_iterator, added support for built-in 128-bit integer types supported by gcc and clang and compatible compilers on some target platforms.
- Silenced gcc warnings about deprecated implicit copy assignment operator in counting_iterator.
JSON:
- Standalone mode of the library is removed. Users who wish to continue using standalone JSON can switch to the C++ Alliance fork.
- Add std::error_code overloads.
- Add boost::source_location to error_codes.
- Add support for JSON Pointer.
- Naturally grow string during serialization.
LEAF:
- Support for FreeRTOS and other embedded platforms
- Improved diagnostic information
- Improved configuration macros
- BOOST_LEAF_CHECK using statement expressions under __GNUC__
- Fixed symbol demangling bug
Log:
- General changes:
  - In text_file_backend, added support for appending to a previously written log file, when file rotation is used and log file names use file counters.
  - Breaking change: The file_collector interface has changed:
    
    scan_for_files method returns a scan_result structure that contains information collected during the scan;
    
    is_in_storage method added for testing if a path refers to a file within the target storage directory.
  - Added a new invoke_manip stream manipulator that can be used for injecting user's function into a stream output expression.
- Bug fixes:
  - Fixed file counter being set to zero if the user calls text_file_backend::scan_for_files multiple times, and the second and the following calls don't find any new files. (#179)
- See changelog for more details.
Multi-index Containers:
- Improved the efficiency of count operations in ranked indices from O(log(n) + count) to O(log(n)). Contributed by Damian Sawicki.
- Maintenance work.
Nowide:
- Fix compilation issues on some platforms (e.g. GCC 11 on MinGW-w64 and Cygwin)
- Fix missing include when using BOOST_USE_WINDOWS_H and WIN32_LEAN_AND_MEAN
- Add sanity check when using boost::nowide::stat with boost::nowide::stat_t
Optional:
- Fixed issue #98.
- Fixed issue #92.
- Added support for BOOST_NO_IOSTREAM.
- Now aligned storage uses unsigned char rather than char to avoid UB.
- Now using cv-unqualified value_type with placement new to avoid UB.
Predef:
- Version 1.14.0
- Add detection of LoongArch (from Zhang Na).
QVM:
- Added constexpr under C++17
- Improved single header distribution
Smart Pointers:
- Added boost::get_allocator_pointer to obtain the Allocator pointer from the result of boost::allocate_unique (Glen Fernandes).
System:
- Added a boost::source_location parameter to throw_exception_from_error.
- Added throw_exception_from_error overloads for errc::errc_t, std::error_code, std::errc, std::exception_ptr.
- result<T>::value now automatically supplies BOOST_CURRENT_LOCATION to throw_exception_from_error via a default argument.
- Added an errc::make_error_code overload taking a source location.
ThrowException:
- Added boost::throw_with_location, a more lightweight alternative of BOOST_THROW_EXCEPTION for programs that do not use Boost.Exception.
Unordered:
- All containers have been updated to support heterogeneous count, equal_range and find.
- All containers now implement the member function contains.
- erase_if has been implemented for all containers.
- All containers have been updated to support heterogeneous erase and extract.
- Changed behavior of reserve to eagerly allocate.
- Various warning fixes in the test suite.
- Update code to internally use boost::allocator_traits.
- Switch to Fibonacci hashing.
- Update documentation to be written in AsciiDoc instead of QuickBook.
Variant2:
- Added operator<< for monostate.
Wave:
- C++11 now required for building Wave itself
- Fixed bugs:
  - #135: Comma operators in array subscripts are deprecated in C++20
  - #137: Simple unknown directive => found_unknown_directive is not called, stripped of pound.
  - #138: Empty ifdef block does not emit line directive for missing whitespace
  - #143: Parsing __has_include() fails with trailing tokens
  - #145: Sanitizer complains about reset_version()
  - #147: bitwise operations between different enumeration types are deprecated

Updated Tools

Build:
- Includes release of B2 version 4.8.2.

Compilers Tested

Boost's primary test compilers are:

Linux:
- Clang: 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 12.0.0
- Clang, C++11: 3.4, 11.0.0
- Clang, C++14: 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 5.0, 12.0.0
- Clang, C++17: 6.0.1, 7.0.0, 8.0.0, 9.0.0, 10.0.0, 11.0.0, 12.0.0
- Clang, C++20: 11.0.0, 12.0.0, 13.0.0
- GCC: 4.6.3, 11
- GCC, C++11: 4.7.3, 4.8.5, 11
- GCC, C++14: 5.4.0, 6.4.0, 7.3.0, 8.0.1, 9.1.0, 11
- GCC, C++17: 7.3.0, 8.0.1, 9.1.0, 11
- GCC, C++20: 8.0.1, 9.1.0, 10, 11
OS X:
- Apple Clang: 11.0.3
- Apple Clang, C++11: 11.0.3
- Apple Clang, C++14: 11.0.3
- Apple Clang, C++17: 11.0.3
- Apple Clang, C++20: 11.0.3
Windows:
- Visual C++: 10.0, 11.0, 12.0, 14.0, 14.1, 14.2

Acknowledgements

Marshall Clow, Michael Caisse and Glen Fernandes managed this release.