Prior Release (1.56.0)

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What's new in 1.56.0

New libraries

Several new modules and two libraries (Align, Type_Index) were added, covering memory alignment and runtime type information.
Performance improvements

Improved asio I/O backend, single condition variable per io_service, faster select reactor, and optimized hashed_indices and variant::swap.
Dependencies

Added 241 dependencies across 91 libraries and removed 188 dependencies from 78 libraries.
Security & reliability

Numerous bug fixes addressed integer overflows, ABI regressions, race conditions, and platform‑specific crashes.
Developer experience

Added optional::emplace, make_shared/allocate_shared overloads, constexpr support, noexcept specs, and expanded C++11 documentation.

Platform	File	SHA256 Hash
Unix	boost_1_56_0.tar.bz2
Unix	boost_1_56_0.tar.gz
Windows	boost_1_56_0.7z
Windows	boost_1_56_0.zip

Version 1.56.0

August 7th, 2014 16:08 GMT

Documentation

Other Downloads

Windows binaries

Modularization

Boost version control has migrated to a system using git submodules. This shouldn't make too much of a difference to users, although the directory structure is now a bit different.

Parts of some libraries have been moved into different modules, and several new modules have been extracted from existing code. All header paths should remain the same. The new modules are:

Assert: Customizable assert macros. Maintained by Peter Dimov.
Core: Core utilities used by other libraries, with minimal dependencies. Maintained by Peter Dimov, Glen Fernandes and Andrey Semashev.
Lexical_Cast: General literal text conversions, such as an int represented a string, or vice-versa, from Kevlin Henney.
Throw_Exception: A common infrastructure for throwing exceptions from Boost libraries, from Emil Dotchevski.
Winapi: Windows API declarations without <windows.h>, for internal Boost use.

New Libraries

Align:
- Memory alignment functions, allocators, and adaptors, from Glen Fernandes.
Type_Index:
- Runtime/Compile time copyable type info, from Antony Polukhin.

Updated Libraries

Acumulators:
- New accumulators rolling_variance and rolling_moment
Any:
- Fixed rvalue references related issues (#9215, #9462).
- Dropped support of antique compilers.
Asio:
- Fixed asio::spawn() to work correctly with new Boost.Coroutine interface (#9442, #9928).
- Ensured that incomplete asio::spawn() coroutines are correctly unwound when cleaned up by the io_service destructor (#9731).
- Fixed delegation of continuation hook for handlers produced by io_service::wrap() and strand::wrap() (#9741).
- Changed the Windows I/O completion port backend to use ConnectEx, if available, for connection-oriented IP sockets.
- Changed the io_service backend for non-Windows (and non-IOCP Windows) platforms to use a single condition variable per io_service instance. This addresses a potential race condition when run_one() is used from multiple threads.
- Prevented integer overflow when computing timeouts based on some boost::chrono and std::chrono clocks (#9662, #9778).
- Made further changes to EV_CLEAR handling in the kqueue backend, to address other cases where the close() system call may hang on Mac OS X.
- Fixed infinite recursion in implementation of resolver_query_base::flags::operator~ (#9548).
- Made the select reactor more efficient on Windows for large numbers of sockets (#9528).
- Fixed a Windows-specific type-aliasing issue reported by gcc (#9550).
- Prevented execution of compile-time-only buffer test to avoid triggering an address sanitiser warning (#8295).
- Disabled the GetQueuedCompletionStatus timeout workaround on recent versions of Windows.
- Added support for string-based scope IDs when using link-local multicast addresses.
- Changed IPv6 multicast group join to use the address's scope ID as the interface, if an interface is not explicitly specified.
- Fixed multicast test failure on Mac OS X and the BSDs by using a link-local multicast address.
- Worked around a gcc problem to do with anonymous enums (#10042).
- Reverted the Windows HANDLE backend change to ignore ERROR_MORE_DATA. Instead, the error will be propagated as with any other (i.e. in an error_code or thrown as a system_error), and the number of bytes transferred will be returned. For code that needs to handle partial messages, the error_code overload should be used (#10034).
- Fixed an off-by-one error in the signal_set implementation's signal number check (#9324).
- Changed to use SSE2 intrinsics rather than inline assembly, to allow the Cray compiler to work.
- Stopped using certain Winsock functions that are marked as deprecated in the latest Visual C++ and Windows SDK.
- Added a workaround for building the unit tests with gcc on AIX.
- Various minor documentation improvements (#8295, #9605, #9771).
Assign:
- Resolve some C++11 ambiguities (#3073).
Atomic:
- The library has been redesigned. Besides internal refactoring, various bugs were fixed, including incorrect values of feature test macros and integer overflow handling.
- Changed values of the memory_order enumeration. The concrete values are not part of the interface, but this change may potentially break ABI, if the enum is used in user's interfaces.
- Implemented support for 128-bit atomic operations on Windows x64 with MSVC. The library assumes presence of the cmpxchg16b instruction in the target CPUs. Some early AMD CPUs don't support this instruction. To target those define the BOOST_ATOMIC_NO_CMPXCHG16B macro.
- Implemented experimental support for Windows ARM target with MSVC.
- Implemented experimental support for DEC Alpha target with GCC.
- Improved support for ARMv6 and later with GCC. Implemented all atomic operations as assembler blocks instead of CAS-based loops. 64-bit operations are supported with ARMv7.
- Implemented optional support for the BOOST_ATOMIC_FLAG_INIT macro and static initialization of atomic_flag. (#8158)
- Fixed compilation for SPARCv9 target. (#9446)
- Fixed compilation for PowerPC target. (#9447)
- Fixed several compatibility problems with Clang on x86 and x86-64. (#9610, #9842)
- Removed specialized code for Windows on IA64 platform.
Circular Buffer:
- #9970,#9334 Support for the C++11 allocator model.
- Dropped support of antique compilers.
Concept Check:
- Fewer warnings (includes #5012).
Container:
- Added DlMalloc-based Extended Allocators.
- Improved configurability of tree-based ordered associative containers. AVL, Scapegoat and Splay trees are now available to implement set, multiset, map and multimap.
- Fixed bugs:
Context:
- fcontext_t is opaque pointer to context-data
- changed signature of make_fcontext()
- #8826 no executable stack
- #9437 catch exceptions on iOS and Windows Phone 8
- #9445 support for x32 ABIs
- #9522 support for powerpc_64le
- #9743 bugfix for powerpc_64 le/be
- #9774 bugfix for x86 on Mac OS X + clang
Coroutine:
- support of symmetric coroutines
- #9355 fix race condition in protected_stack_allocator
- #9551 list of supported architectures
- #9734 wrong check of mmap() return value
- #9735 no memset() for protected_stack_allocator
- #9760 coroutine iterator need const operator==
- #10070 mmap() return value
- #10157 file descriptor not required in protected_stack_allocator
Dynamic Bitset:
- Support for C++11 move constructors
- Warning fixes on MSVC 2013
- Support for C++11 minimal allocators
- Add noexcept specifications
Chrono:
- #6918 Boost Chrono compilation failure on HP uX due to undefined pthread_getcpuclockid
- #8006 Boost::Chrono Assertion at startup - steady_clock::now() - Windows
- #9337 chrono::process_cpu_clock time points wrong by factor 1000 on Linux
- #9342 Regression on process_cpu_clock::timepoint io on V2
- #9419 boost::chrono::floor()/round() and negative durations is wrong
- #9698 boost::chrono::thread_clock not declared in OSX
- #9720 boost::this_thread::sleep_for() sometimes returns immediately on win32
- #9859 Remove references to gcc-mingw
- #9918 chrono compilation error on Solaris, funciton timegm
- #9811 boost/boost/chrono/duration.hpp:355:56: error: call to non-constexpr function 'static std::numeric_limits<float>::_Ty std::numeric_limits<float>::max()' /home/zosun/input_service/inputservices-core-service/other/boost/boost/chrono/duration.hpp: In static member function 'static constexpr double boost::chrono::detail::chrono_numeric_limits<double, true>::lowest()':
- #10069 Overflow in chrono clocks on 32bit
- #10151 timegm function not available on QNX
Flyweight:
- In compilers with variadic template support, boost::flyweight<T> now provides a perfectly forwarding constructor to T::T (previously an emulation was used).
- flyweight now replicates the initializer-list constructors and assignment operators of its underlying type.
- Fixed intermodule static initialization problem (ticket #9553).
- Maintenance fixes.
Fusion:
- Fusion is enabled for use on GPU
Geometry:
- Additional functionality
  - New algorithm buffer for inflating/deflating geometries (buffer itself already existed but that was only to enlarge a box)
  - New algorithm remove_spikes, algorithm to remove spikes from a ring, polygon or multi_polygon.
  - New algorithm point_on_surface, generating a point lying on the surface (interior) of the polygon
  - New algorithm is_simple, returning true if a geometry is simple according to the OGC standard
  - New algorithm is_valid, returning true if a geometry is valid according to the OGC standard
  - New algorithm crosses for checking this spatial relation according to the OGC standard
  - The set operation algorithms (difference, intersection, sym_difference and union_) now support as input pairs of pointlike or linear geometries
  - The distance and comparable_distance algorithms now support all pairs of geometry combinations
  - The spatial relations which didn't support it (covered_by, touches, within, etc.) now support as input linear and/or areal geometries
  - The support for boost::variants as input geometries in various algorithms
  - The rtree support for indexing segments
  - The rtree nearest() predicate support for arbitrary geometries
- Solved tickets
  - 8310 Wrong results with overlapping polygons (fixed using point_on_surface for disjoint)
  - 8375 sym_difference of non-closed polygons returns closed polygon
  - 8376 difference of non-closed polygons returns closed polygon
  - 9081 Booleans create self-intersecting polygons from non-self-intersecting polygons
  - 9245 Check for process errors in make_qbk.py
  - 9563 (Sym)difference not successful, fixed by rescaling to robust type
  - 9628 Wrong result of within() due to the winding strategy not working correctly for nearly-horizontal segments
  - 9871 Remove spike in polygon with only a spike
  - 9947 Missing info about WKT in documentation
  - 9759 Invalid results of R-tree knn queries for non-cartesian coordinate systems
  - 10019 Difference of Linestring and Box returns their intersection
  - 10077 Wrong types in concept checks in boost/geometry/arithmetic/arithmetic.hpp
- Bug fixes
  - intersects(polygon) could return a self-intersection-point for its closing point, fixed
  - equals() could return invalid results for non-simple linear geometries according to the OGC standard, fixed
  - touches() didn't work properly for CCW areal geomtries, fixed
  - rtree nearest queries returned wrong elements for non-cartesian coordinate systems, fixed
  - rtree crashed in some cases when used with Interprocess allocator, fixed
Hash:
- Removed some Visual C++ 6 workarounds.
- Ongoing work on improving hash_combine, this changes the previously documented algorithm for the function.
Interprocess:
- Fixed bugs:
- ABI breaking: #9221 showed that BOOST_INTERPROCESS_MSG_QUEUE_CIRCULAR_INDEX option of message queue, was completely broken so an ABI break was necessary to have a working implementation.
- Simplified, refactored and unified (timed_)lock code based on try_lock(). There were several bugs when handling timeout expirations.
- Changed the implementation of condition variables' destructors to allow POSIX semantics (the condition variable can be destroyed after all waiting threads have been woken up)..
- Added BOOST_INTERPROCESS_SHARED_DIR_PATH option to define the shared directory used to place shared memory objects when implemented as memory mapped files.
- Added support for BOOST_USE_WINDOWS_H. When this macro is defined Interprocess does not declare used Windows API function and types, includes all needed windows SDK headers and uses types and functions declared by the Windows SDK.
- Added get_size to windows_shared_memory.
Intrusive:
- Improved Doxygen generated reference and updated and fixed forward-declaration header.
- ABI breaking: Fixed ABI regression introduced in Boost 1.55 version, mainly noticeable on MSVC compilers.
- Source breaking: Removed previously deprecated xxx_dont_splay functions from splay containers, splay_set_base_hook and splay_set_member_hookfrom splay containers and bool splay = true extra parameter in splaytree_algorithms functions.
- Fixed bugs:
- Optimized tree rebalancing code to avoid redundant assignments.
- Added 64 bit prime values for suggested_upper_bucket_count/suggested_lower_bucket_count in 64 bit platforms.
- Deleted workarounds for old SUN_CC compilers, those are now unsupported as modern SunPro compilers are standard-corforming enough.
Lexical Cast:
- Added the try_lexical_convert function, that retuns false in case of failed conversion and does not require output parameter to be Default Constructable (#6700).
- Fixed conversion of string values with leading zeroes to bool (#9659).
- Code was changed to produce a smaller binaries and simplify compiler's work (#9046).
- Boost.LexicalCast library was separated from the Boost.Conversion library.
- Fixed some warnings (#8991).
Log:
- General changes:
  - For Windows targets, the library now compiles for Windows XP by default.
  - Added indexing operators with attribute_name arguments to record and record_view.
  - Added operators for non-const object output to basic_formatting_ostream. (#9389)
  - Added support for putting function names and source file names of named scopes into the formatted strings. (#9263)
  - Added support for incomplete and empty markers to the named scope formatter. (#9123)
  - The default presentation for incomplete named scope lists has changed: trailing scope delimiter is omitted.
  - Added a support header for std::regex.
  - By default Boost.Log uses Boost.Regex internally as the regular expressions backend. The backend can be changed by defining configuration macros.
- Bug fixes:
  - Fixed dump manipulator output on AVX2-enabled CPUs (e.g. Intel Haswell).
  - Fixed compilation of get_attribute method of loggers.
  - Fixed a possible race in locked_backend() function implementation of synchronous and asynchronous sink frontends.
  - Fixed a possible infinite block of the logging threads in the asynchronous sink enqueue methods when block_on_overflow strategy was used.
- See changelog for more details.
Math:
- Breaking change: moved a number of non-core headers that are predominantly used for internal maintenance into libs/math/include_private. The headers effected are boost/math/tools/test_data.hpp, boost/math/tools/remez.hpp, boost/math/constants/generate.hpp, boost/math/tools/solve.hpp, boost/math/tools/test.hpp. You can continue to use these headers by adding libs/math/include_private to your compiler's include path.
- Breaking change: A number of distributions and special functions were returning the maximum finite value rather than raising an overflow_error, this has now been fixed, which means these functions now behave as documented. However, since the default behavior on raising an overflow_error is to throw a std::overflow_error exception, applications which have come to reply rely on these functions not throwing may experience exceptions where they did not before. The special functions involved are gamma_p_inva, gamma_q_inva, ibeta_inva, ibetac_inva, ibeta_invb, ibetac_invb, gamma_p_inv, gamma_q_inv. The distributions involved are pareto_distrib, beta_distrib, geometric_distrib, negative_binomial_distrib, binomial_distrib, chi_squared_distrib, gamma_distrib, inverse_chi_squared_distrib, inverse_gamma_distrib. See #10111.
- Fix round and trunc functions so they can be used with integer arguments, see #10066.
- Fix Halley iteration to handle zero derivative (with non-zero second derivative), see #10046.
- Fix Geometric distribution use of Policies, see #9833.
- Fix corner cases in the negative binomial distribution, see #9834.
- Fix compilation failures on Mac OS.
- Added bernoulli_numbers, changed arbitrary precision tgamma/lgamma to use Sterling's approximation (from Nikhar Agrawal).
- Added first derivatives of the Bessel functions: cyl_bessel_j_prime, cyl_neumann_prime, cyl_bessel_i_prime, cyl_bessel_k_prime, sph_bessel_prime and sph_neumann_prime (from Anton Bikineev).
- Fixed buggy Student's t example code, along with docs for testing sample means for equivalence.
- Documented max_iter parameter in root finding code better, see #9225.
- Add option to explicitly enable/disable use of __float128 in constants code, see #9240.
- Cleaned up handling of negative values in Bessel I0 and I1 code (removed dead code), see #9512.
- Fixed handling of very small values passed to tgamma and lgamma so they don't generate spurious overflows (thanks to Rocco Romeo).
- #9672 PDF and CDF of a Laplace distribution throwing domain_error Random variate can now be infinite.
- Fixed several corner cases in rising_factorial, falling_factorial and tgamma_delta_ratio with thanks to Rocco Romeo.
- Removed constant pow23_four_minus_pi whose value did not match the name (and was unused by Boost.Math), see #9712.
Move:
- Added BOOST_MOVE_RET.
- Fixed bug #9482: "MSVC macros not undefined in boost/move/detail/config_end.hpp", #9045: "Wrong macro name on docs", #8420: "move's is_convertible does not compile with aligned data".
MPL:
- boost::mpl::for_each is enabled for use on GPU
MultiArray:
- #5664 operator() checks for Collection concept but requires RandomAccessCollection
- #4874 compile errors using Visual C++ 2010 in debug mode
- #3581 MultiArray storage order example incorrect for fortran_storage_ordering
- #4032 Move MultiArray concepts out of detail namespace
- #9212 Broken links to C++ standard papers
- #8368 GCC -Wundef warning about BOOST_MULTI_ARRAY_NO_GENERATORS in multi_array
Multi-index Containers:
- The erase(iterator) member function of hashed indices used to have poor performance under low load conditions due to the requirement that an iterator to the next element must be returned (see ticket #4264). In accordance with the resolution of LWG issue #579, this problem has been fixed while maintaining the interface of erase, at the expense of using one more word of memory per element. In fact, C++ complexity requirements on unordered associative containers have been improved for hashed indices so that
  - deletion of a given element is unconditionally constant-time,
  - worst-case performance is not O(n) but O(n_dist), where n_dist is the number of non-equivalent elements in the index.
  Due to the fact that hashed indices rely on a new data structure, the internal representation of their iterators and local iterators have changed, which affects serialization: their corresponding serialization class version has been bumped from 0 to 1. Old archives involving hashed index (local) iterators can be loaded by Boost 1.56 version of Boost.MultiIndex, but not the other way around.
- Hashed indices now provide reserve.
- Hashed indices can now be checked for equality and inequality following the (suitably adapted) C++ standard specification in [unord.req].
- The public interface of Boost.MultiIndex provide noexcept specifications where appropriate (for compliant compilers).
- Improved performance of failed insertions into a multi_index_container.
- Much internal code aimed at supporting MSVC++ 7.0 and prior has been removed. Compilation times without this legacy code might be slightly faster.
- Fixed a bug with insertion via iterators dereferencing to rvalues (ticket #9665).
- Made Boost.MultiIndex compatible with BOOST_BIND_NO_PLACEHOLDERS (ticket #9798).
- Maintenance fixes.
Multiprecision:
- Change floating point to rational conversions to be implicit, see 10082.
- Fix definition of checked_cpp_rational typedef.
- Fix bug in assignment from string in cpp_int, see 9936.
- Added new cpp_bin_float backend for binary floating point.
- Fix bug in assignment from string in cpp_int, see 9936.
- Added MSVC-specific #include for compiler intrinsics, see 9336.
- Fixed various typos in docs, see 9432.
- Fixed gmp_rational to allow move-copy from an already copied-from object, see 9497.
- Added list of values for numeric_limits.
Odeint:
- Added algebra and operations dispatcher for automatic detection of appropriate algebras and operations.
- Added support for Eigen, Boost.Multiarray, Boost.Mpi, Boost.Compute, Blaze, and NT2.
- Changed algebra interface to use algebra.norm_inf function.
- Added iterators for iterating through the solution of the ODEs, hence an alternative to the integrate functions.
- Added the Velocity-Verlet method.
- Minor bug fixes.
Optional:
- Added support for rvalue references. Now optional<T> works with moveable but non-copyable T's.
- Improved swap (now uses move operations).
- Added function emplace(). This is the last of the requests from #1841.
- optional is moveable, including conditional noexcept specifications, which make it move_if_noexcept-friendly.
- Using explicit operator bool() on platforms that support it (#4227) (breaking change).
- Forward declaration of operator<<(ostream&, optional const&) to prevent inadvertent incorrect serialization of optional objects.
- Removed depprecated function reset() from examples (#9005).
- Equality comparison with boost::none does not require that T be EqualityComparable.
- Optional rvalue references are explicitly disallowed.
- Binding temporaries to optional references is explicitly disallowed (breaking change).
- More ways to access the contained value, functions value(), value_or(), value_or_eval().
- Updated and reorganized documentation, added tutorial and quick guide sections.
Predef:
- Addition of BOOST_PLAT_* platform definitions for MinGW and Windows platform variants.
- Detection of ARM architecture for Windows compilers to target mobile devices of Windows 8.
- Improved ARM detection for 64 bit ARM.
- Added detection of iOS as an operating system.
- Improved detection of endianess on some platforms.
- Addition of exclusive plus emulated definitions for platform and compiler detection.
Preprocessor:
- When using variadic macros tuple functionality was added to match all the array functionality.
Program Options:
- Columns in the --help output are now aligned across all option groups (#6114).
- Option names with dashes are no longer truncated in error messages (#8009).
Regex:
- Breaking change: corrected behavior of basic_regex<>::mark_count() to match existing documentation, basic_regex<>::subexpression(n) changed to match, see #9227
- Fixed issue #8903.
- Fixed documentation typos from #9283.
- Fixed bug in collation code that failed if the locale generated collation strings with embedded nul's, see #9451.
- Apply patch for unusual thread usage (no statically initiallized mutexes), see #9461.
- Added better checks for invalid UTF-8 sequences, see #9473.
Smart Pointers:
- Updated the overloads of make_shared and allocate_shared of array types (T[] or T[N]) to conform to the specification in C++ standard paper N3939 and significantly reduced the spatial overhead of the internal bookkeeping structures.
- Updated the implementations of make_shared and allocate_shared for scalar types and array types, respectively, to resolve C++ standard library defect report #2070.
Thread:
- New Experimental Features:
  - #7446 Async: Add when_any.
  - #7447 Async: Add when_all.
  - #7448 Async: Add async taking a scheduler parameter.
  - #8274 Synchro: Add concurrent queue
  - #8513 Async: Add a basic thread_pool executor.
  - #8518 Synchro: Add a latch class.
  - #8516 Async: Add future/shared_future::then taking a scheduler as parameter.
  - #9058 with_lock_guard function
  - #9571 Add a dynamic executor and an executor adaptor
- Fixed Bugs:
  - #8070 prefer GetTickCount64 over GetTickCount
  - #9333 ex_scoped_thread compile fails on msvc-12.0
  - #9341 compile error scoped_thread(move semantics) intel-linux-14.0.1
  - #9366 async(Executor, ...) fails to compile with msvc-10,11,12
  - #9402 test_excutor regression on msvc-10,11,12
  - #9404 ex_make_future regression error
  - #9471 Synchronization documentation nits
  - #9535 Missing exception safety might result in crash
  - #9618 try_join_for problem: program is not terminate.
  - #9625 Please rewrite boost::thread::~thread() reference section
  - #9632 public method start_thread in boost::thread class
  - #9673 thread compilation with MingW/gcc on Windows gives errors
  - #9708 boost::condition_variable::timed_wait unexpectedly wakes up while should wait infinite
  - #9711 future continuation called twice
  - #9867 Remove references to gcc-mingw
  - #10008 Boost Synchronization documentation typos (futures)
  - #10058 Null pointer access in once
  - #10125 call_once: compile errors in variadic version with rvalue reference emulation
  - #10126 call_once: deprecate (Function, once_flag&) overload
  - #10147 pthread_delay_np() parameters different on AIX even with gcc
  - #10155 thread::physical_concurrency() always returns 0 on PowerPC
  - #10184 Future: multiply defined symbols
TR1:
- This library is now deprecated.
TTI:
- Ticket #9441: Added better support for Sun Solaris Studio C++ compiler.
- Ticket #9444: Handle all situations where the enclosing class is not a class type.
Unordered:
- Minor documentation and warning fixes (#9377, #9719).
- Always use prime number of buckets for integers. Fixes performance regression when inserting consecutive integers (#9282).
- Only construct elements using allocators, as specified in C++11 standard.
Utility:
- Some components were moved to the new Boost.Core library.
- empty_deleter is deprecated in favor of null_deleter from Boost.Core. empty_deleter is an alias for null_deleter, it will be removed in future releases.
- base_from_member utility now supports lvalue reference member types. (#7577)
UUID:
- Added basic support for C++11 features.
- Implemented SSE-optimized versions of some functions of uuid, including comparison operators and swap. The support for different versions of SSE is automatically detected at compile time for most compilers, but can also be explicitly enabled or disabled with configuration macros. (#8509)
- Silenced some compiler warnings. (#8495, #8697)
Variant:
- Breaking change: Variant now uses variadic templates if they are supported by compiler. This leads to smaller binaries and better compilation times but in some cases may break metaprogramming functions, especially if BOOST_VARIANT_ENUM_PARAMS and BOOST_VARIANT_ENUM_SHIFTED_PARAMS are not used. Usage of variadic templates may be disabled.
- Added polymorphic_get function #9479.
- Move-only classes now can be returned by visitors.
- Optimized variant::swap() and fixed ambiguity in move_swap #2839.
- Added conditional noexcepts to move assignments, default and move constructors making boost::variant move_if_noexcept-friendly (#7911).
- Exceptions are now visible across modules even with -fvisibility=hidden flags.
- Dropped support of antique compilers.
- Fixed some warnings (#3020).

Compilers Tested

Boost's primary test compilers are:

Linux:
- Clang: 3.4, 3.3, 3.2, 3.1, 3.0
- Clang, C++98: 3.3.16
- Clang, C++11, libc++: 3.4.2
- Clang, C++1y: 3.3.16
- GCC: 4.8.2, 4.8.1, 4.7.3, 4.6.4, 4.4.7
- GCC, C++98: 4.9.0
- GCC, C++11: 4.8.2
- GCC, C++1y: 4.9.0
- Intel: 13.1
OS X:
- Apple Clang: 5.1
- Apple Clang, C++11: 5.1
- GCC: 4.2.1
- Intel: 12.0
Windows:
- GCC, mingw: 4.9.0, 4.8.2, 4.7.3, 4.7.2, 4.6.3, 4.5.4, 4.4.7
- Visual C++: 12.0, 11.0, 10.0, 9.0
FreeBSD:
- GCC: 4.2.1
QNX:
- QCC: 4.4.2

Boost's additional test compilers include:

Linux:
- Clang: 3.4, 3.3, 3.2, 3.1, 3.0
- Clang, C++98: 3.3.16
- Clang, C++11, libc++: 3.4.2
- Clang, C++1y: 3.3.16
- Clang, C++14, libc++: trunk
- GCC: 4.8.2, 4.8.1, 4.7.3, 4.6.4, 4.4.7
- GCC, C++98: 4.9.0
- GCC, C++11: 4.9.0, 4.8.2
- GCC, C++1y: 4.9.0
- Intel: 13.1, 13.0, 12.1, 11.1
OS X:
- Apple Clang: 5.1
- Apple Clang, C++11:
- Clang: trunk
- Clang, C++11: trunk
- GCC: 4.2.1
- Intel: 12.0
Windows:
- GCC, mingw: 4.9.0, 4.8.2, 4.7.2, 4.6.3, 4.5.4, 4.4.7
- Visual C++: 12.0, 11.0, 10.0, 9.0
FreeBSD:
- GCC: 4.2.1
QNX:
- QCC, ARM: 4.4.2
- QCC, x86: 4.4.2

Acknowledgements

Beman Dawes, Eric Niebler, Rene Rivera, Daniel James, Vladimir Prus and Marshall Clow managed this release.

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Prior Release (1.56.0)

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