• LibstdcxxTodo

This page lists open projects (some big, some small) for libstdc++, the GNU implementation of the C++ Standard Library.

The GettingStarted page has information for people who want to start contributing to GCC.

This page is incomplete -- it may not list changes from the most recent meetings, and only lists changes since the Nov 2015 meeting, but there are some issues from previous meetings that we haven't implemented yet

QoI matters

• Add noexcept to tuple constructors

  • as proposed by Scott's 2017-02-26 proposed resolution for 2899.

• More Doxygen documentation in the code (and maybe switch to using markdown for formatting within comments?)

Unimplemented changes

Changes from Kona Feb 2019

• 3012 atomic<T> is unimplementable for non-is_trivially_copy_constructible T

• 3040 basic_string_view::starts_with Effects are incorrect

• 3077 (push|emplace)_back should invalidate the end iterator

  • No changes required

• 3087 One final &x in §[list.ops]

• 3101 span's Container constructors need another constraint

• 3112 system_error and filesystem_error constructors taking a string may not be able to meet their postconditions

• 3119 Program-definedness of closure types

• 3133 Modernizing numeric type requirements

  • No changes needed

• 3144 span does not have a const_pointer typedef

• 3173 Enable CTAD for ref-view

• 3179 subrange should always model Range

• 3180 Inconsistently named return type for ranges::minmax_element

• 3182 Specification of Same could be clearer

• P0339R6 polymorphic_allocator<> as a vocabulary type

• P0340R3 Making std::underlying_type SFINAE-friendly

• P0738R2 I Stream, You Stream, We All Stream for istream_iterator

• P1458R1 Mandating the Standard Library: Clause 16 - Language support library

  • No changes needed

• P1459R1 Mandating the Standard Library: Clause 18 - Diagnostics library

  • No changes needed

• P1462R1 Mandating the Standard Library: Clause 20 - Strings library

  • No changes needed

• P1463R1 Mandating the Standard Library: Clause 21 - Containers library

  • Must enforce is_same_v<allocator_type::value_type, value_type> in C++20 mode

• P1464R1 Mandating the Standard Library: Clause 22 - Iterators library

  • Need to constrain operators for reverse_iterator and move_iterator

• P1164R1 Make create_directory() Intuitive

• P1001R2 Target Vectorization Policies from Parallelism V2 TS to C++20

• P1227R2 Signed ssize() functions, unsigned size() functions

• P1252R2 Ranges Design Cleanup

• P1024R3 Usability Enhancements for std::span

• P0920R2 Precalculated hash values in lookup

• P1357R1 Traits for [Un]bounded Arrays

• P0052R10 Generic Scope Guard and RAII Wrapper for the Standard Library (Library Fundamentals)

Changes from San Diego Nov 2018

• 2960 [fund.ts.v3] nonesuch is insufficiently useless

• P1210R0 Completing the Rebase of Library Fundamentals, Version 3, Working Draft

• 2183. Muddled allocator requirements for match_results constructors

  • No changes required

• 2184. Muddled allocator requirements for match_results assignments

  • No changes required

• 2412. promise::set_value() and promise::get_future() should not race

• 2682. filesystem::copy() won't create a symlink to a directory

• 2936. Path comparison is defined in terms of the generic format

• 2943. Problematic specification of the wide version of basic_filebuf::open

• 2995. basic_stringbuf default constructor forbids it from using SSO capacity

  • https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80676

• 2996. Missing rvalue overloads for shared_ptr operations

• 3008. make_shared (sub)object destruction semantics are not specified

• 3025. Map-like container deduction guides should use pair<Key, T>, not pair<const Key, T>

• 3031. Algorithms and predicates with non-const reference arguments

• 3037. polymorphic_allocator and incomplete types

  • No changes required

• 3038. polymorphic_allocator::allocate should not allow integer overflow to create vulnerabilities

• 3054. uninitialized_copy appears to not be able to meet its exception-safety guarantee

• 3065. LWG 2989 missed that all path's other operators should be hidden friends as well

• 3096. path::lexically_relative is confused by trailing slashes

• 3116. OUTERMOST_ALLOC_TRAITS needs remove_reference_t

• 3122. __cpp_lib_chrono_udls was accidentally dropped

• 3127. basic_osyncstream::rdbuf needs a const_cast

• 3128. strstream::rdbuf needs a const_cast

  • No changes required

• 3129. regex_token_iterator constructor uses wrong pointer arithmetic

• 3130. §[input.output] needs many addressof

• 3131. addressof all the things

• 3132. Library needs to ban macros named expects or ensures

  • No changes required

• 3137. Header for __cpp_lib_to_chars

• 3140. COMMON_REF is unimplementable as specified

• 3145. file_clock breaks ABI for C++17 implementations

• 3147. Definitions of "likely" and "unlikely" are likely to cause problems

  • No changes needed

• 3148. <concepts> should be freestanding

• 3153. Common and common_type have too little in common

• 3154. Common and CommonReference have a common defect

• 3160. atomic_ref() = delete; should be deleted

• P1123R0 Editorial Guidance for merging P0019r8 and P0528r3

  • Nothing to do

• P0487R1 Fixing operator>>(basic_istream&, CharT*) (LWG 2499)

• P0602R4 variant and optional should propagate copy/move triviality

• P0655R1 visit<R>: Explicit Return Type for visit

• P0972R0 <chrono> zero(), min(), and max() should be noexcept

• P1006R1 Constexpr in std::pointer_traits

• P1032R1 Misc constexpr bits

• P1148R0 Cleaning up Clause 20

  • [char.traits] p3 now says "If X::char_type is not the same type as C, the program is ill-formed." Need to enforce that in basic_string and iostreams.

• P0318R1 unwrap_ref_decay and unwrap_reference

• P0357R3 reference_wrapper for incomplete types

• P0608R3 A sane variant converting constructor

• P0771R1 std::function move constructor should be noexcept

• P1007R3 std::assume_aligned

• P1020R1 Smart pointer creation with default initialization

• P1285R0 Improving Completeness Requirements for Type Traits

• P1248R1 Remove CommonReference requirement from StrictWeakOrdering (a.k.a Fixing Relations)

• P0591R4 Utility functions to implement uses-allocator construction

• P0899R1 LWG 3016 is Not a Defect

• P1085R2 Should Span be Regular?

• P1165R1 Make stateful allocator propagation more consistent for operator+(basic_string)

• P0896R4 The One Ranges Proposal

  • HUGE, consider using cmcstl2 implementation

• P0356R5 Simplified partial function application

• P0919R3 Heterogeneous lookup for unordered containers

• P1209R0 Adopt Consistent Container Erasure from Library Fundamentals 2 for C++20

Changes from Rapperswil Jun 2018

(some of these are done, but this list needs to be updated)

• 2139 What is a user-defined type?

  • No changes required

• 2970 Return type of std::visit misspecified

• 3058 Parallel adjacent_difference shouldn't require creating temporaries

• 3062 Unnecessary decay_t in is_execution_policy_v should be remove_cvref_t

  • reported upstream as https://bugs.llvm.org/show_bug.cgi?id=41591

• 3067 recursive_directory_iterator::pop must invalidate

• 3074 Non-member functions for valarray should only deduce from the valarray

• 3076 basic_string CTAD ambiguity

• 3079 LWG 2935 forgot to fix the existing_p overloads of create_directory

• 3080 Floating point from_chars pattern specification breaks round-tripping

• 3083 What should ios::iword(-1) do?

• 3094 §[time.duration.io]p4 makes surprising claims about encoding

• 3100 Unnecessary and confusing "empty span" wording

• 3102 Clarify span iterator and const_iterator behavior

• 3104 Fixing duration division

• P0475R1 LWG 2511: guaranteed copy elision for piecewise construction

• P0476R2 Bit-casting object representations

• P0788R3 Standard Library Specification in a Concepts and Contracts World

• P0458R2 Checking for Existence of an Element in Associative Containers

• P0759R1 fpos Requirements

  • Nothing to do?

• P1023R0 constexpr comparison operators for std::array

• P0769R2 Add shift to <algorithm>

• P0887R1 The identity metafunction

• P0879R0 Constexpr for swap and swap related functions

• P0758R1 Implicit conversion traits and utility functions

• P0556R3 Integral power-of-2 operations

• P0019R8 Atomic Ref

• P0935R0 Eradicating unnecessarily explicit default constructors from the standard library

• P0646R1 Improving the Return Value of Erase-Like Algorithms

• P0619R4 Reviewing Deprecated Facilities of C++17 for C++20

• P0898R3 Standard Library Concepts

Changes from Jacksonville Feb 2018

(some of these are done, but this list needs to be updated)

• 2164 What are the semantics of vector.emplace(vector.begin(), vector.back())?

• 2243 istream::putback problem

• 2816 resize_file has impossible postcondition

• 2843 Unclear behavior of std::pmr::memory_resource::do_allocate()

• 2849 Why does !is_regular_file(from) cause copy_file to report a "file already exists" error?

• 2851 std::filesystem enum classes are now underspecified

• 2969 polymorphic_allocator::construct() shouldn't pass resource()

• 2975 Missing case for pair construction in scoped and polymorphic allocators

• 2989 path's stream insertion operator lets you insert everything under the sun

• 3000 monotonic_memory_resource::do_is_equal uses dynamic_cast unnecessarily

• 3004 §[string.capacity] and §[vector.capacity] should specify time complexity for capacity()

• 3005 Destruction order of arrays by make_shared/allocate_shared only recommended?

• 3007 allocate_shared should rebind allocator to cv-unqualified value_type for construction

• 3009 Including <string_view> doesn't provide std::size/empty/data

• 3013 (recursive_)directory_iterator construction and traversal should not be noexcept

• 3014 More noexcept issues with filesystem operations

• 3015 copy_options::unspecified underspecified

• -((3017 list splice functions should use addressof)--

• 3026 filesystem::weakly_canonical still defined in terms of canonical(p, base)

• 3030 Who shall meet the requirements of try_lock?

• 3034 P0767R1 breaks previously-standard-layout types

• 3035 std::allocator's constructors should be constexpr

  • No changes required

• 3039 Unnecessary decay in thread and packaged_task

• 3041 Unnecessary decay in reference_wrapper

• 3042 is_literal_type_v should be inline

  • No changes required

• 3043 Bogus postcondition for filesystem_error constructor

• 3045 atomic<floating-point> doesn't have value_type or difference_type

• 3048 transform_reduce(exec, first1, last1, first2, init) discards execution policy

• 3051 Floating point classifications were inadvertently changed in P0175

• 2946 LWG 2758's resolution missed further corrections

• 3075 basic_string needs deduction guides from basic_string_view

• P0754R2 <version>

• P0809R0 Comparing Unordered Containers (resolves LWG#2831)

• P0355R7 Extending chrono to Calendars and Time Zones

• P0966R1 string::reserve Should Not Shrink

• P0551R3 Thou Shalt Not Specialize std Function Templates!

• P0753R2 Manipulators for C++ Synchronized Buffered Ostream

• P0122R7 <span>

• P0858R0 Constexpr iterator requirements

Changes from Albuquerque Nov 2017

(some of these are done, but this list needs to be updated)

• 2950 std::byte operations are misspecified

• 2952 iterator_traits should work for pointers to cv T

• 2953 LWG 2853 should apply to deque::erase too

• 2964 Apparently redundant requirement for dynamic_pointer_cast

• 2965 Non-existing path::native_string() in filesystem_error::what() specification

• 2972 What is is_trivially_destructible_v<int>?

  • No changes required

• 2976 Dangling uses_allocator specialization for packaged_task

• 2977 unordered_meow::merge() has incorrect Throws: clause

• 2978 Hash support for pmr::string and friends

• 2979 aligned_union should require complete object types

• 2980 Cannot compare_exchange empty pointers

• 2981 Remove redundant deduction guides from standard library

• 2982 Making size_type consistent in associative container deduction guides

• 2988 Clause 32 cleanup missed one typename

• 2993 reference_wrapper<T> conversion from T&&

• 2998 Requirements on function objects passed to {forward_,}list-specific algorithms

• 3001 weak_ptr::element_type needs remove_extent_t

• 3024 variant's copies must be deleted instead of disabled via SFINAE

• 2958 Moves improperly defined as deleted

  • No changes required

• P0550R2 Transformation Trait remove_cvref

• P0777R1 Treating Unnecessary decay

• P0600R1 nodiscard in the Library

• P0439R0 Make std::memory_order a scoped enumeration

• P0053R7 C++ Synchronized Buffered Ostream

• P0653R2 Utility to convert a pointer to a raw pointer

• P0202R3 Add constexpr modifiers to functions in <algorithm> and <utility> Headers

• P0415R1 Constexpr for std::complex

• P0718R2 Atomic shared_ptr

• P0020R6 Floating Point Atomic

• P0616R0 de-pessimize legacy <numeric> algorithms with std::move

• P0457R2 String Prefix and Suffix Checking

Changes from Toronto July 2017

• 2901 Variants cannot properly support allocators

  • No changes required

• 2956 filesystem::canonical() still defined in terms of absolute(p, base)--)

• --(P0463R1 Endian just Endian

• P0682R1 Repairing elementary string conversions

• P0739R0 Some improvements to class template argument deduction integration into the standard library

• P0674R1 Extending make_shared to Support Arrays

Changes from Kona Feb/Mar 2017

• P0298R3. A byte type definition.

  • Done in r246005

• 2260. Missing requirement for Allocator::pointer

  • We already rely on this, should be nothing to do.

• 2768. any_cast and move semantics

  • Already done? (VilleVoutilainen says: yes, done by LWG 2509 r238022, the extra parts that 2768 drops are QoI)

• 2769. Redundant const in the return type of any_cast(const any&)

  • Already done? (VilleVoutilainen says: yes, done in r243739)

• 2781. Contradictory requirements for std::function and std::reference_wrapper

  • Done in r244364

• 2782. scoped_allocator_adaptor constructors must be constrained

  • Done in r241169

• 2784. Resolution to LWG 2484 is missing "otherwise, no effects" and is hard to parse

  • Nothing to do

• 2785. quoted should work with basic_string_view

• 2786. Annex C should mention shared_ptr changes for array support

  • Nothing to do

• 2787. §[file_status.cons] doesn't match class definition

• 2789. Equivalence of contained objects

  • Nothing to do

• 2794. Missing requirements for allocator pointers

  • Nothing to do

• 2795. §[global.functions] provides incorrect example of ADL use

  • Nothing to do

• 2804. Unconditional constexpr default constructor for istream_iterator

  • No change needed

• 2812. Range access is available with <string_view>

  • No change needed

• 2824. list::sort should say that the order of elements is unspecified if an exception is thrown

  • No change needed

• 2826. string_view iterators use old wording

  • No change needed

• 2834. Resolution LWG 2223 is missing wording about end iterators

  • No change needed

• 2835. LWG 2536 seems to misspecify <tgmath.h>

  • No change needed?

• 2837. gcd and lcm should support a wider range of input values

• 2838. is_literal_type specification needs a little cleanup

  • Nothing to do?

• 2842. in_place_t check for optional::optional(U&&) should decay U

  • done? (VilleVoutilainen says: Yes, r243966)

• 2850. std::function move constructor does unnecessary work

  • Already works this way

• 2853. Possible inconsistency in specification of erase in [vector.modifiers]

  • Nothing to do?

• 2855. std::throw_with_nested("string_literal")

  • Done

• 2796. tuple should be a literal type

  • Seems to be true already.

• 2790. Missing specification of istreambuf_iterator::operator->

  • We never implemented the removed operator, should be nothing to do.

• 2676. Provide filesystem::path overloads for File-based streams

• P0317R1 (Directory Entry Caching for Filesystem).

• P0492R2 (Proposed Resolution of C++17 National Body Comments for Filesystems)

• P0430R2 (File system library on non-POSIX-like operating systems)

• P0604R0 (Resolving GB 55, US 84, US 85, US 86)

  • Done in r246036

• P0607R0 (Inline Variables for the Standard Library)

  • Done in r246423

• P0618R0 (Deprecating <codecvt>)

  • No need to actually do anything

• P0181R1 "Ordered By Default"

  • Was never implemented, no need to revert anything.

• P0156R2 (Variadic Lock guard)

  • Done in r245903

• P0599R1 (noexcept for hash functions)

  • Done?

• P0433R2 (Integrating template deduction for class templates into the standard library)

• 2872. Add definition for direct-non-list-initialization US 107

• 2890. The definition of 'object state' applies only to class types US 111

• 2866. Incorrect derived classes constraints GB 36

• 2857. {variant,optional,any}::emplace should return the constructed value r246182

• 2900. The copy and move constructors of optional are not constexpr US 111 r246556

• 2806. Base class of bad_optional_access GB 49 r246103

• 2934. optional<const T> doesn't compare with T r246076

• 2903. The form of initialization for the emplace-constructors is not specified US 118

• 2904. Make variant move-assignment more exception safe CH 7

• 2868. Missing specification of bad_any_cast::what() GB 54

  • No change needed.

• 2801. Default-constructibility of unique_ptr US 122 r244054

• 2905. is_constructible_v<unique_ptr<P, D>, P, D const &> should be false when D is not copy constructible US 123

• 2873. Add noexcept to several shared_ptr related functions US 124

• 2802. shared_ptr constructor requirements for a deleter US 127

• 2874. Constructor shared_ptr::shared_ptr(Y*) should be constrained US 125

• 2875. shared_ptr::shared_ptr(Y* | D | […]) constructors should be constrained US 126

• 2876. shared_ptr::shared_ptr(const weak_ptr<Y>&) constructor should be constrained US 129

• 2908. The less-than operator for shared pointers could do more US 135

  • Nothing to do?

• 2807. std::invoke should use std::is_nothrow_callable GB 53

• 2861. basic_string should require that charT match traits::char_type US 145

• 2788. basic_string range mutators unintentionally require a default constructible allocator

• 2878. Missing DefaultConstructible requirement for istream_iterator default constructor US 153

• 2921. packaged_task and type-erased allocators US 165

• 2911. An is_aggregate type trait is needed US 143

• P0558R1 (Resolving atomic<T> named base class inconsistencies).

  • Nothing to do?

• P0548R1 (common_type and duration)

  • see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89102

Changes from Issaquah Nov 2016

• 2221. No formatted output operator for nullptr See PR54043 and partial patch without symbol additions

• 2261. Are containers required to use their 'pointer' type internally?

  • JonathanWakely has patches for this

• 2503. multiline option should be added to syntax_option_type

• 2534. Constrain rvalue stream operators

  • naïve attempt to constrain them causes infinite recursion done

• 2686. Why is std::hash specialized for error_code, but not error_condition?

• 2749. swappable traits for variants r243120

• 2759. gcd / lcm and bool for the WP r254736

• 2770. tuple_size<const T> specialization is not SFINAE compatible and breaks decomposition declarations

• 2773. Making std::ignore constexpr

• 2777. basic_string_view::copy should use char_traits::copy

• 2778. basic_string_view is missing constexpr

  • done

• P0426R1 Constexpr for std::char_traits

  • done

• P0403R1 Literal suffixes for basic_string_view

  • done

• P0505R0 (Wording for GB 50 - constexpr for chrono).

  • done.

• P0418R2 Fail or succeed: there is no atomic lattice. (This also resolves LWG issue 2445)

• P0508R0 Wording for GB 58 - structured bindings for node_handles

  • no changes required

• P0503R0 Correcting library usage of "literal type"

  • no changes required

• P0414R2 (Merging shared_ptr changes from Library Fundamentals to C++17) and P0497R0 (Fixes to shared_ptr support for arrays).

  • done

• P0504R0 (Revisiting in-place tag types for any/optional/variant

  • done

• P0003R5 Removing Deprecated Exception Specifications from C++17

  • no changes required

• P0510R0 Disallowing references, incomplete types, arrays, and empty variants

  • done

• P0516R0 Clarify That shared_future's Copy Operations have Wide Contracts

  • done

• P0509R1 Updating "Restrictions on exception handling"

  • No changes needed

• P0502R0 Throwing out of a parallel algorithm terminates—but how?

  • Parallel algos not implemented

• P0517R0 Make future_error Constructible

  • done

• P0521R0 shared_ptr use_count/unique

  • No changes required

• P0513R0 Poisoning the Hash (Also resolves LWG 2791 and LWG 2543).

• P0067R5 Elementary string conversions

  • Only done for integer types, missing floating point support.

• P0435R1 Resolving LWG Issues re common_type. Resolves LWG issues 2465 and 2763.

  • see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89102

Changes from Oulu Jun 2016

• 2549 Tuple EXPLICIT constructor templates that take tuple parameters end up taking references to temporaries and will create dangling references

• 2393 std::function's Callable definition is broken

• 2542 Missing const requirements for associative containers

• 2436 Comparators for associative containers should always be CopyConstructible

• 2550 Wording of unordered container's clear() method complexity

• 2310 Public exposition only member in std::array

  • No changes needed

• 2181 Exceptions from seed sequence operations

• 2328 Rvalue stream extraction should use perfect forwarding

• 2667 path::root_directory() description is confusing

• 2669 recursive_directory_iterator effects refers to non-existent functions

• 2671 Errors in Copy

• 2673 status() effects cannot be implemented as specified

• 2670 system_complete refers to undefined variable 'base'

• 2441 Exact-width atomic typedefs should be provided

• 2426 Issue about compare_exchange

• 2309 mutex::lock() should not throw device_or_resource_busy

• 2710 "Effects: Equivalent to ..." doesn't count "Synchronization:" as determined semantics

• 2685 shared_ptr deleters must not throw on move construction

• 2698 Effect of assign() on iterators/pointers/references

• 2596 vector::data() should use addressof

• 2684 priority_queue lacking comparator typedef

• 2689 Parallel versions of std::copy and std::move shouldn't be in order

• 2688 clamp misses preconditions and has extraneous condition on result

• 2707 path construction and assignment should have "string_type&&" overloads

• 2674 Bidirectional iterator requirement on path::iterator is very expensive

• 2706 Error reporting for recursive_directory_iterator::pop() is under-specified

• 2683 filesystem::copy() says "no effects"

• 2555 [fund.ts.v2] No handling for over-aligned types in optional

• 2451 [fund.ts.v2] optional should 'forward' T's implicit conversions

• 2573 [fund.ts.v2] std::hash<std::experimental::shared_ptr> does not work for arrays

• 2551 [fund.ts.v2] "Exception safety" cleanup in library fundamentals required

• 2516 [fund.ts.v2] Public "exposition only" members in observer_ptr

• 2509 [fund.ts.v2] any_cast doesn't work with rvalue reference targets and cannot move with a value target

• 2687 {inclusive,exclusive}_scan misspecified

• 2704 recursive_directory_iterator's members should require '*this is dereferenceable'

• 2711 path is convertible from approximately everything under the sun

• 2725 filesystem::exists(const path&, error_code&) error reporting

• 2312 tuple's constructor constraints need to be phrased more precisely

  • No changes required

• 2422 std::numeric_limits<T>::is_modulo description: "most machines" errata

• 2709 offsetof is unnecessarily imprecise

• 2716 Specification of shuffle and sample disallows lvalue URNGs

• 2718 Parallelism bug in [algorithms.parallel.exec] p2

• 2719 permissions function should not be noexcept due to narrow contract

• 2720 permissions function incorrectly specified for symlinks

• 2721 remove_all has incorrect post conditions

• 2723 Do directory_iterator and recursive_directory_iterator become the end iterator upon error?

• 2724 The protected virtual member functions of memory_resource should be private

  • No changes required

• 2726 [recursive_]directory_iterator::increment(error_code&) is underspecified

• 2727 Parallel algorithms with constexpr specifier

• 2728 status(p).permissions() and symlink_status(p).permissions() are not specified

• p0063r3, C++17 should refer to C11 instead of C99

• p0175r1, Synopses for the C library

  • see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79700

• p0088r3, Variant: a type-safe union for C++17

• p0307r2, Making Optional Greater Equal Again

• p0393r3, Making Variant Greater Equal

• p0032r3, Homogeneous interface for variant, any and optional

• p0067r3, Elementary string conversions

  • superseded by P0067R5 (above)

• p0254r2, Integrating std::string_view and std::string

• p0258R2, has_unique_object_representations

• p0040r3, Extending memory management tools

• p0084r2, Emplace Return Type

• p0302r1, Removing Allocator Support in std::function

• p0083r3, Splicing Maps and Sets

• p0181r1, Ordered by Default

  • change was reverted

• p0163r0, shared_ptr::weak_type

• p0209r2, make_from_tuple: apply for construction

• p0295r0, Adopt Selected Library Fundamentals V2 Components for C++17

• p0337r0, Delete operator= for polymorphic_allocator

• p0358r1, Fixes for not_fn

• p0219r1, Relative Paths for Filesystem

• p0392r0, Adapting string_view by filesystem paths

• P0394r4, Hotel Parallelifornia: terminate() for Parallel Algorithms Exception Handling

• p0336r1, Better Names for Parallel Execution Policies in C++17

• p0371r1, Temporarily discourage memory_order_consume

  • nothing to do

• p0346r1, A <random> Nomenclature Tweak

  • nothing to do

• p0180r2, Reserve a New Library Namespace for Future Standardization

  • nothing to do

Changes from Jacksonville Feb/Mar 2016

• 2276 Missing requirement on std::promise::set_exception

• 2523 std::promise synopsis shows two set_value_at_thread_exit()'s for no apparent reason

• 2537 Constructors for priority_queue taking allocators should call make_heap

• 2192 Validity and return type of std::abs(0u) is unclear

• 2450 (greater less greater_equal less_equal)<void> do not yield a total order for pointers

• 2520 N4089 broke initializing unique_ptr<T[]> from a nullptr

• 2545 Simplify wording for bind without explicitly specified return type

• 2557 Logical operator traits are broken in the zero-argument case

• 2559 Error in LWG 2234's resolution

  • Nothing to do

• 2560 is_constructible underspecified when applied to a function type

• 2565 std::function's move constructor should guarantee nothrow for reference_wrappers and function pointers

• 2566 Requirements on the first template parameter of container adaptors

• 2571 [map.modifiers]/2 imposes nonsensical requirement on insert(InputIterator, InputIterator)

• 2572 The remarks for shared_ptr::operator* should apply to cv-qualified void as well

  • nothing to do

• 2576 istream_iterator and ostream_iterator should use std::addressof

• 2577 {shared,unique}_lock should use std::addressof

• 2579 Inconsistency wrt Allocators in basic_string assignment vs. basic_string::assign

• 2581 Specialization of <type_traits> variable templates should be prohibited

  • nothing to do

• 2582 [res.on.functions]/2's prohibition against incomplete types shouldn't apply to type traits

• 2583 There is no way to supply an allocator for basic_string(str, pos)

• 2585 forward_list::resize(size_type, const value_type&) effects incorrect

• 2586 Wrong value category used in scoped_allocator_adaptor::construct()

• 2590 Aggregate initialization for std::array

• 2522 [fund.ts.v2] Contradiction in set_default_resource specification

• 2539 [fund.ts.v2] invocation_trait definition definition doesn't work for surrogate call functions

• 2558 [fund.ts.v2] Logical operator traits are broken in the zero-argument case

• 2574 [fund.ts.v2] std::experimental::function::operator=(F&&) should be constrained

• 2575 [fund.ts.v2] experimental::function::assign should be removed

• P0024R2, The Parallelism TS Should be Standardized.

• P0226R1, Mathematical Special Functions for C++17, v5.

• P0220R1, Adopt Library Fundamentals V1 TS Components for C++17 (R1).

  • partially done

• P0218R0, Adopt the File System TS for C++17.

• P0033R1, Re-enabling shared_from_this (revision 1).

• P0005R4, Adopt not_fn from Library Fundamentals 2 for C++17.

• P0152R1, constexpr atomic::is_always_lock_free.

• P0185R1, Adding [nothrow-]swappable traits, revision 3.

• P0253R1, Fixing a design mistake in the searchers interface.

• P0025R0, An algorithm to "clamp" a value between a pair of boundary values

• P0154R1, constexpr std::hardware_{constructive,destructive}_interference_size

• option #2 in P0030R1?, Proposal to Introduce a 3-Argument Overload to std::hypot

• P0031R0, A Proposal to Add Constexpr Modifiers to reverse_iterator, move_iterator, array and Range Access and apply the resolution of LWG Issue 2296

• P0272R1, Give 'std::string' a non-const '.data()' member function.

• P0077R2, is_callable, the missing INVOKE related trait.

Changes from Kona Nov 2015

• 1169 num_get not fully compatible with strto*

• 2072 Unclear wording about capacity of temporary buffers

  • No changes needed

• 2101 Some transformation types can produce impossible types

• 2111 Which unexpected/terminate handler is called from the exception handling runtime?

• 2119 Missing hash specializations for extended integer types

• 2127 Move-construction with raw_storage_iterator

• 2133 Attitude to overloaded comma for iterators

• 2156 Unordered containers' reserve(n) reserves for n-1 elements

• 2218 Unclear how containers use allocator_traits::construct()

• 2219 INVOKE-ing a pointer to member with a reference_wrapper as the object expression

• 2244 Issue on basic_istream::seekg

• 2250 Follow-up On Library Issue 2207

• 2259 Issues in 17.6.5.5 rules for member functions

  • nothing to do

• 2336 is_trivially_constructible/is_trivially_assignable traits are always false

  • nothing to do

• 2353 std::next is over-constrained r254957

• 2367 pair and tuple are not correctly implemented for is_constructible with no args

• 2380 May <cstdlib> provide long ::abs(long) and long long ::abs(long long)?

• 2384 Allocator's deallocate function needs better specification

• 2385 function::assign allocator argument doesn't make sense

• 2435 reference_wrapper::operator()'s Remark should be deleted

• 2447 Allocators and volatile-qualified value types

  • consider adding static assert to enforce it? https://gcc.gnu.org/PR48101

• 2462 std::ios_base::failure is overspecified

• 2466 allocator_traits::max_size() default behavior is incorrect

• 2469 Wrong specification of Requires clause of operator[] for map and unordered_map

  • Let's keep this open for a bit. There's otherwise nothing to do, but the code could use a cleanup, like removing the duplication of "if (__i == end() || key_comp()(__k, (*__i).first))" eight times.

• 2473 basic_filebuf's relation to C FILE semantics

• (2476 scoped_allocator_adaptor is not assignable

• 2477 Inconsistency of wordings in std::vector::erase() and std::deque::erase()

  • nothing to do

• 2483 throw_with_nested() should use is_final

• 2484 rethrow_if_nested() is doubly unimplementable

• 2485 get() should be overloaded for const tuple&& r254222

• 2486 mem_fn() should be required to use perfect forwarding

• 2487 bind() should be const-overloaded, not cv-overloaded

  • libstdc++ ships the volatile overloads as deprecated extensions

• 2489 mem_fn() should be noexcept

• 2492 Clarify requirements for comp

  • nothing to do

• 2224 Ambiguous status of access to non-live objects

  • nothing to do

• 2234 assert() should allow usage in constant expressions

• 2273 regex_match ambiguity

• 2495 There is no such thing as an Exception Safety element

  • nothing to do

• P0004R1, Remove Deprecated iostreams aliases.

• P0006R0, Adopt Type Traits Variable Templates for C++17.

• P0092R1, Polishing <chrono>.

• P0007R1, Constant View: A proposal for a std::as_const helper function template.

• P0156R0, Variadic lock_guard(rev 3).

• p0074r0, Making std::owner_less more flexible

• P0013R1, Logical type traits rev 2

• 2494 [fund.ts.v2] ostream_joiner needs noexcept

• 2500 [fund.ts.v2] fundts.memory.smartptr.shared.obs/6 should apply to _cv_-unqualified void

• 2515 [fund.ts.v2] Certain comparison operators of observer_ptr do not match synopsis

• 2517 [fund.ts.v2] Two propagate_const assignment operators have incorrect return type

• 2526 [fund.ts] Incorrect precondition for experimental::function::swap

• n4531, std::rand replacement, revision 3.

• P0013R1, Logical type traits rev 2

FIXME

Parallel Mode doesn't support move-only types

A number of tests contain the following, which should be addressed by making Parallel Mode C++11-compatible:

• // XXX FIXME: parallel-mode should deal correctly with moveable-only types
  // per C++0x, at minimum smoothly fall back to serial.