C++ Standard Library Issues List (Revision D125)

Table of Contents

Reference ISO/IEC IS 14882:2020(E)

This document is the Table of Contents for the Library Active Issues List, Library Defect Reports and Accepted Issues, and Library Closed Issues List, sorted by priority.

Revised 2024-06-11 at 08:44:43 UTC

Priority 1 (1 issues)

Issue Status Section Title Proposed Resolution Priority Duplicates
4015(i) New [optional.monadic] LWG 3973 broke const overloads of std::optional monadic operations Yes 1

Priority 2 (46 issues)

Issue Status Section Title Proposed Resolution Priority Duplicates
4005(i) New 3.47 [defns.required.behavior] "Required behavior" too narrowly defined No 2
3538(i) New 16.2 [library.c] §[library.c] C library functions are not addressable No 2
3011(i) Open 19.3 [assertions] Requirements for assert(E) inconsistent with C No 2
3507(i) Open [stacktrace.entry.query] P0881R7 ("stacktrace") does not define "actual file name", "actual line number" No 2
4024(i) New [util.smartptr.shared.create] Underspecified destruction of objects created in std::make_shared_for_overwrite/std::allocate_shared_for_overwrite Yes 2
2939(i) New 21.3.3 [meta.type.synop] Some type-completeness constraints of traits are overspecified Yes 2
3099(i) New 21.3.3 [meta.type.synop] is_assignable<Incomplete&, Incomplete&> Yes 2
2153(i) LEWG 22.2.2 [utility.swap] Narrowing of the non-member swap contract No 2
2829(i) Open [optional.observe] LWG 2740 leaves behind vacuous words No 2
2833(i) Open [variant.ctor] Library needs to specify what it means when it declares a function constexpr Yes 2
3215(i) New [variant.ctor] variant default constructor has vague constexpr requirements No 2
3688(i) New 22.8.4 [expected.bad] Exception specifications of copy/move member functions of std::bad_expected_access No 2
3891(i) New [expected.object.general] LWG 3870 breaks std::expected<cv T, E> Yes 2
4026(i) New [expected.object.assign] Assignment operators of std::expected should propagate triviality Yes 2
3680(i) New [func.wrap.move.ctor] Constructor of move_only_function with empty ref-qualifier is over-constrained Yes 2
3081(i) Open 22.13.3 [charconv.from.chars] Floating point from_chars API does not distinguish between overflow and underflow Yes 2
3082(i) Open 22.13.3 [charconv.from.chars] from_chars specification regarding floating point rounding is inconsistent Yes 2
3586(i) New [format.string.std] Formatting character alignment inconsistencies Yes 2
3644(i) New [format.string.std] std::format does not define "integer presentation type" Yes 2
4063(i) New [char.traits.specializations.char] Freestanding std::char_traits<char>::eof depends on non-freestanding EOF No 2
2307(i) LEWG 24 [containers] Should the Standard Library use explicit only when necessary? No 2
4046(i) New [associative.reqmts.except] Effects of inserting into or erasing from flat container adaptors when an exception is thrown need to be more permissive No 2
3804(i) New 24.6.9 [flat.map] flat_foo missing some allocator-extended deduction guides No 2
3802(i) New 24.6.9 [flat.map] flat_foo allocator-extended constructors lack move semantics No 2
4048(i) New 24.6.11 [flat.set] Inconsistent preconditions for transparent insertion of std::flat_map/std::flat_set Yes 2
3813(i) New [span.overview] std::span<volatile T, E> is made ill-formed by P2278R4 when T is a normal class type No 2
2962(i) Open [input.iterators] Iterators of Containers of move-only types do not model InputIterator Yes 2
3863(i) New [const.iterators.alias] Is input_iterator guaranteed to have iter_const_reference_t? No 2
4027(i) SG9 26.2 [ranges.syn] possibly-const-range should prefer returning const R& Yes 2
3666(i) New 26.7.14 [range.join] join_view's difference type is too small No 2
3972(i) New [range.join.with.iterator] Issues with join_with_view::iterator's iter_swap No 2
3797(i) New [range.elements.view] elements_view insufficiently constrained Yes 2
3777(i) Open [range.cartesian.view] Common cartesian_product_view produces an invalid range if the first range is input and one of the ranges is empty Yes 2
3060(i) New 27.10.8 [exclusive.scan] XXX_scan algorithms are specified to work with move-only T, but are specified to make N copies of T into the destination range No 2
3436(i) New 27.11.8 [specialized.construct] std::construct_at should support arrays Yes 2
4014(i) New [rand.eng.sub] LWG 3809 changes behavior of some existing std::subtract_with_carry_engine code Yes 2
3693(i) New 28.7 [c.math] §[c.math] Can any of float/double/long double overloads be fused into template overloads? No 2
3674(i) New [locale.members] Removal of requirement for locale names for construction of locales not explained Yes 2
4070(i) SG16 [fs.path.fmtr.funcs] Transcoding by std::formatter<std::filesystem::path> Yes 2
2708(i) Open [fs.rec.dir.itr.members] recursive_directory_iterator::recursion_pending() is incorrectly specified Yes 2
3057(i) Open [fs.op.copy] Correct copy_options handling Yes 2
3288(i) New 33.5.6 [atomics.wait] atomic<T>::notify_one is unimplementable Yes 2
3508(i) New [atomics.ref.generic.general] atomic_ref<cv T> is not well-specified No 2
4069(i) SG1 33.5.8 [atomics.types.generic] std::atomic<volatile T> should be ill-formed No 2
3003(i) Open 33.10.6 [futures.promise] <future> still has type-erased allocators in promise Yes 2
3444(i) New 19.1.2 [networking.ts::socket.streambuf.members] [networking.ts] net::basic_socket_streambuf::connect(Args&&...) effects are wrong No 2

Priority 3 (357 issues)

Issue Status Section Title Proposed Resolution Priority Duplicates
3513(i) New 3.42 [defns.prog.def.type] Fix definition of program-defined based on its uses Yes 3
3669(i) New 4.1.2 [intro.abstract] std::filesystem operations should be observable behaviour No 3
2506(i) SG1 6.9.2 [intro.multithread] Underspecification of atomics No 3
3105(i) New 16 [library] T1 is convertible to T2 No 3
2136(i) Open 16.3.2 [structure] Postconditions vs. exceptions No 3
3556(i) New [structure.requirements] Specification of when semantic constraints are imposed by use of concepts is unclear No 3
3193(i) New [structure.specifications] Mandates: and Expects: elements are not defined for types Yes 3
3401(i) New [structure.specifications] Is "as if by" equivalent to "equivalent to"? No 3
3977(i) New [bitmask.types] constexpr and noexcept for operators for bitmask types Yes 3
3092(i) Open [bitmask.types] Unclear semantics of enum class bitmask types Yes 3
3620(i) New [character.seq.general] What are execution character sets and execution wide-character sets (after P2314R4)? No 3
3690(i) New [contents] std::make_from_tuple etc. should find all tuple-like std::get overloads Yes 3
3240(i) New [using.headers] Headers declare more than entities No 3
3640(i) New 16.4.4 [utility.requirements] Clarify which exceptions are propagated Yes 3
2146(i) Open [utility.arg.requirements] Are reference types Copy/Move-Constructible/Assignable or Destructible? No 3
2152(i) LEWG [swappable.requirements] Instances of standard container types are not swappable Yes 3
3044(i) New [allocator.requirements] Strange specification of max_size() for an allocator Yes 3
3157(i) New [allocator.requirements] Allocator destroy and fancy pointer operations must be non-throwing Yes 3
2461(i) New [allocator.requirements] Interaction between allocators and container exception safety guarantees No 3
4065(i) New [allocator.requirements.general] Requirements for fancy pointers might be insufficient for self-referential implementation of containers Yes 3
3682(i) New [allocator.requirements.general] A Cpp17Allocator type can't silently ignore an unsupported alignment No 3
3928(i) New [namespace.posix] Non-top-level namespace posix shouldn't be reserved Yes 3
3550(i) New [reserved.names] Names reserved by C for standard library not reserved by C++ No 3
3920(i) New [extern.names] Bad footnotes claiming external linkage for entities defined as macros No 3
3142(i) New [res.on.functions] std::foo<incomplete> should be ill-formed NDR Yes 3
3511(i) New [res.on.arguments] Clarify global permission to move Yes 3
3429(i) New [res.on.requirements] "models" should subsume like "satisfies" Yes 3
2695(i) New [member.functions] "As if" unclear in [member.functions] No 3
2414(i) Open [reentrancy] Member function reentrancy should be implementation-defined Yes 3
3229(i) New [res.on.exception.handling] §[res.on.exception.handling]#3 cannot apply to types with implicitly declared destructors Yes 3
3854(i) New [res.on.exception.handling] §[res.on.exception.handling]/3 should not be applied to all standard library types No 3
3217(i) New 17.3.1 [support.limits.general] <memory> and <execution> should define __cpp_lib_parallel_algorithm Yes 3
3931(i) New 17.3.2 [version.syn] Too many paper bump __cpp_lib_ranges Yes 3
2730(i) Open 17.3.5 [numeric.limits] numeric_limits primary template definition No 3
3922(i) New [numeric.limits.general] It's unclear whether numeric_limits can be specialized by users Yes 3
3923(i) New [numeric.limits.general] The specification of numeric_limits doesn't clearly distinguish between implementation requirements and user requirements Yes 3
3370(i) New 17.4.1 [cstdint.syn] §[cstdint.syn]p2 and §[headers]p5 are not sufficiently clear No 3
3084(i) New 17.5 [support.start.term] Termination in C++ is unclear No 3
2815(i) New 17.5 [support.start.term] quick_exit can deadlock Yes 3
3086(i) New [new.delete.single] Possible problem in §[new.delete.single] Yes 3
2737(i) New [new.delete.single] Consider relaxing object size restrictions for single-object allocation functions No 3
2303(i) New [new.delete.placement] Explicit instantiation of std::vector<UserType> broken? No 3
2508(i) New [new.delete.dataraces] §[new.delete.dataraces] wording needs to be updated No 3
3624(i) New 17.7 [support.rtti] Inconsistency of <typeinfo>, <initializer_list>, and <compare> in the standard library Yes 3
2398(i) Open 17.7.3 [type.info] type_info's destructor shouldn't be required to be virtual Yes 3
4087(i) SG16 17.9.3 [exception] Standard exception messages have unspecified encoding Yes 3
2088(i) Open 17.9.5 [exception.terminate] std::terminate problem No 3
2453(i) New 17.10 [support.initlist] §[iterator.range] and now [iterator.container] aren't available via <initializer_list> No 3
3584(i) New 17.11.3 [cmp.common] Clarify common comparison category conversions Yes 3
3587(i) New 17.11.4 [cmp.concept] std::three_way_comparable_with<T, U, void> can be satisfied but can't be modeled No 3
3491(i) New 17.11.6 [cmp.alg] What is a "decayed type"? No 3
3932(i) New 17.11.6 [cmp.alg] Expression-equivalence is sometimes unimplementable when passing prvalue expressions to comparison CPOs No 3
3653(i) New 17.12.2 [coroutine.syn] <coroutine> is freestanding, but uses std::hash which is not No 3
3945(i) New 17.13.2 [cstdarg.syn] §[cstdarg.syn] 'Compatible types' are undefined No 3
3954(i) New 17.14.1 [support.c.headers.general] Feature-test macros in C headers (<stddef.h> etc.) No 3
3484(i) New 17.14.7 [support.c.headers.other] Should <stddef.h> declare ::nullptr_t? Yes 3
3799(i) New 17.14.7 [support.c.headers.other] Should <math.h> provide 3-argument ::hypot overloads? No 3
3895(i) New 18.3 [concepts.syn] Various relation concepts are missing default values of the second template parameters Yes 3
3608(i) New 18.4.4 [concept.convertible] convertible_to and temporary-bound references No 3
3459(i) New 18.4.4 [concept.convertible] Why doesn't std::convertible_to have semantic requirement when To is reference-to-function type? No 3
3019(i) New [syserr.errcat.derived] Presentation of "program defined classes derived from error_category" [syserr.errcat.derived] unclear and contains mistakes No 3
3053(i) New [syserr.errcode.overview] Prohibit error_code construction from rvalues of error_category Yes 3
3162(i) New [syserr.syserr.members] system_error::system_error(error_code ec) not explicit Yes 3
3625(i) New 19.6.2 [stacktrace.syn] Should <stacktrace> provide range access function templates? Yes 3
3626(i) New [stacktrace.basic.overview] Is std::basic_stacktrace required to use contiguous storage? Yes 3
2421(i) New 20.2.5 [ptr.align] Non-specification of handling zero size in std::align [ptr.align] No 3
3192(i) New [allocator.uses.construction] §[allocator.uses.construction] functions misbehave for const types Yes 3
3665(i) New [allocator.traits.types] Is std::allocator_traits<Alloc>::rebind_alloc SFINAE-friendly? No 3
3917(i) New 20.2.10 [default.allocator] Validity of allocator<void> and possibly polymorphic_allocator<void> should be clarified Yes 3
3916(i) New 20.2.10 [default.allocator] allocator, polymorphic_allocator, and containers should forbid cv-qualified types No 3
3684(i) New [allocator.members] std::allocator<T>::allocate_at_least in constant evaluation Yes 3
3159(i) New [unique.ptr.single] §[unique.ptr.single] requirements on deleter may be too strict No 3
2262(i) Open [unique.ptr.single] Requirement for unique_ptr<T>::get_deleter()(p) to be able to destroy the unique_ptr Yes 3
3911(i) New [unique.ptr.single.observers] unique_ptr's operator* is missing a mandate Yes 3
2594(i) New [util.smartptr.shared] Contradicting definition of empty shared_ptr on shared_ptr(nullptr, d) Yes 3
2906(i) New [util.smartptr.shared.const] There is no ability to supply an allocator for the control block when constructing a shared_ptr from a unique_ptr No 3
3216(i) New [util.smartptr.shared.create] Rebinding the allocator before calling construct/destroy in allocate_shared Yes 3
3210(i) New [util.smartptr.shared.create] allocate_shared is inconsistent about removing const from the pointer passed to allocator construct and destroy Yes 3
3637(i) New 20.4.2 [mem.res.class] pmr::memory_resource::do_allocate needs clarification No 3
3634(i) New 20.4.4 [mem.res.global] When are static-duration memory_resource objects destroyed? No 3
2848(i) New [mem.res.pool.options] Pass-through threshold for pool allocator No 3
2452(i) Core 21 [meta] is_constructible, etc. and default arguments No 3
2290(i) Open 21 [meta] Top-level "SFINAE"-based constraints should get a separate definition in Clause 17 Yes 3
2845(i) New 21.3.2 [meta.rqmts] enable_if, result_of, common_type and aligned_storage do not meet the definition of TransformationTrait No 3
2496(i) New [meta.unary.prop] Certain hard-to-avoid errors not in the immediate context are not allowed to be triggered by the evaluation of type traits No 3
3929(i) New [meta.unary.prop] Preconditions for type traits should be Mandates Yes 3
2827(i) New [meta.unary.prop] is_trivially_constructible and non-trivial destructors No 3
3697(i) New [meta.unary.prop] Preconditions of reference_constructs_from_temporary/reference_converts_from_temporary seem wrong Yes 3
2077(i) Open [meta.unary.prop] Further incomplete constraints for type traits No 3
2358(i) Open [meta.unary.prop] Apparently-bogus definition of is_empty type trait Yes 3
2116(i) Open [meta.unary.prop] is_nothrow_constructible and destructors No 3
3174(i) New 21.3.7 [meta.rel] Precondition on is_convertible is too strong Yes 3
3400(i) New 21.3.7 [meta.rel] Does is_nothrow_convertible consider destruction of the destination type? No 3
3205(i) New [meta.trans.other] decay_t in the new common_type fallback should be remove_cvref_t Yes 3
2599(i) New 22.2.6 [declval] Library incomplete type permission phrase is unclear No 3
3342(i) New 22.3.2 [pairs.pair] Library wording uses "initializes x with y", which is underspecified No 3
2289(i) Open 22.3.2 [pairs.pair] constexpr guarantees of defaulted functions still insufficient No 3
2766(i) New 22.3.3 [pairs.spec] Swapping non-swappable types Yes 3
3166(i) New 22.3.4 [pair.astuple] No such descriptive element as Value: No 3
3378(i) New 22.4.2 [tuple.syn] tuple_size_v/tuple_element_t should be available when tuple_size/tuple_element are Yes 3
2528(i) New [tuple.cnstr] Order of std::tuple construction unspecified No 3
3583(i) New [tuple.cnstr] Clarify if/when short circuiting applies to conditions in Constraints: elements No 3
2933(i) New 22.4.5 [tuple.creation] PR for LWG 2773 could be clearer Yes 3
4040(i) New 22.4.7 [tuple.helper] Contradictory specification of std::tuple_size No 3
2472(i) New 22.4.9 [tuple.rel] Heterogeneous comparisons in the standard library can result in ambiguities No 3
3882(i) New 22.4.9 [tuple.rel] tuple relational operators have confused friendships Yes 3
2990(i) Open 22.5.3 [optional.optional] optional::value_type is not always a value type Yes 3
3886(i) New [optional.optional.general] Monad mo' problems Yes 3
2811(i) New [optional.ctor] "Selected constructor" wording is incorrect for optional/variant/any Yes 3
2746(i) New [optional.assign] Inconsistency between requirements for emplace between optional and variant Yes 3
3424(i) New [optional.observe] optional::value_or should never return a cv-qualified type Yes 3
3613(i) New 22.5.4 [optional.nullopt] Specify that nullopt_t is copyable Yes 3
3627(i) New 22.5.9 [optional.specalg] Inconsistent specifications for std::make_optional overloads Yes 3
2881(i) New 22.6.3 [variant.variant] Adopt section III of P0308R0 No 3
3069(i) New [variant.assign] Move assigning variant's subobject corrupts data Yes 3
3991(i) New [variant.assign] variant's move assignment should not be guaranteed to produce a valueless by exception state Yes 3
3416(i) New 22.7.4 [any.class] The Throws: specification of std::any does not mention allocation No 3
3423(i) New 22.7.5 [any.nonmembers] std::any_cast should never return a cv-qualified type Yes 3
2348(i) Open 22.9.2 [template.bitset] charT('1') is not the wide equivalent of '1' Yes 3
4007(i) New 22.10.4 [func.require] Mystic prohibition of calling a volatile-qualified perfect forwarding call wrapper Yes 3
3046(i) New 22.10.6 [refwrap] Do not require reference_wrapper to support non-referenceable function types Yes 3
2491(i) New 22.10.8 [comparisons] std::less<T*> in constant expression Yes 3
2547(i) New 22.10.8 [comparisons] Container requirements (and other library text) should say "strict total order", not just "total order" No 3
3493(i) New [func.wrap.func.con] The constructor of std::function taking an F is missing a constraint Yes 3
3642(i) New [func.wrap.move.ctor] move_only_function assignment operators seem to be defined suboptimal Yes 3
3512(i) New 22.10.19 [unord.hash] Incorrect exception safety guarantee for unordered containers No 3
3456(i) New 22.13.3 [charconv.from.chars] Pattern used by std::from_chars is underspecified Yes 3
3651(i) New 22.14 [format] Unspecified lifetime guarantees for the format string No 3
3641(i) New 22.14.1 [format.syn] Add operator== to format_to_n_result Yes 3
4090(i) SG16 [format.string.std] Underspecified use of locale facets for locale-dependent std::format No 3
3939(i) New [format.string.std] §[format.string.std] char is not formatted as a character when charT is wchar_t No 3
3993(i) New [formatter.requirements] The parse function of a BasicFormatter type needs to be constexpr Yes 3
3943(i) New [format.formattable] Clarify lifetime requirements of BasicFormatter and Formatter Yes 3
3706(i) New [format.formatter.spec] How does std::format work with character arrays of unknown bound? No 3
3942(i) New 23.2.4 [char.traits.specializations] Inconsistent use of const char_type& in standard specializations of std::char_traits Yes 3
2959(i) New [char.traits.specializations.char16.t] char_traits<char16_t>::eof is a valid UTF-16 code unit No 3
3989(i) New 23.3 [string.view] The whole range for an iterator obtained from a std::span or std::basic_string_view is not clear No 3
3457(i) New 23.3.3 [string.view.template] *this is not invalidated Yes 3
3339(i) New 23.4.3 [basic.string] Move-constructed empty-container capacity No 3
3451(i) New 23.4.3 [basic.string] Inconsistently explicit deduction guides Yes 3
4029(i) New [basic.string.general] basic_string accidentally fails to meet the reversible container requirements Yes 3
3663(i) New [string.cons] basic_string(const T&, const Alloc&) turns moves into copies Yes 3
3662(i) New [string.append] basic_string::append/assign(NTBS, pos, n) suboptimal Yes 3
3837(i) New [string.erasure] std::erase_if overloads for non-associative containers should move (and not copy) their predicate object Yes 3
2238(i) Open 23.5 [c.strings] Problematic iterator-pair constructor of containers No 3
3059(i) New 24.2 [container.requirements] Wrong requirements for map-like associative container assignment? No 3
1521(i) Open 24.2.2 [container.requirements.general] Requirements on internal pointer representations in containers Yes 3
2321(i) Open 24.2.2 [container.requirements.general] Moving containers should (usually) be required to preserve iterators Yes 3
2206(i) Open 24.2.4 [sequence.reqmts] Inaccuracy in initializer_list constructor requirements Yes 3
2705(i) New 24.2.4 [sequence.reqmts] Questionable precondition on Sequence containers a.assign(n, t) Yes 3
3297(i) New 24.2.4 [sequence.reqmts] Useless sequence container requirement Yes 3
3438(i) New [container.node.overview] §[container.node.overview] missing multiset/map cases No 3
2227(i) Open 24.2.7 [associative.reqmts] Stateful comparison objects in associative containers No 3
2215(i) Open 24.2.7 [associative.reqmts] (unordered) associative container functors should be CopyConstructible Yes 3
3227(i) New 24.2.7 [associative.reqmts] Ambiguity issue for extract in ordered and unordered associative containers Yes 3
2362(i) New 24.2.7 [associative.reqmts] unique, associative emplace() should not move/copy the mapped_type constructor arguments when no insertion happens No 3
2844(i) Open 24.2.7 [associative.reqmts] Stability of a_uniq.insert(i, j) No 3
3577(i) New [associative.reqmts.general] Merging an (unordered) associative container with itself No 3
3691(i) New [associative.reqmts.general] Replacement of keys in associative containers Yes 3
3578(i) New [associative.reqmts.general] Iterator SCARYness in the context of associative container merging No 3
2198(i) Open 24.2.8 [unord.req] max_load_factor(z) makes no strong guarantees, but bans useful behavior Yes 3
1175(i) Open 24.2.8 [unord.req] unordered complexity Yes 3
2189(i) Open [unord.req.except] Throwing swap breaks unordered containers' state No 3
617(i) Open 24.3.7 [array] std::array is a sequence that doesn't satisfy the sequence requirements? No 3
3219(i) New [array.overview] std::array overview container requirements are incorrect Yes 3
2823(i) Open [array.overview] std::array initialization is still not permissive enough Yes 3
3488(i) Open [array.special] Is array<const int, 0> swappable or not? Yes 3
2157(i) Open [array.zero] How does std::array<T,0> initialization work when T is not default-constructible? Yes 3
3308(i) New [deque.modifiers] vector and deque iterator erase invalidates elements even when no change occurs Yes 3
3758(i) New [vector.capacity] Element-relocating operations of std::vector and std::deque should conditionally require Cpp17CopyInsertable in their preconditions No 3
2158(i) Open [vector.capacity] Conditional copy/move in std::vector Yes 3
1102(i) Open [vector.capacity] std::vector's reallocation policy still unclear Yes 3
3638(i) New 24.3.12 [vector.bool] vector<bool>::swap(reference, reference) is useless Yes 3
1422(i) Open 24.3.12 [vector.bool] vector<bool> iterators are not random access No 3
3531(i) New [map.overview] LWG 3025 broke previous valid code Yes 3
2713(i) New 24.5 [unord] More missing allocator-extended constructors for unordered containers Yes 3
3189(i) New 24.6.7 [priority.queue] Missing requirement for std::priority_queue No 3
3161(i) Open 24.6.8 [stack] Container adapters mandate use of emplace_back but don't require it Yes 3
3966(i) New [flat.map.overview] The value_type and reference members of std::flat_(multi)map::(const_)iterator are unclear No 3
3963(i) New [flat.map.defn] Different std::flat_map/std::flat_multimap specializations should be able to share same nested classes Yes 3
4000(i) New [flat.map.modifiers] flat_map::insert_range's Effects is not quite right Yes 3
3995(i) New 24.7.3 [views.multidim] Issue with custom index conversion in <mdspan> No 3
3952(i) New 25.2 [iterator.synopsis] iter_common_reference_t does not conform to the definition of indirectly_readable Yes 3
3838(i) New [incrementable.traits] The last specialization of incrementable_traits is under-constrained Yes 3
3615(i) New [incrementable.traits] The last specialization of incrementable_traits has wrong operand types Yes 3
3287(i) New [iterator.traits] Exposition-only cpp17-input-iterator concept is needlessly complex Yes 3
3890(i) New [iterator.concept.winc] ABI issue for integer-class types Yes 3
3716(i) New [iterator.concept.forward] §[iterator.concept.forward][forward.iterators] Two different definitions of multi-pass guarantee No 3
484(i) Open [input.iterators] Convertible to T No 3
2035(i) Open [output.iterators] Output iterator requirements are broken Yes 3
2038(i) Open [output.iterators] Missing definition for incrementable iterator No 3
3197(i) New 25.4.3 [iterator.operations] std::prev should not require BidirectionalIterator Yes 3
3439(i) New 25.4.3 [iterator.operations] "Distance" template parameter is underspecified No 3
3344(i) New 25.4.3 [iterator.operations] advance(i, most-negative) and prev(i, most-negative) Yes 3
2931(i) Open 25.4.3 [iterator.operations] Missed optimization opportunity with single-argument std::next No 3
3623(i) New [reverse.iterators.general] Uses of std::reverse_iterator with containers should not require manually including <iterator> Yes 3
2595(i) New [reverse.iterator] reverse_iterator::operator[]'s return type revisited Yes 3
3602(i) New [reverse.iter.cons] reverse_iterator's converting assignment is overconstrained Yes 3
3725(i) New [reverse.iter.elem] reverse_iterator::operator-> should not use prev for non-pointer iterators Yes 3
3986(i) New 25.5.3 [const.iterators] basic_const_iterator doesn't work with optional No 3
3988(i) Open 25.5.3 [const.iterators] Should as_const_view and basic_const_iterator provide base()? Yes 3
3783(i) New [common.iterator] views::common may not be a range adaptor object Yes 3
3748(i) New [common.iter.cmp] common_iterator and counted_iterator' operator- are missing cast to return type Yes 3
3188(i) New 25.6.4 [istreambuf.iterator] istreambuf_iterator::pointer should not be unspecified Yes 3
2366(i) New 25.6.4 [istreambuf.iterator] istreambuf_iterator end-of-stream equality Yes 3
3108(i) New [istreambuf.iterator.proxy] istreambuf_iterator::proxy::operator* should be const Yes 3
3537(i) New 25.7 [iterator.range] §[iterator.range] Missing noexcept for std::rbegin/rend for arrays and initializer_list No 3
4010(i) New [range.subrange.access] subrange::advance should be improved Yes 3
4008(i) New [range.utility.conv.to] §[range.utility.conv.to] ranges::to may cause infinite recursion if range_value_t<C> is a non-move-constructible range Yes 3
4018(i) New [range.utility.conv.to] ranges::to's copy branch is underconstrained Yes 3
3985(i) New [range.utility.conv.to] ranges::to should Mandates C not to be view Yes 3
3983(i) New [range.utility.conv.adaptors] ranges::to adaptors are underconstrained Yes 3
3907(i) New 26.6 [range.factories] Can iterator types of range adaptors and range factories be SCARY? No 3
3614(i) New [range.iota.view] iota_view::size and the most negative signed integer values Yes 3
3846(i) New [range.iota.iterator] iota_view::iterator::operator- is overconstrained Yes 3
4002(i) New [range.iota.iterator] The definition of iota_view::iterator::iterator_concept should be improved Yes 3
3609(i) New [range.iota.sentinel] std::ranges::iota_view<int, long> has non-subtractable iterator and sentinel types Yes 3
3955(i) New [range.repeat.view] Add noexcept to several repeat_view[::iterator] member functions Yes 3
3763(i) New [range.repeat.iterator] Should range adaptor iterators only provide iterator_category when its difference_type is not an integer-class type? Yes 3
3679(i) LEWG 26.6.6 [range.istream] Is <ranges> sufficient for istream_view? No 3
3489(i) New [range.istream.iterator] Improve istream_view wording Yes 3
3829(i) New [range.as.rvalue.view] as_rvalue_view::end should improve non-common case Yes 3
3730(i) New [range.drop.view] std::ranges::drop_view may have different size type from its underlying view Yes 3
3971(i) Open [range.join.with.view] Join ranges of rvalue references with ranges of prvalues No 3
3873(i) New [range.join.with.view] join_with_view's const begin is underconstrained No 3
3852(i) New [range.join.with.iterator] join_with_view::iterator's iter_move and iter_swap should be conditionally noexcept Yes 3
3599(i) New [range.lazy.split.view] The const overload of lazy_split_view::begin should be constrained by const Pattern Yes 3
3685(i) New [range.lazy.split.view] In lazy_split_view, CTAD doesn't work when given an input_range input and a tiny-range pattern Yes 3
3686(i) New [range.lazy.split.outer] In lazy_split_view, comparing a default-constructed outer-iterator or inner-iterator with std::default_sentinel results in null pointer dereference Yes 3
4017(i) New [range.split.iterator] Behavior of std::views::split on an empty range Yes 3
4019(i) SG9 26.7.21 [range.reverse] Reversing an infinite range leads to an infinite loop No 3
3830(i) New [range.reverse.view] reverse_view should not cache when ranges::next has constant time complexity Yes 3
3832(i) New [range.elements.iterator] Missing change for element_view::iterator in LWG 3798 Yes 3
3731(i) New [range.zip.view] zip_view and adjacent_view are underconstrained Yes 3
3900(i) New 26.8.5 [coro.generator.promise] The allocator_arg_t overloads of generator::promise_type::operator new should not be constrained Yes 3
3899(i) New 26.8.5 [coro.generator.promise] co_yielding elements of an lvalue generator is unnecessarily inefficient Yes 3
1238(i) Open 27 [algorithms] Defining algorithms taking iterator for range No 3
2963(i) New 27 [algorithms] Algorithms with underspecified iterator requirements No 3
3049(i) Open 27.2 [algorithms.requirements] Missing wording allowing algorithms to use copies of function objects as substitutes for their parameters Yes 3
3793(i) New 27.6.5 [alg.foreach] Requirements for some algorithms' Size template parameters are unclear No 3
3969(i) New 27.6.18 [alg.fold] std::ranges::fold_left_first_with_iter should be more ADL-proof Yes 3
3089(i) New 27.7.1 [alg.copy] copy_n should require non-overlapping ranges Yes 3
2471(i) Open 27.7.1 [alg.copy] copy_n's number of InputIterator increments unspecified No 3
2267(i) New [partial.sort.copy] partial_sort_copy underspecified for ranges of two different types No 3
3534(i) LEWG [set.intersection] ranges::set_intersection and ranges::set_difference algorithm requirements are too strict Yes 3
3029(i) Open [pop.heap] pop_heap over-constrains input Yes 3
3487(i) New 27.10 [numeric.ops] Missing precondition on input and output aliasing of [numeric.ops] No 3
3463(i) New 27.10.11 [transform.inclusive.scan] Incorrect requirements for transform_inclusive_scan without initial value Yes 3
3063(i) New 27.11 [specialized.algorithms] Parallel algorithms in <memory> are underspecified No 3
3064(i) New 27.11 [specialized.algorithms] How do uninitialized memory algorithms obtain pointer without undefined behavior? No 3
3628(i) New 27.11 [specialized.algorithms] "Effects: Equivalent to:" and uninitialized memory algorithms No 3
3647(i) New 27.11.2 [special.mem.concepts] nothrow-input-iterator constraints should not mention copying Yes 3
3918(i) Open 27.11.6 [uninitialized.move] std::uninitialized_move/_n and guaranteed copy elision Yes 3
3888(i) New 27.11.8 [specialized.construct] Most ranges uninitialized memory algorithms are underconstrained Yes 3
3889(i) New 27.11.9 [specialized.destroy] std::(ranges::)destroy_at should destroy array elements in the decreasing index order Yes 3
3934(i) New 28.4.3 [complex] std::complex<T>::operator=(const T&) has no specification Yes 3
2714(i) New 28.4.6 [complex.ops] complex stream extraction underspecified Yes 3
2846(i) New 28.4.10 [cmplx.over] Undefined phrase "effectively cast" Yes 3
3402(i) New [rand.dist.bern.negbin] Wording for negative_binomial_distribution is unclear as a consequence of LWG 2406 resolution No 3
2847(i) New 28.7.1 [cmath.syn] sin(float) should call sinf(float) No 3
3093(i) New 28.7.2 [c.math.abs] LWG 2294/2192 missed a std::abs overload No 3
3172(i) New 28.7.3 [c.math.hypot3] 3-arg std::hypot is underspecified compared to the 2-arg overload Yes 3
3066(i) New 28.7.6 [sf.cmath] "report a domain error" in [sf.cmath]/1 is underspecified No 3
3090(i) New 29.5.2 [time.duration.cons] What is §[time.duration.cons]p4's "no overflow is induced in the conversion" intended to mean? Yes 3
3503(i) New 29.5.8 [time.duration.cast] chrono::ceil has surprising requirement No 3
2383(i) Open 29.5.9 [time.duration.literals] Overflow cannot be ill-formed for chrono::duration integer literals No 3
3856(i) New 29.12 [time.format] Unclear which conversion specifiers are valid for each chrono type Yes 3
3921(i) New 29.12 [time.format] Is std::chrono::duration<std::int64_t, std::ratio<INT64_MAX - 1, INT64_MAX>>{40} required to be correctly formatted? No 3
3831(i) New 29.12 [time.format] Two-digit formatting of negative year is ambiguous Yes 3
3844(i) Open 29.12 [time.format] Non-numeric formats for negative durations Yes 3
3956(i) New 29.13 [time.parse] chrono::parse uses from_stream as a customization point No 3
3962(i) New 29.13 [time.parse] What is the "decimal precision of the input"? Yes 3
3960(i) New 29.13 [time.parse] How does chrono::parse handle duplicated data? Yes 3
3961(i) New 29.13 [time.parse] Does chrono::parse check format strings? Yes 3
3353(i) New 30.3.1 [locale] locale's copy assignment operator should return locale& Yes 3
3337(i) New [locale.codecvt.virtuals] What is "is initialized" supposed to mean? No 3
3689(i) New [facet.num.get.virtuals] num_get overflow determination unclear and incorrect No 3
4084(i) LEWG [facet.num.put.virtuals] std::fixed ignores std::uppercase Yes 3
2117(i) Open [facet.num.put.virtuals] ios_base manipulators should have showgrouping/noshowgrouping No 3
2702(i) New [facet.num.put.virtuals] num_put::do_put(..., bool) performs ill-formed do_put call No 3
2703(i) New [facet.num.put.virtuals] No provision for fill-padding when boolalpha is set No 3
3275(i) New [locale.time.get.virtuals] Why does time_get::do_get require a valid pointer when none of the others do? Yes 3
2983(i) New [locale.money.put.virtuals] money_put::do_put underspecified Yes 3
2691(i) New [locale.moneypunct] money_base::space and do_put: U+0020 versus fill Yes 3
423(i) Open 31 [input.output] Effects of negative streamsize in iostreams Yes 3
3696(i) New 31.2.2 [stream.types] "Basic integral types" should not be used No 3
2675(i) New [ios.base.callback] register_callback can fail No 3
2504(i) New 31.6.3 [streambuf] basic_streambuf is not an abstract class No 3
3658(i) New [streambuf.pub.put] basic_streambuf::sputn is both overspecified and underspecified Yes 3
2497(i) New [ostream.sentry] Use of uncaught_exception() Yes 3
4101(i) New [ostream.inserters.arithmetic] LWG 117 loses the sign for negative NaN on some architectures Yes 3
3501(i) New [ostream.manip] basic_syncbuf-related manipulators refer to some Allocator without defining it Yes 3
3937(i) New 31.7.7 [std.manip] I/O manipulators should be specified in terms of base classes No 3
2984(i) New 31.7.8 [ext.manip] put_money(99) is unnecessarily undefined Yes 3
4042(i) LEWG 31.7.10 [print.fun] std::print should permit an efficient implementation Yes 3
4044(i) Open 31.7.10 [print.fun] Confusing requirements for std::print on POSIX platforms Yes 3
3309(i) New 31.8 [string.streams] Is <ios> implicitly #included by <sstream>, <fstream> etc.? No 3
3097(i) New [stringbuf.virtuals] basic_stringbuf seekoff effects trigger undefined behavior and have contradictory returns No 3
3496(i) New [syncstream.syncbuf.members] What does "uniquely associated" mean for basic_syncbuf::emit()? No 3
3497(i) New [syncstream.syncbuf.members] Postconditions for basic_syncbuf::emit() No 3
3098(i) New [fs.path.decompose] Misleading example for filesystem::path::filename() Yes 3
3699(i) New [fs.path.gen] lexically_relative on UNC drive paths (\\?\C:\...) results in a default-constructed value No 3
3794(i) New [fs.path.itr] std::filesystem::path::iterator::reference should be allowed to be std::filesystem::path Yes 3
2947(i) New [fs.enum.path.format] Clarify several filesystem terms No 3
3078(i) New 31.12.10 [fs.class.directory.entry] directory_entry, directory_iterator and recursive_directory_iterator perform needless path copies No 3
3668(i) New [fs.dir.itr.members] [recursive_]directory_iterator constructors refer to undefined options Yes 3
3056(i) New [fs.op.copy.file] copy_file() copies which attributes? Yes 3
3744(i) New [fs.op.copy.symlink] copy_symlink(junction, new_symlink)'s behavior is unclear No 3
2490(i) New 32 [re] <regex> needs lots of noexcept No 3
2431(i) New 32.2 [re.req] Missing regular expression traits requirements No 3
3606(i) New 32.2 [re.req] Missing regex_traits::locale_type requirements No 3
3998(i) New 32.4 [re.const] Constants in std::regex_constants should be allowed to be enumerators No 3
2331(i) Open 32.4.2 [re.synopt] regex_constants::collate's effects are inaccurately summarized Yes 3
3605(i) New 32.4.3 [re.matchflag] regex_constants::match_prev_avail is underspecified No 3
2338(i) Open 32.6 [re.traits] §[re.traits]/7 expects of locale facets something not guaranteed by [locale.facet]/4 Yes 3
3261(i) New 32.7 [re.regex] regex components' noexcept annotations appear broken for POCMA or throwing BidirectionalIterator No 3
3603(i) New 32.7.2 [re.regex.construct] Matching of null characters by regular expressions is underspecified No 3
3341(i) New 32.7.2 [re.regex.construct] basic_regex range constructor: Missing requirements for iterator types No 3
3604(i) New 32.7.2 [re.regex.construct] What is the effect of an invalid value of type syntax_option_type? No 3
2137(i) Open 32.7.3 [re.regex.assign] Misleadingly constrained post-condition in the presence of exceptions Yes 3
3126(i) New 32.8 [re.submatch] There's no std::sub_match::compare(string_view) overload Yes 3
2216(i) New 32.10.4 [re.alg.replace] regex_replace(basic_string) allocator handling No 3
2220(i) Open [re.tokiter.comp] Under-specification of operator== for regex_token_iterator Yes 3
2987(i) New 32.12 [re.grammar] Relationship between traits_inst.lookup_collatename and the regex FSM is underspecified with regards to ClassAtomCollatingElement No 3
2819(i) New 33.2.5 [thread.req.lockable] Unspecified Return type: elements Yes 3
3499(i) New [thread.req.lockable.timed] Timed lockable and mutex requirements are imprecise about duration and time_point No 3
3924(i) New 33.3.1 [thread.stoptoken.intro] Stop token data race avoidance requirements unclear Yes 3
3516(i) New [thread.thread.id] thread::id spaceship may be inconsistent with equality Yes 3
3475(i) New [thread.thread.constr] std::thread's constructor needs to be able to report general memory allocation failures Yes 3
3633(i) New 33.5 [atomics] Atomics are copy constructible and copy assignable from volatile atomics Yes 3
3220(i) New 33.5.2 [atomics.syn] P0558 broke conforming C++14 uses of atomic shared_ptr Yes 3
4004(i) SG1 33.5.4 [atomics.order] The load and store operation in §[atomics.order] p1 is ambiguous No 3
3941(i) SG1 33.5.4 [atomics.order] §[atomics.order] inadvertently prohibits widespread implementation techniques No 3
3263(i) New 33.5.6 [atomics.wait] Atomic waiting function calls should only be unblocked once Yes 3
3485(i) SG1 33.5.7 [atomics.ref.generic] atomic_ref safety should be based on operations that "potentially conflict" rather than lifetime No 3
3409(i) New [atomics.ref.ops] Too lax description of atomic_ref<T>::required_alignment Yes 3
3417(i) SG1 [atomics.types.operations] Missing volatile atomic deprecations Yes 3
3047(i) New [atomics.types.int] atomic compound assignment operators can cause undefined behavior when corresponding fetch_meow members don't Yes 3
3906(i) New [atomics.types.pointer] "Undefined address" is undefined No 3
3418(i) New 33.5.9 [atomics.nonmembers] Deprecated free functions in <atomic> Yes 3
3343(i) Open 33.7.3 [thread.condition.nonmember] Ordering of calls to unlock() and notify_all() in Effects element of notify_all_at_thread_exit() should be reversed Yes 3
3504(i) New 33.7.4 [thread.condition.condvar] condition_variable::wait_for is overspecified No 3
3898(i) New [thread.barrier.class] Possibly unintended preconditions for completion functions of std::barrier Yes 3
2530(i) Open 33.10.5 [futures.state] Clarify observable side effects of releasing a shared state No 3
2532(i) Open 33.10.6 [futures.promise] Satisfying a promise at thread exit Yes 3
3582(i) New 33.10.9 [futures.async] Unclear where std::async exceptions are handled Yes 3
2507(i) New 99 [depr.locale.stdcvt] codecvt_mode should be a bitmask type No 3
3840(i) Open D.21 [depr.fs.path.factory] filesystem::u8path should be undeprecated Yes 3
3812(i) New [fund.ts.v3::propagate_const.const_observers] [fund.ts.v3] Incorrect constraint on propagate_const conversion function Yes 3
3167(i) Open 5.2 [fund.ts.v3::memory.observer.ptr] [fund.ts.v3] Does observer_ptr support function types? No 3
3357(i) Open 99 [fund.ts.v3::rand.util.randint] [fund.ts.v3] default_random_engine is overspecified for per-thread engine Yes 3
3124(i) New 13.7.5 [networking.ts::async.exec.ctx.globals] [networking.ts] Unclear how execution_context is intended to store services Yes 3
3021(i) New 16.2.2 [networking.ts::buffer.reqmts.constbuffersequence] [networking.ts] Relax pointer equivalence requirement for ConstBufferSequence Yes 3
3072(i) New 16.2.4 [networking.ts::buffer.reqmts.dynamicbuffer] [networking.ts] DynamicBuffer object lifetimes underspecified Yes 3
3027(i) New 16.2.4 [networking.ts::buffer.reqmts.dynamicbuffer] [networking.ts] DynamicBuffer prepare exception specification Yes 3
3073(i) New 17 [networking.ts::buffer.stream] [networking.ts] (async_)read and (async_)write don't support DynamicBuffer lvalues Yes 3
3445(i) LEWG 19.2.1 [networking.ts::socket.iostream.cons] [networking.ts] net::basic_socket_istream::connect should be constrained Yes 3

Priority 4 (66 issues)

Issue Status Section Title Proposed Resolution Priority Duplicates
2949(i) New 16 [library] Unclear complexity requirements: space vs. time No 4
3267(i) New [allocator.requirements] Rebound allocators and is_always_equal Yes 4
4047(i) New [namespace.std] Explicitly specifying template arguments for std::swap should not be supported No 4
3926(i) New [namespace.std] Which namespace std is the mentioned one? Yes 4
2248(i) New 17.3.5 [numeric.limits] numeric_limits::is_iec559 misnamed No 4
2493(i) New 17.10 [support.initlist] initializer_list supports incomplete classes No 4
3883(i) New 17.14.7 [support.c.headers.other] §[support.c.headers.other] Ambiguity in the requirements for includes Yes 4
4041(i) New 18.4.9 [concept.swappable] The requirements on literal type in [concept.swappable] should be removed Yes 4
4032(i) New [util.smartptr.shared.const] Possibly invalid types in the constraints of constructors of std::shared_ptr Yes 4
2751(i) New [util.smartptr.shared.dest] shared_ptr deleter not specified to observe expired weak_ptr instances No 4
3681(i) New 20.4.1 [mem.res.syn] Further considerations on LWG 3679 No 4
3902(i) New 22.2.6 [declval] Return type of std::declval<cv void> should be (cv-unqualified) void Yes 4
3978(i) New 22.4.5 [tuple.creation] The "no effect" requirement for std::ignore is unimplementable for volatile bit-fields No 4
3728(i) New 22.4.9 [tuple.rel] Can't make neither head nor tail of the description of operator<=>(tuple, tuple) Yes 4
3805(i) New 22.10 [function.objects] Expression evaluating to a call wrapper is a prvalue, not an object No 4
3979(i) New 22.10.13 [func.not.fn] Should we reject std::bind_front<42>() and its friends? Yes 4
3997(i) New 22.14.1 [format.syn] std::formatter specializations should be consistently restricted to supported character types No 4
3968(i) New 22.15.8 [bit.endian] std::endian::native value should be more specific about object representations Yes 4
2513(i) New 23.1 [strings.general] Missing requirements for basic_string::value_type No 4
3694(i) New 23.2.2 [char.traits.require] Should traits_type::length be customizable? No 4
2237(i) New 23.5 [c.strings] <cuchar> macros No 4
2269(i) New 24.2.2 [container.requirements.general] Container iterators and argument-dependent lookup No 4
1213(i) Open 25.3 [iterator.requirements] Meaning of valid and singular iterator underspecified No 4
4055(i) New 25.4.3 [iterator.operations] §[iterator.operations] std::distance is missing a precondition Yes 4
2858(i) New 25.5.1 [reverse.iterators] LWG 2472: actually an incompatibility with C++03 Yes 4
3107(i) New 25.6.4 [istreambuf.iterator] istreambuf_iterator has public exposition-only member Yes 4
3729(i) New 26.2 [ranges.syn] std::tuple_element_t<std::ranges::subrange<I, S, K>> should remove top-level cv-qualifiers Yes 4
3896(i) New 26.4.5 [range.refinements] The definition of viewable_range is not quite right Yes 4
3722(i) New [range.utility.conv.to] ranges::to reserves the wrong size Yes 4
3845(i) New [range.utility.conv.to] ranges::to's from_range_t tag branch has the wrong constraint Yes 4
3994(i) New 26.7.2 [range.adaptor.object] adaptor(args...)(r) is not equivalent to std::bind_back(adaptor, args...)(r) No 4
3855(i) New [range.lazy.split.view] tiny-range is not quite right Yes 4
3864(i) New 26.7.25 [range.zip] zip over range of reference to an abstract type No 4
2173(i) Open 27 [algorithms] The meaning of operator + in the description of the algorithms Yes 4
3868(i) LEWG 27.7.5 [alg.replace] Constrained algorithms should not require output_iterator Yes 4
3933(i) New 28.4.3 [complex] P1467R9 accidentally changed the signatures of certain constructors of std::complex Yes 4
4052(i) New [rand.dist.samp.pconst] Bogus requirements for piecewise_linear_distribution No 4
3964(i) New [valarray.transcend] std::atan2 and std::pow overloads that take two std::valarray parameters should require the arguments to have the same length Yes 4
2423(i) New 28.6.5 [template.slice.array] Missing specification slice_array, gslice_array, mask_array, indirect_array copy constructor Yes 4
2115(i) Open 28.6.8 [template.mask.array] Undefined behaviour for valarray assignments with mask_array index? No 4
2923(i) New 28.7.1 [cmath.syn] noexcept is inconsistently applied across headers which import components of the C standard library No 4
2592(i) New 29.2 [time.syn] Require that chrono::duration_casts from smaller durations to larger durations do not overflow Yes 4
3678(i) New [time.zone.overview] Constructors of std::chrono::time_zone might be overly unspecified No 4
3214(i) New [facet.num.get.virtuals] §[facet.num.get.virtuals] doesn't say what it means for digit grouping to be consistent No 4
2512(i) Open [locale.time.get.virtuals] Y2K bites; what is an "unambiguous year identifier"? No 4
3910(i) New 31.4.2 [iostream.objects.overview] The effects of including <iostream> on initialization are not yet precisely specified Yes 4
3675(i) New [ios.base.storage] std::ios_base::iword/pword might be misspecified Yes 4
2214(i) Open [basic.ios.cons] Clarify basic_ios::init call restrictions Yes 4
2342(i) New [ostream] User conversion to wchar_t const* or to wchar_t not invoked for operator<< Yes 4
2286(i) Open [stringbuf.virtuals] stringbuf::underflow() underspecified Yes 4
523(i) Open 32 [re] regex case-insensitive character ranges are unimplementable as specified No 4
3835(i) New 32.1 [re.general] Requirements for CharT in the regex library No 4
3630(i) New 32.7.2 [re.regex.construct] Inconsistent basic_regex construction and assignment from iterator range No 4
2546(i) New 32.12 [re.grammar] Implementability of locale-sensitive UnicodeEscapeSequence matching No 4
2986(i) New 32.12 [re.grammar] Handling of multi-character collating elements by the regex FSM is underspecified No 4
2265(i) Open 33.5.4 [atomics.order] 29.3p9 appears to rule out some acceptable executions No 4
3999(i) New 33.5.4 [atomics.order] P0439R0 changed the value category of memory order constants Yes 4
3268(i) New 33.5.4 [atomics.order] memory_order::memory_order_foo broken in C++20 Yes 4
2095(i) LEWG 33.10.6 [futures.promise] promise and packaged_task missing constructors needed for uses-allocator construction Yes 4
2202(i) Deferred 33.10.9 [futures.async] Missing allocator support by async No 4
2478(i) New 99 [depr.conversions.string] Unclear how wstring_convert uses cvtstate No 4
2479(i) New 99 [depr.conversions.buffer] Unclear how wbuffer_convert uses cvtstate No 4
2480(i) New 99 [depr.conversions.buffer] Error handling of wbuffer_convert unclear No 4
3095(i) New 99 [depr.strstreambuf.virtuals] strstreambuf refers to nonexistent member of fpos, fpos::offset Yes 4
2481(i) New 99 [depr.conversions.string] wstring_convert should be more precise regarding "byte-error string" etc. No 4
3109(i) New 99 [depr.strstreambuf] strstreambuf is copyable No 4

Not Prioritized (72 issues)

Issue Status Section Title Proposed Resolution Priority Duplicates
4049(i) New 16.4.2 [organization] C <foo.h> headers not in freestanding Yes
4075(i) New 16.4.4 [utility.requirements] Thread stability requirement on constructors and destructors No
4033(i) New [macro.names] §[macro.names] defining macros after importing the standard library Yes
4068(i) New [res.on.requirements] Terminology for objects whose types model a concept No
4100(i) New [global.functions] Default arguments and signatures of standard library non-member functions Yes
4051(i) New 17.11.2 [cmp.categories] A less hacky and more useful way to compare comparison category types Yes
3454(i) LEWG 20.2.3 [pointer.traits] pointer_traits::pointer_to should be constexpr Yes
4058(i) New 20.2.4 [pointer.conversion] std::to_address() should be SFINAE-friendly Yes
4110(i) New [util.smartptr.shared.const] shared_ptr(nullptr_t, Deleter) is overconstrained, breaking some sensible deleters Yes
2922(i) LEWG 21.3.3 [meta.type.synop] The *_constant<> templates do not make use of template<auto> No
3967(i) New [meta.unary.prop] The specification for std::is_nothrow_* traits may be ambiguous in some cases involving noexcept(false) No
3486(i) LEWG [meta.unary.prop] is_constructible<T[], T...> may be misleading in C++20 No
4028(i) New 21.3.7 [meta.rel] std::is_(nothrow_)convertible should be reworded to avoid dependence on the return statement Yes
532(i) LEWG 22.4.9 [tuple.rel] Tuple comparison Yes 348
4072(i) New 22.5.8 [optional.comp.with.t] std::optional comparisons: constrain harder Yes
2991(i) LEWG [variant.ctor] variant copy constructor missing noexcept(see below) Yes
4078(i) New 22.14.5 [format.functions] What if arguments alias the output buffer in std::format_to? No
4107(i) New [format.range.fmtmap] Map formatter may conflict with user-defined specializations of pair/tuple formatters Yes
4106(i) New [format.args] basic_format_args should not be default-constructible Yes
2883(i) LEWG 23.3 [string.view] The standard library should provide string_view parameters instead or in addition for functions defined with char const * or string const & as parameter types. No
4102(i) New [string.view.cons] string_view(Iter, Iter) constructor breaks existing code No
4064(i) New 23.5.3 [cstring.syn] Clarify that std::launder is not needed when using the result of std::memcpy Yes
2885(i) LEWG 24 [containers] The relational operators of optional and variant completely reflect the semantics of the element types — this is inconsistent with other types in the library No
2884(i) LEWG 24 [containers] Relational operators for containers should sfinae; if the underlying type is not comparable, neither should the container be No
3976(i) New [container.alloc.reqmts] What does it mean for a type to be "allocator aware"? No
3959(i) New 24.6.9 [flat.map] Should the comparator of std::flat_map/std::flat_multimap be copied twice in some operations? No
4020(i) New [mdspan.extents.expo] extents::index-cast weirdness Yes
4021(i) New [mdspan.mdspan.overview] mdspan::is_always_meow() should be noexcept Yes
4080(i) New 25.3.2 [iterator.assoc.types] Presumed value and difference types of an iterator type in ranges and non-ranges algorithms No
4104(i) New 25.5.3 [const.iterators] basic_const_iterator<volatile int*> is not a contiguous_iterator No
4092(i) New [common.iterator] The monotonic version of common_iterator::operator== is underconstrained Yes
4062(i) New 26.3.12 [range.prim.empty] ranges::empty has no semantic requirements for forward_ranges No
4066(i) New [range.utility.conv.to] ranges::to should reserve when sized_sentinel_for is satisfied Yes
4096(i) New [range.iota.overview] views::iota(views::iota(0)) should be rejected Yes
4099(i) New [range.as.rvalue.overview] The simple case of views::as_rvalue and views::common are not strictly correct Yes
4050(i) New [range.take.overview] Should views::iota(0) | views::take(5) be views::iota(0, 5)? Yes
4009(i) New [range.drop.view] drop_view::begin const may have 𝒪(n) complexity Yes
4059(i) New [range.join.with.iterator] Leaky abstraction in join_with_view's iterator No
4108(i) New [range.lazy.split.view] lazy_split_view should be sized_range when pattern is empty tiny-range Yes
4091(i) New [range.concat.view] concat_view rejects non-movable references Yes
4073(i) New [range.concat.view] concat_view::size may overflow No
4089(i) New [range.concat.iterator] concat_view::iterator's iter_swap is overconstrained Yes
4081(i) New [range.concat.iterator] concat_view::iterator::operator- is overconstrained Yes
4097(i) New [range.reverse.overview] views::reverse should be specialized for some view types Yes
4098(i) New [range.adjacent.overview] views::adjacent<0> should reject non-forward ranges Yes
4057(i) New 26.8.6 [coro.generator.iterator] generator::iterator's operator* is not noexcept when it can be No
4095(i) New 27.4 [algorithm.syn] ranges::fold_meow should explicitly spell out the return type Yes
4105(i) New 27.6.17 [alg.ends.with] ranges::ends_with's Returns misses difference casting Yes
4093(i) New 27.6.18 [alg.fold] ranges::fold_left_first_with_iter incorrectly constructs optional<U> Yes
4094(i) New 27.6.18 [alg.fold] ranges::fold_meow is overconstrained Yes
4103(i) New 27.7.9 [alg.unique] ranges::unique_copy's constraints for the case where result is an input_iterator are not quite right Yes
2985(i) LEWG 27.7.10 [alg.reverse] std::reverse should be permitted to be vectorized Yes
2973(i) LEWG 27.8.6 [alg.merge] inplace_merge exact comparison count complexity prohibits useful real-world optimizations Yes
4034(i) New 27.8.9 [alg.min.max] Clarify specification of std::min and std::max Yes
4077(i) New 27.12.2 [alg.rand.generate] Unclear preconditions of std::ranges::generate_random No
4086(i) New 27.12.2 [alg.rand.generate] ranges::generate_random_n is missing Yes
4085(i) New 27.12.2 [alg.rand.generate] ranges::generate_random's helper lambda should specify the return type Yes
4109(i) New [rand.req.genl] Instantiating templates in §[rand] with int8_t/uint8_t is undefined behavior Yes
4067(i) New [time.zone.zonedtime.ctor] Inconsistency and potential infinity meta-recursion in std::chrono::zoned_time's constructors Yes
4022(i) New 29.12 [time.format] Ambiguity in the formatting of negative years with format specifier %C Yes
4039(i) New [ostream.formatted.print] §[ostream.formatted.print]: Inappropriate usage of badbit in definition of vprint_unicode/vprint_nonunicode Yes
4088(i) New [ostream.formatted.print] println ignores the locale imbued in std::ostream Yes
3992(i) New [stringbuf.members] basic_stringbuf::str()&& should enforce 𝒪(1) Yes
1484(i) LEWG 33.4.3 [thread.thread.class] Need a way to join a thread with a timeout No
2236(i) SG1 33.5.2 [atomics.syn] kill_dependency unconditionally noexcept No
1459(i) LEWG 33.5.4 [atomics.order] Overlapping evaluations are allowed No 1458
1488(i) LEWG 33.6 [thread.mutex] Improve interoperability between the C++0x and C1x threads APIs No
1493(i) LEWG 33.6.4 [thread.mutex.requirements] Add mutex, recursive_mutex, is_locked function No
936(i) LEWG 33.6.4 [thread.mutex.requirements] Mutex type overspecified No 961
961(i) LEWG 33.6.4 [thread.mutex.requirements] Various threading bugs #11 No 936
2533(i) SG1 99 [concurr.ts::futures.unique.future] [concurr.ts] Constrain threads where future::then can run a continuation No
3114(i) LEWG 16 [networking.ts::buffer] [networking.ts] Permit efficient composition when using DynamicBuffer Yes