libc++ C++17 Status

Overview

In November 2014, the C++ standard committee created a draft for the next version of the C++ standard, initially known as “C++1z”. In February 2017, the C++ standard committee approved this draft, and sent it to ISO for approval as C++17.

This page shows the status of libc++; the status of clang’s support of the language features is here.

The groups that have contributed papers:

• CWG - Core Language Working group

• LWG - Library working group

• SG1 - Study group #1 (Concurrency working group)

Note

“Nothing to do” means that no library changes were needed to implement this change.

Paper Status

Paper #	Paper Name	Meeting	Status	First released version	Notes
N3911	TransformationTrait Alias void_t.	2014-11 (Urbana)	Complete	3.6
N4089	Safe conversions in unique_ptr<T[]>.	2014-11 (Urbana)	In Progress	3.9
N4169	A proposal to add invoke function template	2014-11 (Urbana)	Complete	3.7
N4190	Removing auto_ptr, random_shuffle(), And Old <functional> Stuff.	2014-11 (Urbana)	Complete	15
N4258	Cleaning-up noexcept in the Library.	2014-11 (Urbana)	In Progress	3.7
N4259	Wording for std::uncaught_exceptions	2014-11 (Urbana)	Complete	3.7	std::uncaught_exception is deprecated since LLVM 20
N4277	TriviallyCopyable reference_wrapper.	2014-11 (Urbana)	Complete	3.2
N4279	Improved insertion interface for unique-key maps.	2014-11 (Urbana)	Complete	3.7
N4280	Non-member size() and more	2014-11 (Urbana)	Complete	3.6
N4284	Contiguous Iterators.	2014-11 (Urbana)	Complete	3.6
N4285	Cleanup for exception-specification and throw-expression.	2014-11 (Urbana)	Complete	4
N4387	improving pair and tuple	2015-05 (Lenexa)	Complete	4
N4389	bool_constant	2015-05 (Lenexa)	Complete	3.7
N4508	shared_mutex for C++17	2015-05 (Lenexa)	Complete	3.7
N4366	LWG 2228 missing SFINAE rule	2015-05 (Lenexa)	Complete	3.1
N4510	Minimal incomplete type support for standard containers, revision 4	2015-05 (Lenexa)	Complete	3.6
P0004R1	Remove Deprecated iostreams aliases.	2015-10 (Kona)	Complete	3.8
P0006R0	Adopt Type Traits Variable Templates for C++17.	2015-10 (Kona)	Complete	3.8
P0092R1	Polishing <chrono>	2015-10 (Kona)	Complete	3.8
P0007R1	Constant View: A proposal for a std::as_const helper function template.	2015-10 (Kona)	Complete	3.8
P0156R0	Variadic lock_guard(rev 3).	2015-10 (Kona)	Nothing To Do		Pulled at the 2017-01 meeting in Kona
P0074R0	Making std::owner_less more flexible	2015-10 (Kona)	Complete	3.8
P0013R1	Logical type traits rev 2	2015-10 (Kona)	Complete	3.8
P0024R2	The Parallelism TS Should be Standardized	2016-02 (Jacksonville)	Partial
P0226R1	Mathematical Special Functions for C++17	2016-02 (Jacksonville)	In Progress		Progress is tracked here
P0220R1	Adopt Library Fundamentals V1 TS Components for C++17	2016-02 (Jacksonville)	Complete	16
P0218R1	Adopt the File System TS for C++17	2016-02 (Jacksonville)	Complete	7
P0033R1	Re-enabling shared_from_this	2016-02 (Jacksonville)	Complete	3.9
P0005R4	Adopt not_fn from Library Fundamentals 2 for C++17	2016-02 (Jacksonville)	Complete	3.9
P0152R1	constexpr atomic::is_always_lock_free	2016-02 (Jacksonville)	Complete	3.9
P0185R1	Adding [nothrow-]swappable traits	2016-02 (Jacksonville)	Complete	3.9
P0253R1	Fixing a design mistake in the searchers interface	2016-02 (Jacksonville)	Complete	3.9
P0025R0	An algorithm to “clamp” a value between a pair of boundary values	2016-02 (Jacksonville)	Complete	3.9
P0154R1	constexpr std::hardware_{constructive,destructive}_interference_size	2016-02 (Jacksonville)	Complete	19	The required macros are only implemented as of LLVM 19.
P0030R1	Proposal to Introduce a 3-Argument Overload to std::hypot	2016-02 (Jacksonville)	Complete	3.9
P0031R0	A Proposal to Add Constexpr Modifiers to reverse_iterator, move_iterator, array and Range Access	2016-02 (Jacksonville)	Complete	4
P0272R1	Give std::string a non-const .data() member function	2016-02 (Jacksonville)	Complete	3.9
P0077R2	is_callable, the missing INVOKE related trait	2016-02 (Jacksonville)	Complete	3.9
P0032R3	Homogeneous interface for variant, any and optional	2016-06 (Oulu)	Complete	4
P0040R3	Extending memory management tools	2016-06 (Oulu)	Complete	4
P0063R3	C++17 should refer to C11 instead of C99	2016-06 (Oulu)	Complete	7
P0067R3	Elementary string conversions	2016-06 (Oulu)	Nothing To Do	n/a	Resolved by P0067R5
P0083R3	Splicing Maps and Sets	2016-06 (Oulu)	Complete	8
P0084R2	Emplace Return Type	2016-06 (Oulu)	Complete	4
P0088R3	Variant: a type-safe union for C++17	2016-06 (Oulu)	Complete	4
P0137R1	Core Issue 1776: Replacement of class objects containing reference members	2016-06 (Oulu)	Complete	6
P0163R0	shared_ptr::weak_type	2016-06 (Oulu)	Complete	3.9
P0174R2	Deprecating Vestigial Library Parts in C++17	2016-06 (Oulu)	Complete	15
P0175R1	Synopses for the C library	2016-06 (Oulu)
P0180R2	Reserve a New Library Namespace for Future Standardization	2016-06 (Oulu)	Nothing To Do	n/a
P0181R1	Ordered by Default	2016-06 (Oulu)	Nothing To Do	n/a	Pulled at the 2017-01 meeting in Kona
P0209R2	make_from_tuple: apply for construction	2016-06 (Oulu)	Complete	3.9
P0219R1	Relative Paths for Filesystem	2016-06 (Oulu)	Complete	7
P0254R2	Integrating std::string_view and std::string	2016-06 (Oulu)	Complete	4
P0258R2	has_unique_object_representations	2016-06 (Oulu)	Complete	6
P0295R0	Adopt Selected Library Fundamentals V2 Components for C++17	2016-06 (Oulu)	Complete	4
P0302R1	Removing Allocator Support in std::function	2016-06 (Oulu)	Complete	4
P0307R2	Making Optional Greater Equal Again	2016-06 (Oulu)	Complete	4
P0336R1	Better Names for Parallel Execution Policies in C++17	2016-06 (Oulu)	Complete	17
P0337R0	Delete operator= for polymorphic_allocator	2016-06 (Oulu)	Complete	3.9
P0346R1	A <random> Nomenclature Tweak	2016-06 (Oulu)	Complete	3.9
P0358R1	Fixes for not_fn	2016-06 (Oulu)	Complete	3.9
P0371R1	Temporarily discourage memory_order_consume	2016-06 (Oulu)	Nothing To Do	n/a
P0392R0	Adapting string_view by filesystem paths	2016-06 (Oulu)	Complete	4
P0393R3	Making Variant Greater Equal	2016-06 (Oulu)	Complete	4
P0394R4	Hotel Parallelifornia: terminate() for Parallel Algorithms Exception Handling	2016-06 (Oulu)	Complete	17
P0003R5	Removing Deprecated Exception Specifications from C++17	2016-11 (Issaquah)	Complete	5
P0067R5	Elementary string conversions, revision 5	2016-11 (Issaquah)	Partial		For integer types, std::(to|from)_chars has been available since v7; for float and double, std::to_chars since v14 and std::from_chars since v20. Support is complete except for long double.
P0403R1	Literal suffixes for basic_string_view	2016-11 (Issaquah)	Complete	4
P0414R2	Merging shared_ptr changes from Library Fundamentals to C++17	2016-11 (Issaquah)	Complete	11
P0418R2	Fail or succeed: there is no atomic lattice	2016-11 (Issaquah)
P0426R1	Constexpr for std::char_traits	2016-11 (Issaquah)	Complete	4
P0435R1	Resolving LWG Issues re common_type	2016-11 (Issaquah)	Complete	4
P0502R0	Throwing out of a parallel algorithm terminates - but how?	2016-11 (Issaquah)
P0503R0	Correcting library usage of “literal type”	2016-11 (Issaquah)	Complete	4
P0504R0	Revisiting in-place tag types for any/optional/variant	2016-11 (Issaquah)	Complete	4
P0505R0	Wording for GB 50 - constexpr for chrono	2016-11 (Issaquah)	Complete	4
P0508R0	Wording for GB 58 - structured bindings for node_handles	2016-11 (Issaquah)	Complete	7
P0509R1	Updating “Restrictions on exception handling”	2016-11 (Issaquah)	Nothing To Do	n/a
P0510R0	Disallowing references, incomplete types, arrays, and empty variants	2016-11 (Issaquah)	Complete	4
P0513R0	Poisoning the Hash	2016-11 (Issaquah)	Complete	5
P0516R0	Clarify That shared_future’s Copy Operations have Wide Contracts	2016-11 (Issaquah)	Complete	4
P0517R0	Make future_error Constructible	2016-11 (Issaquah)	Complete	4
P0521R0	Proposed Resolution for CA 14 (shared_ptr use_count/unique)	2016-11 (Issaquah)	Complete	18
P0156R2	Variadic Lock guard(rev 5)	2017-02 (Kona)	Complete	5
P0270R3	Removing C dependencies from signal handler wording	2017-02 (Kona)
P0298R3	A byte type definition	2017-02 (Kona)	Complete	5
P0317R1	Directory Entry Caching for Filesystem	2017-02 (Kona)	Complete	7
P0430R2	File system library on non-POSIX-like operating systems	2017-02 (Kona)	Complete	7
P0433R2	Toward a resolution of US7 and US14: Integrating template deduction for class templates into the standard library	2017-02 (Kona)	Complete	14
P0452R1	Unifying <numeric> Parallel Algorithms	2017-02 (Kona)	Partial		The changes to std::transform_inclusive_scan and std::transform_exclusive_scan have not yet been implemented.
P0467R2	Iterator Concerns for Parallel Algorithms	2017-02 (Kona)	Partial
P0492R2	Proposed Resolution of C++17 National Body Comments for Filesystems	2017-02 (Kona)	Complete	7
P0518R1	Allowing copies as arguments to function objects given to parallel algorithms in response to CH11	2017-02 (Kona)	Nothing To Do
P0523R1	Wording for CH 10: Complexity of parallel algorithms	2017-02 (Kona)	Nothing To Do
P0548R1	common_type and duration	2017-02 (Kona)	Complete	5
P0558R1	Resolving atomic<T> named base class inconsistencies	2017-02 (Kona)	Complete
P0574R1	Algorithm Complexity Constraints and Parallel Overloads	2017-02 (Kona)	Nothing To Do
P0599R1	noexcept for hash functions	2017-02 (Kona)	Complete	5
P0604R0	Resolving GB 55, US 84, US 85, US 86	2017-02 (Kona)	Complete
P0607R0	Inline Variables for the Standard Library	2017-02 (Kona)	In Progress	6	The parts of P0607 that are not done are the <regex> bits
P0618R0	Deprecating <codecvt>	2017-02 (Kona)	Complete	15
P0623R0	Final C++17 Parallel Algorithms Fixes	2017-02 (Kona)	Nothing To Do
P0682R1	Repairing elementary string conversions	2017-07 (Toronto)
P0739R0	Some improvements to class template argument deduction integration into the standard library	2017-07 (Toronto)	Complete	5

Library Working Group Issues Status

Issue #	Issue Name	Meeting	Status	First released version	Notes
LWG2016	Allocators must be no-throw swappable	2014-11 (Urbana)	Complete
LWG2118	unique_ptr for array does not support cv qualification conversion of actual argument	2014-11 (Urbana)	Complete
LWG2170	Aggregates cannot be DefaultConstructible	2014-11 (Urbana)	Complete
LWG2340	Replacement allocation functions declared as inline	2014-11 (Urbana)	Complete
LWG2354	Unnecessary copying when inserting into maps with braced-init syntax	2014-11 (Urbana)	Complete
LWG2377	std::align requirements overly strict	2014-11 (Urbana)	Complete
LWG2396	underlying_type doesn’t say what to do for an incomplete enumeration type	2014-11 (Urbana)	Complete
LWG2399	shared_ptr‘s constructor from unique_ptr should be constrained	2014-11 (Urbana)	Complete
LWG2400	shared_ptr‘s get_deleter() should use addressof()	2014-11 (Urbana)	Complete
LWG2401	std::function needs more noexcept	2014-11 (Urbana)	Complete
LWG2404	mismatch()‘s complexity needs to be updated	2014-11 (Urbana)	Complete
LWG2408	SFINAE-friendly common_type / iterator_traits is missing in C++14	2014-11 (Urbana)	Complete
LWG2106	move_iterator wrapping iterators returning prvalues	2014-11 (Urbana)	Complete
LWG2129	User specializations of std::initializer_list	2014-11 (Urbana)	Complete
LWG2212	tuple_size for const pair request <tuple> header	2014-11 (Urbana)	Complete
LWG2217	operator==(sub_match, string) slices on embedded ‘0’s	2014-11 (Urbana)	Complete
LWG2230	“see below” for initializer_list constructors of unordered containers	2014-11 (Urbana)	Complete
LWG2233	bad_function_call::what() unhelpful	2014-11 (Urbana)	Complete
LWG2266	vector and deque have incorrect insert requirements	2014-11 (Urbana)	Complete
LWG2325	minmax_element()‘s behavior differing from max_element()‘s should be noted	2014-11 (Urbana)	Complete
LWG2361	Apply 2299 resolution throughout library	2014-11 (Urbana)	Complete
LWG2365	Missing noexcept in shared_ptr::shared_ptr(nullptr_t)	2014-11 (Urbana)	Complete
LWG2376	bad_weak_ptr::what() overspecified	2014-11 (Urbana)	Complete
LWG2387	More nested types that must be accessible and unambiguous	2014-11 (Urbana)	Complete
LWG2059	C++0x ambiguity problem with map::erase	2015-05 (Lenexa)	Complete
LWG2063	Contradictory requirements for string move assignment	2015-05 (Lenexa)	Complete
LWG2076	Bad CopyConstructible requirement in set constructors	2015-05 (Lenexa)	Complete
LWG2160	Unintended destruction ordering-specification of resize	2015-05 (Lenexa)	Complete
LWG2168	Inconsistent specification of uniform_real_distribution constructor	2015-05 (Lenexa)	Complete
LWG2239	min/max/minmax requirements	2015-05 (Lenexa)	Complete
LWG2364	deque and vector pop_back don’t specify iterator invalidation requirements	2015-05 (Lenexa)	Complete
LWG2369	constexpr max(initializer_list) vs max_element	2015-05 (Lenexa)	Complete
LWG2378	Behaviour of standard exception types	2015-05 (Lenexa)	Complete
LWG2403	stof() should call strtof() and wcstof()	2015-05 (Lenexa)	Complete
LWG2406	negative_binomial_distribution should reject p == 1	2015-05 (Lenexa)	Complete
LWG2407	packaged_task(allocator_arg_t, const Allocator&, F&&) should neither be constrained nor explicit	2015-05 (Lenexa)	Complete
LWG2411	shared_ptr is only contextually convertible to bool	2015-05 (Lenexa)	Complete
LWG2415	Inconsistency between unique_ptr and shared_ptr	2015-05 (Lenexa)	Complete
LWG2420	function<void(ArgTypes…)> does not discard the return value of the target object	2015-05 (Lenexa)	Complete
LWG2425	operator delete(void*, size_t) doesn’t invalidate pointers sufficiently	2015-05 (Lenexa)	Complete
LWG2427	Container adaptors as sequence containers, redux	2015-05 (Lenexa)	Complete
LWG2428	“External declaration” used without being defined	2015-05 (Lenexa)	Complete
LWG2433	uninitialized_copy()/etc. should tolerate overloaded operator&	2015-05 (Lenexa)	Complete
LWG2434	shared_ptr::use_count() is efficient	2015-05 (Lenexa)	Complete
LWG2437	iterator_traits::reference can and can’t be void	2015-05 (Lenexa)	Complete
LWG2438	std::iterator inheritance shouldn’t be mandated	2015-05 (Lenexa)	Complete
LWG2439	unique_copy() sometimes can’t fall back to reading its output	2015-05 (Lenexa)	Complete
LWG2440	seed_seq::size() should be noexcept	2015-05 (Lenexa)	Complete
LWG2442	call_once() shouldn’t DECAY_COPY()	2015-05 (Lenexa)	Complete
LWG2448	Non-normative Container destructor specification	2015-05 (Lenexa)	Complete
LWG2454	Add raw_storage_iterator::base() member	2015-05 (Lenexa)	Complete
LWG2455	Allocator default construction should be allowed to throw	2015-05 (Lenexa)	Complete
LWG2458	N3778 and new library deallocation signatures	2015-05 (Lenexa)	Complete
LWG2459	std::polar should require a non-negative rho	2015-05 (Lenexa)	Complete
LWG2464	try_emplace and insert_or_assign misspecified	2015-05 (Lenexa)	Complete
LWG2467	is_always_equal has slightly inconsistent default	2015-05 (Lenexa)	Complete
LWG2470	Allocator’s destroy function should be allowed to fail to instantiate	2015-05 (Lenexa)	Complete
LWG2482	[c.strings] Table 73 mentions nonexistent functions	2015-05 (Lenexa)	Complete
LWG2488	Placeholders should be allowed and encouraged to be constexpr	2015-05 (Lenexa)	Complete
LWG1169	num_get not fully compatible with strto*	2015-10 (Kona)	Complete
LWG2072	Unclear wording about capacity of temporary buffers	2015-10 (Kona)	Complete
LWG2101	Some transformation types can produce impossible types	2015-10 (Kona)	Complete
LWG2111	Which unexpected&#47;``terminate`` handler is called from the exception handling runtime?	2015-10 (Kona)	Complete
LWG2119	Missing hash specializations for extended integer types	2015-10 (Kona)	Complete
LWG2127	Move-construction with raw_storage_iterator	2015-10 (Kona)	Complete
LWG2133	Attitude to overloaded comma for iterators	2015-10 (Kona)	Complete
LWG2156	Unordered containers’ reserve(n) reserves for n-1 elements	2015-10 (Kona)	Complete
LWG2218	Unclear how containers use allocator_traits::construct()	2015-10 (Kona)	Complete
LWG2219	*INVOKE*-ing a pointer to member with a reference_wrapper as the object expression	2015-10 (Kona)	Complete
LWG2224	Ambiguous status of access to non-live objects	2015-10 (Kona)	Complete
LWG2234	assert() should allow usage in constant expressions	2015-10 (Kona)	Complete
LWG2244	Issue on basic_istream::seekg	2015-10 (Kona)	Complete
LWG2250	Follow-up On Library Issue 2207	2015-10 (Kona)	Complete
LWG2259	Issues in 17.6.5.5 rules for member functions	2015-10 (Kona)	Complete
LWG2273	regex_match ambiguity	2015-10 (Kona)	Complete
LWG2336	is_trivially_constructible/is_trivially_assignable traits are always false	2015-10 (Kona)	Complete
LWG2353	std::next is over-constrained	2015-10 (Kona)	Complete
LWG2367	pair and tuple are not correctly implemented for is_constructible with no args	2015-10 (Kona)	Complete
LWG2380	May <cstdlib> provide long ::abs(long) and long long ::abs(long long)?	2015-10 (Kona)	Complete
LWG2384	Allocator’s deallocate function needs better specification	2015-10 (Kona)	Complete
LWG2385	function::assign allocator argument doesn’t make sense	2015-10 (Kona)	Complete
LWG2435	reference_wrapper::operator()‘s Remark should be deleted	2015-10 (Kona)	Complete
LWG2447	Allocators and volatile-qualified value types	2015-10 (Kona)	Complete
LWG2462	std::ios_base::failure is overspecified	2015-10 (Kona)	Complete
LWG2466	allocator_traits::max_size() default behavior is incorrect	2015-10 (Kona)	Complete
LWG2469	Wrong specification of Requires clause of operator[] for map and unordered_map	2015-10 (Kona)	Complete
LWG2473	basic_filebuf‘s relation to C FILE semantics	2015-10 (Kona)	Complete
LWG2476	scoped_allocator_adaptor is not assignable	2015-10 (Kona)	Complete
LWG2477	Inconsistency of wordings in std::vector::erase() and std::deque::erase()	2015-10 (Kona)	Complete
LWG2483	throw_with_nested() should use is_final	2015-10 (Kona)	Complete
LWG2484	rethrow_if_nested() is doubly unimplementable	2015-10 (Kona)	Complete
LWG2485	get() should be overloaded for const tuple&&	2015-10 (Kona)	Complete
LWG2486	mem_fn() should be required to use perfect forwarding	2015-10 (Kona)	Complete
LWG2487	bind() should be const-overloaded, not cv-overloaded	2015-10 (Kona)	Complete
LWG2489	mem_fn() should be noexcept	2015-10 (Kona)	Complete
LWG2492	Clarify requirements for comp	2015-10 (Kona)	Complete
LWG2495	There is no such thing as an Exception Safety element	2015-10 (Kona)	Complete
LWG2192	Validity and return type of std::abs(0u) is unclear	2016-02 (Jacksonville)	Complete
LWG2276	Missing requirement on std::promise::set_exception	2016-02 (Jacksonville)	Complete
LWG2296	std::addressof should be constexpr	2016-02 (Jacksonville)	Complete
LWG2450	(greater|less|greater_equal|less_equal)<void> do not yield a total order for pointers	2016-02 (Jacksonville)	Complete
LWG2520	N4089 broke initializing unique_ptr<T[]> from a nullptr	2016-02 (Jacksonville)	Complete
LWG2522	[fund.ts.v2] Contradiction in set_default_resource specification	2016-02 (Jacksonville)	Complete
LWG2523	std::promise synopsis shows two set_value_at_thread_exit()‘s for no apparent reason	2016-02 (Jacksonville)	Complete
LWG2537	Constructors for priority_queue taking allocators should call make_heap	2016-02 (Jacksonville)	Complete
LWG2539	[fund.ts.v2] invocation_trait definition definition doesn’t work for surrogate call functions	2016-02 (Jacksonville)
LWG2545	Simplify wording for bind without explicitly specified return type	2016-02 (Jacksonville)	Complete
LWG2557	Logical operator traits are broken in the zero-argument case	2016-02 (Jacksonville)	Complete
LWG2558	[fund.ts.v2] Logical operator traits are broken in the zero-argument case	2016-02 (Jacksonville)	Complete
LWG2559	Error in LWG 2234’s resolution	2016-02 (Jacksonville)	Complete
LWG2560	is_constructible underspecified when applied to a function type	2016-02 (Jacksonville)	Complete
LWG2565	std::function‘s move constructor should guarantee nothrow for reference_wrappers and function pointers	2016-02 (Jacksonville)	Complete
LWG2566	Requirements on the first template parameter of container adaptors	2016-02 (Jacksonville)	Complete
LWG2571	§[map.modifiers]/2 imposes nonsensical requirement on insert(InputIterator, InputIterator)	2016-02 (Jacksonville)	Complete
LWG2572	The remarks for shared_ptr::operator* should apply to cv-qualified void as well	2016-02 (Jacksonville)	Complete
LWG2574	[fund.ts.v2] std::experimental::function::operator=(F&&) should be constrained	2016-02 (Jacksonville)	Complete
LWG2575	[fund.ts.v2] experimental::function::assign should be removed	2016-02 (Jacksonville)
LWG2576	istream_iterator and ostream_iterator should use std::addressof	2016-02 (Jacksonville)	Complete
LWG2577	{shared,unique}_lock should use std::addressof	2016-02 (Jacksonville)	Complete
LWG2579	Inconsistency wrt Allocators in basic_string assignment vs. basic_string::assign	2016-02 (Jacksonville)	Complete
LWG2581	Specialization of <type_traits> variable templates should be prohibited	2016-02 (Jacksonville)	Complete
LWG2582	§[res.on.functions]/2’s prohibition against incomplete types shouldn’t apply to type traits	2016-02 (Jacksonville)	Complete
LWG2583	There is no way to supply an allocator for basic_string(str, pos)	2016-02 (Jacksonville)	Complete
LWG2585	forward_list::resize(size_type, const value_type&) effects incorrect	2016-02 (Jacksonville)	Complete
LWG2586	Wrong value category used in scoped_allocator_adaptor::construct()	2016-02 (Jacksonville)	Complete
LWG2590	Aggregate initialization for std::array	2016-02 (Jacksonville)	Complete
LWG2181	Exceptions from seed sequence operations	2016-06 (Oulu)	Complete
LWG2309	mutex::lock() should not throw device_or_resource_busy	2016-06 (Oulu)	Complete
LWG2310	Public exposition only member in std::array	2016-06 (Oulu)	Complete
LWG2312	tuple’s constructor constraints need to be phrased more precisely	2016-06 (Oulu)	Complete
LWG2328	Rvalue stream extraction should use perfect forwarding	2016-06 (Oulu)	Complete
LWG2393	std::function’s Callable definition is broken	2016-06 (Oulu)	Complete
LWG2422	std::numeric_limits<T>::is_modulo description: “most machines” errata	2016-06 (Oulu)	Complete
LWG2426	Issue about compare_exchange	2016-06 (Oulu)	Complete
LWG2436	Comparators for associative containers should always be CopyConstructible	2016-06 (Oulu)	Complete
LWG2441	Exact-width atomic typedefs should be provided	2016-06 (Oulu)	Complete
LWG2451	[fund.ts.v2] optional should ‘forward’ T’s implicit conversions	2016-06 (Oulu)	Nothing To Do
LWG2509	[fund.ts.v2] any_cast doesn’t work with rvalue reference targets and cannot move with a value target	2016-06 (Oulu)	Complete
LWG2516	[fund.ts.v2] Public “exposition only” members in observer_ptr	2016-06 (Oulu)	Complete	18
LWG2542	Missing const requirements for associative containers	2016-06 (Oulu)
LWG2549	Tuple EXPLICIT constructor templates that take tuple parameters end up taking references to temporaries and will create dangling references	2016-06 (Oulu)	Complete
LWG2550	Wording of unordered container’s clear() method complexity	2016-06 (Oulu)	Complete
LWG2551	[fund.ts.v2] “Exception safety” cleanup in library fundamentals required	2016-06 (Oulu)	Complete
LWG2555	[fund.ts.v2] No handling for over-aligned types in optional	2016-06 (Oulu)	Complete
LWG2573	[fund.ts.v2] std::hash<std::experimental::shared_ptr> does not work for arrays	2016-06 (Oulu)
LWG2596	vector::data() should use addressof	2016-06 (Oulu)	Complete
LWG2667	path::root_directory() description is confusing	2016-06 (Oulu)	Complete
LWG2669	recursive_directory_iterator effects refers to non-existent functions	2016-06 (Oulu)	Complete
LWG2670	system_complete refers to undefined variable ‘base’	2016-06 (Oulu)	Complete
LWG2671	Errors in Copy	2016-06 (Oulu)	Complete
LWG2673	status() effects cannot be implemented as specified	2016-06 (Oulu)	Complete
LWG2674	Bidirectional iterator requirement on path::iterator is very expensive	2016-06 (Oulu)	Complete
LWG2683	filesystem::copy() says “no effects”	2016-06 (Oulu)	Complete
LWG2684	priority_queue lacking comparator typedef	2016-06 (Oulu)	Complete
LWG2685	shared_ptr deleters must not throw on move construction	2016-06 (Oulu)	Complete
LWG2687	{inclusive,exclusive}_scan misspecified	2016-06 (Oulu)
LWG2688	clamp misses preconditions and has extraneous condition on result	2016-06 (Oulu)	Complete
LWG2689	Parallel versions of std::copy and std::move shouldn’t be in order	2016-06 (Oulu)	Nothing To Do
LWG2698	Effect of assign() on iterators/pointers/references	2016-06 (Oulu)	Complete
LWG2704	recursive_directory_iterator’s members should require ‘*this is dereferenceable’	2016-06 (Oulu)	Complete
LWG2706	Error reporting for recursive_directory_iterator::pop() is under-specified	2016-06 (Oulu)	Complete
LWG2707	path construction and assignment should have “string_type&&” overloads	2016-06 (Oulu)	Complete
LWG2709	offsetof is unnecessarily imprecise	2016-06 (Oulu)
LWG2710	“Effects: Equivalent to …” doesn’t count “Synchronization:” as determined semantics	2016-06 (Oulu)	Complete
LWG2711	path is convertible from approximately everything under the sun	2016-06 (Oulu)	Complete
LWG2716	Specification of shuffle and sample disallows lvalue URNGs	2016-06 (Oulu)	Complete
LWG2718	Parallelism bug in [algorithms.parallel.exec] p2	2016-06 (Oulu)
LWG2719	permissions function should not be noexcept due to narrow contract	2016-06 (Oulu)	Complete
LWG2720	permissions function incorrectly specified for symlinks	2016-06 (Oulu)	Complete
LWG2721	remove_all has incorrect post conditions	2016-06 (Oulu)	Complete
LWG2723	Do directory_iterator and recursive_directory_iterator become the end iterator upon error?	2016-06 (Oulu)	Complete
LWG2724	The protected virtual member functions of memory_resource should be private	2016-06 (Oulu)	Complete	16
LWG2725	filesystem::exists(const path&, error_code&) error reporting	2016-06 (Oulu)	Complete
LWG2726	[recursive_]directory_iterator::increment(error_code&) is underspecified	2016-06 (Oulu)	Complete
LWG2727	Parallel algorithms with constexpr specifier	2016-06 (Oulu)
LWG2728	status(p).permissions() and symlink_status(p).permissions() are not specified	2016-06 (Oulu)	Complete
LWG2062	Effect contradictions w/o no-throw guarantee of std::function swaps	2016-11 (Issaquah)	Complete
LWG2166	Heap property underspecified?	2016-11 (Issaquah)
LWG2221	No formatted output operator for nullptr	2016-11 (Issaquah)	Complete
LWG2223	shrink_to_fit effect on iterator validity	2016-11 (Issaquah)	Complete
LWG2261	Are containers required to use their ‘pointer’ type internally?	2016-11 (Issaquah)
LWG2394	locale::name specification unclear - what is implementation-defined?	2016-11 (Issaquah)	Complete
LWG2460	LWG issue 2408 and value categories	2016-11 (Issaquah)	Complete
LWG2468	Self-move-assignment of library types	2016-11 (Issaquah)
LWG2475	Allow overwriting of std::basic_string terminator with charT() to allow cleaner interoperation with legacy APIs	2016-11 (Issaquah)	Complete
LWG2503	multiline option should be added to syntax_option_type	2016-11 (Issaquah)	Complete
LWG2510	Tag types should not be DefaultConstructible	2016-11 (Issaquah)	Complete
LWG2514	Type traits must not be final	2016-11 (Issaquah)	Complete
LWG2518	[fund.ts.v2] Non-member swap for propagate_const should call member swap	2016-11 (Issaquah)	Complete
LWG2519	Iterator operator-= has gratuitous undefined behaviour	2016-11 (Issaquah)	Complete
LWG2521	[fund.ts.v2] weak_ptr’s converting move constructor should be modified as well for array support	2016-11 (Issaquah)
LWG2525	[fund.ts.v2] get_memory_resource should be const and noexcept	2016-11 (Issaquah)
LWG2527	[fund.ts.v2] ALLOCATOR_OF for function::operator= has incorrect default	2016-11 (Issaquah)
LWG2531	future::get should explicitly state that the shared state is released	2016-11 (Issaquah)	Nothing To Do
LWG2534	Constrain rvalue stream operators	2016-11 (Issaquah)	Complete
LWG2536	What should <complex.h> do?	2016-11 (Issaquah)	Complete
LWG2540	unordered_multimap::insert hint iterator	2016-11 (Issaquah)	Complete
LWG2543	LWG 2148 (hash support for enum types) seems under-specified	2016-11 (Issaquah)	Complete
LWG2544	istreambuf_iterator(basic_streambuf<charT, traits>* s) effects unclear when s is 0	2016-11 (Issaquah)	Complete
LWG2556	Wide contract for future::share()	2016-11 (Issaquah)	Complete
LWG2562	Consistent total ordering of pointers by comparison functors	2016-11 (Issaquah)
LWG2567	Specification of logical operator traits uses BaseCharacteristic, which is defined only for UnaryTypeTraits and BinaryTypeTraits	2016-11 (Issaquah)	Complete
LWG2568	[fund.ts.v2] Specification of logical operator traits uses BaseCharacteristic, which is defined only for UnaryTypeTraits and BinaryTypeTraits	2016-11 (Issaquah)	Complete	15
LWG2569	conjunction and disjunction requirements are too strict	2016-11 (Issaquah)	Complete	15
LWG2570	[fund.ts.v2] conjunction and disjunction requirements are too strict	2016-11 (Issaquah)
LWG2578	Iterator requirements should reference iterator traits	2016-11 (Issaquah)	Complete
LWG2584	<regex> ECMAScript IdentityEscape is ambiguous	2016-11 (Issaquah)
LWG2587	“Convertible to bool” requirement in conjunction and disjunction	2016-11 (Issaquah)	Nothing To Do		Resolved by LWG2567
LWG2588	[fund.ts.v2] “Convertible to bool” requirement in conjunction and disjunction	2016-11 (Issaquah)	Nothing To Do		Resolved by LWG2568
LWG2589	match_results can’t satisfy the requirements of a container	2016-11 (Issaquah)	Complete
LWG2591	std::function’s member template target() should not lead to undefined behaviour	2016-11 (Issaquah)	Complete
LWG2598	addressof works on temporaries	2016-11 (Issaquah)	Complete
LWG2664	operator/ (and other append) semantics not useful if argument has root	2016-11 (Issaquah)	Complete
LWG2665	remove_filename() post condition is incorrect	2016-11 (Issaquah)	Complete
LWG2672	Should is_empty use error_code in its specification?	2016-11 (Issaquah)	Complete
LWG2678	std::filesystem enum classes overspecified	2016-11 (Issaquah)	Complete
LWG2679	Inconsistent Use of Effects and Equivalent To	2016-11 (Issaquah)	Complete
LWG2680	Add “Equivalent to” to filesystem	2016-11 (Issaquah)	Complete
LWG2681	filesystem::copy() cannot copy symlinks	2016-11 (Issaquah)	Complete
LWG2686	Why is std::hash specialized for error_code, but not error_condition?	2016-11 (Issaquah)	Complete
LWG2694	Application of LWG 436 accidentally deleted definition of “facet”	2016-11 (Issaquah)	Complete
LWG2696	Interaction between make_shared and enable_shared_from_this is underspecified	2016-11 (Issaquah)	Nothing To Do
LWG2699	Missing restriction in [numeric.requirements]	2016-11 (Issaquah)	Complete
LWG2712	copy_file(from, to, …) has a number of unspecified error conditions	2016-11 (Issaquah)	Complete
LWG2722	equivalent incorrectly specifies throws clause	2016-11 (Issaquah)	Complete
LWG2729	Missing SFINAE on std::pair::operator=	2016-11 (Issaquah)	Complete
LWG2732	Questionable specification of path::operator/= and path::append	2016-11 (Issaquah)	Complete
LWG2733	[fund.ts.v2] gcd / lcm and bool	2016-11 (Issaquah)	Complete
LWG2735	std::abs(short), std::abs(signed char) and others should return int instead of double in order to be compatible with C++98 and C	2016-11 (Issaquah)	Complete
LWG2736	nullopt_t insufficiently constrained	2016-11 (Issaquah)	Complete
LWG2738	is_constructible with void types	2016-11 (Issaquah)	Complete
LWG2739	Issue with time_point non-member subtraction with an unsigned duration	2016-11 (Issaquah)	Complete
LWG2740	constexpr optional<T>::operator->	2016-11 (Issaquah)	Complete
LWG2742	Inconsistent string interface taking string_view	2016-11 (Issaquah)	Complete
LWG2744	any’s in_place constructors	2016-11 (Issaquah)	Complete
LWG2745	[fund.ts.v2] Implementability of LWG 2451	2016-11 (Issaquah)	Complete
LWG2747	Possibly redundant std::move in [alg.foreach]	2016-11 (Issaquah)	Complete
LWG2748	swappable traits for optionals	2016-11 (Issaquah)	Complete
LWG2749	swappable traits for variants	2016-11 (Issaquah)	Complete
LWG2750	[fund.ts.v2] LWG 2451 conversion constructor constraint	2016-11 (Issaquah)	Nothing To Do
LWG2752	“Throws:” clauses of async and packaged_task are unimplementable	2016-11 (Issaquah)	Nothing To Do
LWG2755	[string.view.io] uses non-existent basic_string_view::to_string function	2016-11 (Issaquah)	Complete
LWG2756	C++ WP optional<T> should ‘forward’ T’s implicit conversions	2016-11 (Issaquah)	Complete
LWG2758	std::string{}.assign(“ABCDE”, 0, 1) is ambiguous	2016-11 (Issaquah)	Complete
LWG2759	gcd / lcm and bool for the WP	2016-11 (Issaquah)	Complete
LWG2760	non-const basic_string::data should not invalidate iterators	2016-11 (Issaquah)	Complete
LWG2765	Did LWG 1123 go too far?	2016-11 (Issaquah)	Complete
LWG2767	not_fn call_wrapper can form invalid types	2016-11 (Issaquah)	Complete
LWG2771	Broken Effects of some basic_string::compare functions in terms of basic_string_view	2016-11 (Issaquah)	Complete
LWG2773	Making std::ignore constexpr	2016-11 (Issaquah)	Complete
LWG2777	basic_string_view::copy should use char_traits::copy	2016-11 (Issaquah)	Complete
LWG2778	basic_string_view is missing constexpr	2016-11 (Issaquah)	Complete
LWG2260	Missing requirement for Allocator::pointer	2017-02 (Kona)	Complete
LWG2676	Provide filesystem::path overloads for File-based streams	2017-02 (Kona)	Complete
LWG2768	any_cast and move semantics	2017-02 (Kona)	Complete
LWG2769	Redundant const in the return type of any_cast(const any&)	2017-02 (Kona)	Complete
LWG2781	Contradictory requirements for std::function and std::reference_wrapper	2017-02 (Kona)	Complete
LWG2782	scoped_allocator_adaptor constructors must be constrained	2017-02 (Kona)	Complete
LWG2784	Resolution to LWG 2484 is missing “otherwise, no effects” and is hard to parse	2017-02 (Kona)	Complete
LWG2785	quoted should work with basic_string_view	2017-02 (Kona)	Complete
LWG2786	Annex C should mention shared_ptr changes for array support	2017-02 (Kona)	Complete
LWG2787	§[file_status.cons] doesn’t match class definition	2017-02 (Kona)	Complete
LWG2788	basic_string range mutators unintentionally require a default constructible allocator	2017-02 (Kona)	Complete
LWG2789	Equivalence of contained objects	2017-02 (Kona)	Complete
LWG2790	Missing specification of istreambuf_iterator::operator->	2017-02 (Kona)	Complete
LWG2794	Missing requirements for allocator pointers	2017-02 (Kona)	Nothing To Do
LWG2795	§[global.functions] provides incorrect example of ADL use	2017-02 (Kona)	Complete
LWG2796	tuple should be a literal type	2017-02 (Kona)	Complete
LWG2801	Default-constructibility of unique_ptr	2017-02 (Kona)	Complete
LWG2802	shared_ptr constructor requirements for a deleter	2017-02 (Kona)	Complete
LWG2804	Unconditional constexpr default constructor for istream_iterator	2017-02 (Kona)	Complete
LWG2806	Base class of bad_optional_access	2017-02 (Kona)	Complete
LWG2807	std::invoke should use std::is_nothrow_callable	2017-02 (Kona)	Complete
LWG2812	Range access is available with <string_view>	2017-02 (Kona)	Complete
LWG2824	list::sort should say that the order of elements is unspecified if an exception is thrown	2017-02 (Kona)	Complete
LWG2826	string_view iterators use old wording	2017-02 (Kona)	Complete
LWG2834	Resolution LWG 2223 is missing wording about end iterators	2017-02 (Kona)	Complete
LWG2835	LWG 2536 seems to misspecify <tgmath.h>	2017-02 (Kona)	Complete
LWG2837	gcd and lcm should support a wider range of input values	2017-02 (Kona)	Complete
LWG2838	is_literal_type specification needs a little cleanup	2017-02 (Kona)	Complete
LWG2842	in_place_t check for optional::optional(U&&) should decay U	2017-02 (Kona)	Complete
LWG2850	std::function move constructor does unnecessary work	2017-02 (Kona)	Complete
LWG2853	Possible inconsistency in specification of erase in [vector.modifiers]	2017-02 (Kona)	Complete
LWG2855	std::throw_with_nested(“string_literal”)	2017-02 (Kona)	Complete
LWG2857	{variant,optional,any}::emplace should return the constructed value	2017-02 (Kona)	Complete
LWG2861	basic_string should require that charT match traits::char_type	2017-02 (Kona)	Complete
LWG2866	Incorrect derived classes constraints	2017-02 (Kona)	Nothing To Do
LWG2868	Missing specification of bad_any_cast::what()	2017-02 (Kona)	Complete
LWG2872	Add definition for direct-non-list-initialization	2017-02 (Kona)	Complete
LWG2873	Add noexcept to several shared_ptr related functions	2017-02 (Kona)	Complete
LWG2874	Constructor shared_ptr::shared_ptr(Y*) should be constrained	2017-02 (Kona)	Complete	13
LWG2875	shared_ptr::shared_ptr(Y*, D, […]) constructors should be constrained	2017-02 (Kona)	Complete
LWG2876	shared_ptr::shared_ptr(const weak_ptr<Y>&) constructor should be constrained	2017-02 (Kona)	Complete	14
LWG2878	Missing DefaultConstructible requirement for istream_iterator default constructor	2017-02 (Kona)	Complete
LWG2890	The definition of ‘object state’ applies only to class types	2017-02 (Kona)	Complete
LWG2900	The copy and move constructors of optional are not constexpr	2017-02 (Kona)	Complete
LWG2903	The form of initialization for the emplace-constructors is not specified	2017-02 (Kona)	Complete
LWG2904	Make variant move-assignment more exception safe	2017-02 (Kona)	Complete
LWG2905	is_constructible_v<unique_ptr<P, D>, P, D const &> should be false when D is not copy constructible	2017-02 (Kona)	Complete
LWG2908	The less-than operator for shared pointers could do more	2017-02 (Kona)	Complete
LWG2911	An is_aggregate type trait is needed	2017-02 (Kona)	Complete
LWG2921	packaged_task and type-erased allocators	2017-02 (Kona)	Complete	20	Originally implemented in LLVM 6 but reverted later. Old documentation incorrectly said it was implemented.
LWG2934	optional<const T> doesn’t compare with T	2017-02 (Kona)	Complete
LWG2901	Variants cannot properly support allocators	2017-07 (Toronto)	Complete
LWG2955	to_chars / from_chars depend on std::string	2017-07 (Toronto)	Nothing To Do		Resolved by P0682R1
LWG2956	filesystem::canonical() still defined in terms of absolute(p, base)	2017-07 (Toronto)	Complete