[ub] cleanups and feedback from initial reviewers#8739

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notadragon wants to merge 271 commits intocplusplus:ub-ifndrfrom

notadragon:ub-ifndr-cwgreview1

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Commits on Jan 30, 2026

Commits on Jan 31, 2026

[value.error.codes] Fix indefinite article (#8730)
Andreas-Krug
authored

Commits on Feb 3, 2026

[concept.comparisoncommontype] Add period to end of sentence (#8731)
Andreas-Krug
authored

Commits on Feb 6, 2026

[util.smartptr.shared.create] Add \tcode for double[2] in comment

Andreas-Krug
authored and
jwakely
committed
[alg.replace] Fix indentation (#8733)
Andreas-Krug
authored

Commits on Feb 9, 2026

[fs.op.last.write.time] Fix indentation (#8735)
Andreas-Krug
authored

Commits on Feb 12, 2026

Commits on Feb 13, 2026

[flat.map.cons.alloc] Remove superfluous \linebreak (#8745)
Andreas-Krug
authored

Commits on Feb 18, 2026

Commits on Feb 22, 2026

[alg.remove] Use E(i) for predicate on iterator i (#8760)
dangelog
authored

Commits on Feb 24, 2026

Commits on Feb 25, 2026

Commits on Mar 6, 2026

[mdspan.layout.leftpad.cons] Add missing \tcode

timsong-cpp
authored and
jwakely
committed

Commits on Mar 16, 2026

[check] Make check-output.sh tolerate new memoir version

jensmaurer
authored and
tkoeppe
committed
[istream.unformatted] Add right parenthesis

Andreas-Krug
authored and
tkoeppe
committed
[linalg.algs.blas2.rank2] Add whitespace after comma

Andreas-Krug
authored and
tkoeppe
committed

Commits on Mar 17, 2026

Commits on Mar 19, 2026

[exec.adapt.obj] Add \tcode for arg (#8796)
Andreas-Krug
authored

Commits on Mar 21, 2026

Commits on Mar 22, 2026

[vector.bool.fmt][container.adaptors.format] Add missing `constexpr` and other missed edits (#8768)
frederick-vs-ja
authored

Commits on Mar 23, 2026

Commits on Mar 25, 2026

Commits on Mar 26, 2026

[diff.basic] Use enum example instead of example outdated since C99

hubert-reinterpretcast
authored and
tkoeppe
committed
[diff.basic] Stop claiming, as harmless, type-based aliasing violations

hubert-reinterpretcast
authored and
tkoeppe
committed
[intro.compliance.general] Mark documentation encouragement as recommended practice

eisenwave
authored and
tkoeppe
committed
[basic.stc.dynamic] Spell out compound type names

lprv
authored and
tkoeppe
committed
[lex.key] Emphasize that keywords are created in phase 6

jensmaurer
authored and
tkoeppe
committed
Clarify pack-index-specifier rules

brevzin
authored and
tkoeppe
committed
[basic.fundamental] Strike explanatory sentence; touch up note

lprv
authored and
tkoeppe
committed
[basic.extended.fp] Replace "typedef-name" with "type alias"

lprv
authored and
tkoeppe
committed
[intro.refs], [numeric.limits] Remove all references to ISO/IEC 10967-1:2012

eisenwave
authored and
tkoeppe
committed
[basic.start.static] Improve readability of example

lprv
authored and
tkoeppe
committed
[stmt.pre] Streamline decl-specifier restrictions on conditions, etc.

hubert-reinterpretcast
authored and
tkoeppe
committed
[temp.point] Itemize long conditionals in three paragraphs

eisenwave
authored and
tkoeppe
committed
[meta.syn] Add function parameter names

hewillk
authored and
tkoeppe
committed
[expr.const] Introduce subclauses

jensmaurer
authored and
tkoeppe
committed
Refine cross references into [expr.const]

opensdh
authored and
tkoeppe
committed
[expr.const.defns] Fix comment alignment (#8814)
Tsche
authored
[basic.lookup.unqual] Rephrase to avoid incorrect use of term

lprv
authored and
tkoeppe
committed
[time.syn] Use `\placeholder` instead of `\term`

frederick-vs-ja
authored and
tkoeppe
committed
[class.qual] Formatting placeholder consistently as maths (#8610)
lprv
authored
[iostream.forward.overview] Add missing mentions of spanbuf and spanstreams

frederick-vs-ja
authored and
tkoeppe
committed
[iostream.forward.overview] Say "designate specialization".

frederick-vs-ja
authored and
tkoeppe
committed

Commits on Mar 27, 2026

Commits on Mar 28, 2026

[saferecl.rcu.domain.func] Fix indentation

Andreas-Krug
authored and
tkoeppe
committed
[execution.syn] Fix comment alignment

Andreas-Krug
authored and
tkoeppe
committed
[meta.reflection.queries] Use math font consistently

timsong-cpp
authored and
tkoeppe
committed
[forward] Add \tcode for literals

Andreas-Krug
authored and
tkoeppe
committed
[exec.snd.expos] Delete unused expos-only concept "completion-tag".
tkoeppe
committed
[dcl.struct.bind] Fix tuple-like binding index to use SB_i instead of v_i

abhinavagarwal07
authored and
tkoeppe
committed
[basic] Do not hyphenate "potentially evaluated"

lprv
authored and
tkoeppe
committed
[expr] Do not hyphenate "potentially evaluated"

lprv
authored and
tkoeppe
committed
[dcl] Do not hyphenate "potentially evaluated"

lprv
authored and
tkoeppe
committed
[temp.over.link] Do not hyphenate "potentially evaluated"

lprv
authored and
tkoeppe
committed

Commits on Mar 29, 2026

[includes] Fix indentation

Andreas-Krug
authored and
tkoeppe
committed
[coroutine.handle.general,coroutine.handle.noop.general] Place left curly bracket at end

Andreas-Krug
authored and
tkoeppe
committed

Commits on Apr 1, 2026

Commits on Apr 3, 2026

[mdspan.mdspan.cons] Fix typo (`is_nothrow_constructible` => `is_nothrow_constructible_v`)

cpplearner
authored and
tkoeppe
committed

Commits on Apr 4, 2026

[atomics.types.operations] Fix indentation (#8916)
Andreas-Krug
authored

Commits on Apr 8, 2026

[conv.rank] Add missing whitespace following \IsoC

eisenwave
authored and
tkoeppe
committed
CWG2609 Padding in class types

burblebee
authored and
tkoeppe
committed
CWG2744 Multiple objects of the same type at the same address

burblebee
authored and
tkoeppe
committed

Commits on Apr 11, 2026

CWG2765 Address comparisons between potentially non-unique objects during constant evaluation

burblebee
authored and
tkoeppe
committed
CWG2799 Inheriting default constructors

burblebee
authored and
tkoeppe
committed
CWG2947 Limiting macro expansion in pp-module

burblebee
authored and
tkoeppe
committed
CWG2966 Alignment and value representation of std::nullptr_t

burblebee
authored and
tkoeppe
committed
CWG2976 Transferring control out of a function

burblebee
authored and
tkoeppe
committed
CWG2983 Non-type template parameters are not variables

burblebee
authored and
tkoeppe
committed
CWG2992 Labels do not have names

burblebee
authored and
tkoeppe
committed
CWG3010 constexpr placement-new should require transparent replaceability

burblebee
authored and
tkoeppe
committed
CWG3029 Confusing note about ordinary character types for aligned memory areas

burblebee
authored and
tkoeppe
committed
CWG3035 Lambda expressions in anonymous unions

burblebee
authored and
tkoeppe
committed
CWG3058 "Program point" is not defined

burblebee
authored and
tkoeppe
committed
CWG3125 Token convertibility requirement in #if

burblebee
authored and
tkoeppe
committed
CWG3126 A module import needs a header-name as a token

burblebee
authored and
tkoeppe
committed
CWG3128 Potentially-throwing unevaluated operands

burblebee
authored and
tkoeppe
committed
CWG3129 Clarify which floating-point-literals are valid

burblebee
authored and
tkoeppe
committed
CWG3130 Naming function members of anonymous unions

burblebee
authored and
tkoeppe
committed
CWG3132 Unclear disambiguation rule for condition

burblebee
authored and
tkoeppe
committed
CWG3133 Cv-qualified types in built-in operator candidates

burblebee
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tkoeppe
committed
CWG3136 Constant expressions of type void

burblebee
authored and
tkoeppe
committed
CWG3142 Possible expansions of __LINE__ changing over time

burblebee
authored and
tkoeppe
committed
[cpp.predefined] Insert "The integer literal" as introducer.
tkoeppe
committed
CWG3148 Definition of "user-declared" special member function

burblebee
authored and
tkoeppe
committed
CWG3151 Closure types that are final

burblebee
authored and
tkoeppe
committed
CWG3153 Immediate-escalating defaulted comparison

burblebee
authored and
tkoeppe
committed
CWG3155 Escalation of virtual functions

burblebee
authored and
tkoeppe
committed
CWG3156 Handling of deleted functions in unevaluated lambda-captures

burblebee
authored and
tkoeppe
committed
CWG3157 Missing handling of operator new[] for deallocation function template matching

burblebee
authored and
tkoeppe
committed
CWG3171 Codify the strong ownership for modules

burblebee
authored and
tkoeppe
committed
CWG3173 Remove misleading footnote about as-if rule

burblebee
authored and
tkoeppe
committed

Commits on Apr 12, 2026

Merge 2026-03 CWG Motion 2
tkoeppe
authored
CWG3088 Clarify macro treatment of identifiers with special meaning

burblebee
authored and
tkoeppe
committed
CWG3119 for-range-declaration of an expansion-statement as a templated entity

burblebee
authored and
tkoeppe
committed
CWG3122 Inadequate value-dependence for reflect-expressions

burblebee
authored and
tkoeppe
committed
CWG3123 Global lookup for begin and end for expansion statements

burblebee
authored and
tkoeppe
committed
CWG3124 Disallow annotations on block-scope externs and non-unique friend declarations

burblebee
authored and
tkoeppe
committed
CWG3131 Value categories and types for the range in iterable expansion statements

burblebee
authored and
tkoeppe
committed
CWG3135 constexpr structured bindings with prvalues from tuples

burblebee
authored and
tkoeppe
committed
CWG3140 Allowing expansion over non-constant std::array

burblebee
authored and
tkoeppe
committed
CWG3143 Incorrect statement about enumerators for C23

burblebee
authored and
tkoeppe
committed
CWG3145 Uniqueness of annotations

burblebee
authored and
tkoeppe
committed
CWG3149 Rvalues in destructuring expansion statements

burblebee
authored and
tkoeppe
committed
CWG3162 Evaluation context of manifestly constant-evaluated expressions

burblebee
authored and
tkoeppe
committed
CWG3172 Reference to wrong placeholder

burblebee
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 3
tkoeppe
authored
P3924R1 Fix inappropriate font choices for "declaration"

eisenwave
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 4
tkoeppe
authored
P4136R2 #line is not in line with existing implementation

jensmaurer
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 5
tkoeppe
authored
P4004R1 Reconsider CWG 1395 "Partial ordering of variadic templates reconsidered"

jensmaurer
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 6
tkoeppe
authored
P3865R3 Class template argument deduction (CTAD) for type template template

eisenwave
authored and
tkoeppe
committed
[over.match.class.deduct] Add introductory "The alias template".
tkoeppe
committed
Merge 2026-03 CWG Motion 7
tkoeppe
authored
P3598R0 CWG 3158 - `const`-ification of Splice Expressions

eisenwave
authored and
tkoeppe
committed
[expr.prim.splice] Add introductory words "The expression".
tkoeppe
committed
Merge 2026-03 CWG Motion 8
tkoeppe
authored
P3726R2 Adjustments to Union Lifetime Rules

eisenwave
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 9
tkoeppe
committed
P4143R0 Constant evaluation when?

jensmaurer
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 10
tkoeppe
authored
P4149R1 Define "immediate context"

eisenwave
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 11
tkoeppe
authored
P3769R1 Clarification of placement new deallocation

jensmaurer
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 12
tkoeppe
authored
CWG3141 Unique objects from define_static_array

burblebee
authored and
tkoeppe
committed
Merge 2026-03 CWG Motion 13
tkoeppe
authored
LWG2414 Member function reentrancy should be implementation-defined

burblebee
authored and
tkoeppe
committed
LWG2746 Inconsistency between requirements for emplace between optional and variant

burblebee
authored and
tkoeppe
committed
LWG3504 condition_variable::wait_for is overspecified

burblebee
authored and
tkoeppe
committed
LWG3599 The const overload of lazy_split_view::begin should be constrained by const Pattern

burblebee
authored and
tkoeppe
committed
LWG4290 Missing Mandates clauses on is_sufficiently_aligned

burblebee
authored and
tkoeppe
committed
LWG4453 atomic_ref<cv T>::required_alignment should be the same as for T

burblebee
authored and
tkoeppe
committed
LWG4454 assert should forbid co_await and co_yield

burblebee
authored and
tkoeppe
committed
LWG4469 Names of parameters of addressable function shall remain unspecified

burblebee
authored and
tkoeppe
committed
LWG4472 std::atomic_ref<const T> can be constructed from temporaries

burblebee
authored and
tkoeppe
committed
LWG4486 integral-constant-like and constexpr-wrapper-like exposition-only concept duplication

burblebee
authored and
tkoeppe
committed
LWG4492 std::generate and std::ranges::generate wording is unclear for parallel algorithms

burblebee
authored and
tkoeppe
committed
LWG4496 Precedes vs Reachable in [meta.reflection]

burblebee
authored and
tkoeppe
committed
LWG4499 flat_set::insert_range specification may be problematic

burblebee
authored and
tkoeppe
committed
LWG4510 Ambiguity of std::ranges::advance and std::ranges::next when the difference type is also a sentinel type

burblebee
authored and
tkoeppe
committed
LWG4511 Inconsistency between the deduction guide of std::mdspan taking (data_handle_type, mapping_type, accessor_type) and the corresponding constructor

burblebee
authored and
tkoeppe
committed
LWG4512 The system_encoded_string() and generic_system_encoded_string() member functions of std::filesystem::path are misnamed

burblebee
authored and
tkoeppe
committed
LWG4535 Disallow user specialization of <simd> templates

burblebee
authored and
tkoeppe
committed
LWG4536 Type traits have inconsistent interactions with immediate functions

burblebee
authored and
tkoeppe
committed
LWG3831 Two-digit formatting of negative year is ambiguous

burblebee
authored and
tkoeppe
committed
LWG4090 Underspecified use of locale facets for locale-dependent std::format

burblebee
authored and
tkoeppe
committed
LWG4130 Preconditions for std::launder might be overly strict

burblebee
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tkoeppe
committed
LWG4259 P1148R0 changed the return values of searching functions of std::basic_string on some platforms

burblebee
authored and
tkoeppe
committed
LWG4324 unique_ptr<void>::operator* is not SFINAE-friendly

burblebee
authored and
tkoeppe
committed
LWG4378 Inconsistency between std::basic_string's data() and operator[] specification

burblebee
authored and
tkoeppe
committed
LWG4457 freestanding for stable_sort, stable_partition and inplace_merge

burblebee
authored and
tkoeppe
committed
LWG4460 Missing Throws: for last variant constructor

burblebee
authored and
tkoeppe
committed
LWG4467 hive::splice can throw bad_alloc

burblebee
authored and
tkoeppe
committed
LWG4468 [const.wrap.class] "operator decltype(auto)" is ill-formed

burblebee
authored and
tkoeppe
committed
LWG4474 "round_to_nearest" rounding mode is unclear

burblebee
authored and
tkoeppe
committed
LWG4477 Placement operator delete should be constexpr

burblebee
authored and
tkoeppe
committed
LWG4480 <stdatomic.h> should provide ATOMIC_CHAR8_T_LOCK_FREE

burblebee
authored and
tkoeppe
committed
LWG4481 Disallow chrono::duration<const T, P>

burblebee
authored and
tkoeppe
committed
LWG4483 Multidimensional arrays are not supported by meta::reflect_constant_array and related functions

burblebee
authored and
tkoeppe
committed
LWG4491 Rename submdspan_extents and submdspan_canonicalize_slices

burblebee
authored and
tkoeppe
committed
LWG4493 Specification for some functions of bit reference types seems missing

burblebee
authored and
tkoeppe
committed
LWG4500 constant_wrapper wording problems

burblebee
authored and
tkoeppe
committed
LWG4514 Missing absolute value of init in vector_two_norm and matrix_frob_norm

burblebee
authored and
tkoeppe
committed
LWG4517 data_member_spec should throw for cv-qualified unnamed bit-fields

burblebee
authored and
tkoeppe
committed
LWG4522 Clarify that std::format transcodes for std::wformat_strings

burblebee
authored and
tkoeppe
committed
LWG4523 constant_wrapper should assign to value

burblebee
authored and
tkoeppe
committed
LWG4525 task's final_suspend should move the result

burblebee
authored and
tkoeppe
committed
LWG4527 await_transform needs to use as_awaitable

burblebee
authored and
tkoeppe
committed
LWG4528 task needs get_completion_signatures()

burblebee
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tkoeppe
committed
LWG4529 task::promise_type::await_transform declaration and definition mismatch

burblebee
authored and
tkoeppe
committed
Merge 2026-03 LWG Motion 1
tkoeppe
authored

Commits on Apr 16, 2026

[std] Add Annex for undefined and IFNDR behavior

jensmaurer
authored and
joshuaberne
committed
[class.cdtor] Remove duplicate UB labels

jensmaurer
authored and
joshuaberne
committed
[expr.delete] Remove duplicate UB label

jensmaurer
authored and
joshuaberne
committed
[conv.fpint] Remove duplicate UB label

jensmaurer
authored and
joshuaberne
committed
[ifndr.lex] Replace C++ with \Cpp

jensmaurer
authored and
joshuaberne
committed
[ub,ifndr] Fix column alignment of comments

jensmaurer
authored and
joshuaberne
committed
[ifndr] Fix cross-references

jensmaurer
authored and
joshuaberne
committed
[ub] Replace non-ASCII chars

jensmaurer
authored and
joshuaberne
committed
[check] Handle ub/ifndr labels

jensmaurer
authored and
joshuaberne
committed
[check] Exclude [ub] and [ifndr] from sibling checking for now

jensmaurer
authored and
joshuaberne
committed
[ub.cpp.concat] Remove universal-character-name formation from ##; now well-defined

jensmaurer
authored and
joshuaberne
committed
[ifndr] Use codeblocktu

jensmaurer
authored and
joshuaberne
committed
Rename label expr.ass.overlap to expr.assign.overlap

jensmaurer
authored and
joshuaberne
committed
[ub.basic.stc.dynamic] Fix typo

jensmaurer
authored and
joshuaberne
committed
[ub] Fix some formatting (#7828)

jensmaurer
authored and
joshuaberne
committed
Remove class.dtor.not.class.type (#7835)

jensmaurer
authored and
joshuaberne
committed
Remove incorrect class.union.assignment.not.start.lifetime (#7833)

jensmaurer
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joshuaberne
committed
[ub.general,ifndr.general] Avoid hanging paragraphs by introducing 'General' subclauses (#7848)

jensmaurer
authored and
joshuaberne
committed
[ub] Add many missing entries to UB annex (#7864)

notadragon
and
joshuaberne
committed
[conv.fpint] Remove unreferenced \ubdef that causes an undefined symbol error

jensmaurer
authored and
joshuaberne
committed
[ub] small fixes to examples (#7890)

notadragon
authored and
joshuaberne
committed
[ub] Added all missing ubdefs to bring UB annex in line with P3100R2 list (#7888)

timuraudio
authored and
joshuaberne
committed
[ub] Adjust to undefined behavior removed by P2621R2

jensmaurer
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joshuaberne
committed
[ub,intro.progress] Added entry for UB due to lack of forward progress (#8335)

timuraudio
authored and
joshuaberne
committed
[ub] Remove lifetime.outside.pointer.static.cast

jensmaurer
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joshuaberne
committed
[ub] and [ifndr] remove extra line breaks after ubxref and ifndrxref (#8716)

notadragon
authored and
joshuaberne
committed
[ub] and [ifndr] fixes and updates after feedback from Christof Meerwald
joshuaberne
committed
[*] made sure ubdef and ifndrdef do not have preceding whitespaces and come before full stops
joshuaberne
committed
[ub] comment about library ub in the core wording
joshuaberne
committed
[ub] feedback from Shafik on ub annex
joshuaberne
committed
[ifndr] more feebdack from Shafik
joshuaberne
committed
[ifndr]: added missing entries brought up by Alisdair
joshuaberne
committed
[ifndr]: started with shafik's suggested examples and refined them a bit

notadragon
authored and
joshuaberne
committed
[ifndr] added comment on possibly non-NDR entry temp.names.sat.constraints

notadragon
authored and
joshuaberne
committed
[ifndr] fixing (hopefully) bad unary operator defined example
joshuaberne
committed
[ifndr]: added many missing ifndr types, removed temp.names.sat.constraints
joshuaberne
committed
ifndr: removing module ownership related ifndr (cwg3171)
joshuaberne
committed
ifndr: filled in many of the missing examples/TODOs
joshuaberne
committed
[ifndr]: cleaned up line wrapping of some comments
joshuaberne
committed