C++

Microsoft Visual Studio

STL

Implemented C++23 features:

• P1899R3: "stride_view" (#2981)
• P2446R2: "views::as_rvalue" (#3008)
• P2278R4: "cbegin should always return a constant iterator" (#3043, #3187, #3234)
• P2322R6: "ranges::fold" (#3099)
• P2165R4: "Compatibility between tuple, pair and tuple-like objects" (#3323, #3372)
• P2404R3: "Move-only types for equality_comparable_with, totally_ordered_with, and three_way_comparable_with" (#3345)
• P2164R9: "views::enumerate" (#3472)
• P2609R3: "Relaxing Ranges Just A Smidge" (#3486)
• P2321R2: "zip" (partial: #3508, #3546)
• P0009R18: "MDSPAN" (#3534, #3535, #3560, #3564, #3580, #3586, #3593, #3603, #3615, #3616, #3632, #3672, #3673, #3674, #3682, #3688, #3689, #3690, #3693, #3694, #3698, #3701, #3702, #3715, #3749, #3767, #3786, #3821, #3825, #3829, #3847, #3852, #4559)
• P2736R2: "Referencing The Unicode Standard" (#3556)
• P2374R4: "views::cartesian_product" (#3561)
• P2693R1: "Formatting thread::id, stacktrace_entry, and basic_stacktrace" (#3861)
• P2836R1: "basic_const_iterator Should Follow Its Underlying Type's Convertibility" (#4188)
• P2286R8: "Formatting Ranges" (#3913, #4642)
• P2502R2: "std::generator: Synchronous Coroutine Generator for Ranges" (partial: #4534, #4558, #4574, #4619, #4620, #4621)

Implemented C++26 features:

• P2510R3: "Formatting Pointers" (#4198)

Implemented LWG issues:

• LWG-3707: "chunk_view::outer-iterator::value_type::size should return unsigned type" (#2883)
• LWG-3515: "[stacktrace.basic.nonmem]: operator<< should be less templatized" (#3236)
• LWG-3810: "CTAD for basic_format_args" (#3421)
• LWG-3848: "slide_view missing base accessor" (#3410)
• LWG-3850: "views::as_const on empty_view<T> should return empty_view<const T>" (#3423)
• LWG-3851: "chunk_view::inner-iterator missing custom iter_move and iter_swap" (#3517)
• LWG-3853: "basic_const_iterator<volatile int*>::operator-> is ill-formed" (#3468)
• LWG-3862: "basic_const_iterator's common_type specialization is underconstrained" (#3471)
• LWG-3872: "basic_const_iterator should have custom iter_move" (#3470)
• LWG-3875: "std::ranges::repeat_view<T, IntegerClass>::iterator may be ill-formed" (#3485)
• LWG-3880: "Clarify operator+= complexity for {chunk,stride}_view::iterator" (#3554)

Fixed bugs:

• #3113: "<algorithm>: ranges::is_permutation's helper lambda does not specify return type"
• #3380: "<system_error>: Use uglified [[clang::require_constant_initialization]] attribute"
• #3493: "<ranges>: Fix misused list-initializations"
• #3551: "<ranges>: Fix ranges::equal for ranges with integer-class range_difference_t"
• #3678: "Improve _(Add|Multiply)_with_overflow_check"
• #3733: "<ranges>: Fix cartesian_product_view::size in debug mode"

Reported bugs:

• #2312: "<ranges>: using views::reverse on ranges::reverse_view lvalue is broken"
• #3009: "<iterator>: move_sentinel should be unwrappable"
• #3010: "Range algorithms don't work when used with unwrappable iterators and custom sentinels"
• #3392: "<ranges>: views::repeat(...) | views::take(...) is not always a valid range" (fixed by #3485)
• #3550: "<ranges>: ranges::equal does not work for ranges with integer-class range_difference_t" (fixed by #3551)
• #3644: "<chrono>: Some (weird) durations still cannot be formatted"
• #3648: "<chrono>: ambiguous_local_time's message is slightly incorrect"
• StephanTLavavej/STL#18: "<variant>: Constructor inheritance causes ICE when class in named module inherits from class imported from module std"
• StephanTLavavej/STL#23: "<ranges>: Usage of ranges::iterator_t causes ICE"

Other improvements:

• #2696: "Update _MSVC_STL_UPDATE (may 2022)"
• #3089: "Cleanup views::as_rvalue tests"
• #3117: "Constexprize bind_front and bind_back tests"
• #3350: "Improve views::elements tests"
• #3390: "Improve views::drop(_while) and views::take(_while) tests"
• #3391: "<ranges>: Add missing test coverage for ranges::view_interface::c(begin|end)"
• #3553: "<ranges>: Test c(begin|end) members of range factories"
• #3610: "Testing: Check new C++23 CPOs"
• #3753: "Make P2415R2_owning_view/test.cpp test something"
• #3839: "<ranges>: Improve implementation of recommended practices in views::cartesian_product"
• #3919: "Modernize validate.cpp: Use <print> instead of <cstdio>"
• #3920: "Testing: check c(begin|end) members of some C++23 ranges"

MSVC compiler

Reported bugs:

• DevCom-10078204: "[C++20] (Exporting-)Importing module partition with class that inherits constructor from class imported from standard header unit causes ICE"
• DevCom-10187107: "const_cast cannot be used in constexpr context"
• DevCom-10269323: "[C++] Post-increment operator cannot refer to this pointer in noexcept specifier"
• DecCom-10302378: "[C++][Concepts][Regression] Expanding parameter pack in std::invoke_result_t may cause ICE"
• DevCom-10359857: "[C++][Modules] std::mdspan is unusable with C++20 modules"
• DevCom-10360833: "[C++][Concepts] CTAD does not work with constrained constructors when requires expression contains nested alias"
• DevCom-10398426: "/analyze:only: bogus "warning C6287: Redundant code" when expanding integer pack that contains identical values"
• DevCom-10404496: "[C++][Modules] Using std::views::iota in member function in module causes ICE"
• DevCom-10404498: "[C++][Modules] Using std::views::repeat in member functions gives bogus error about lack of compare header"

LLVM

libc++

Implemented C++23 features:

• P2443R1: "[libc++][ranges] Implement P2443R1: views::chunk_by" (Phabricator D144767)
• P2770R0: "[libc++] P2770R0: "Stashing stashing iterators for proper flattening" (#66033)
• P2441R2: "[libc++] Implement views::join_with" (In progress: #65536)
• P2602R2: "[libc++] P2602R2 Poison Pills are Too Toxic" (#74534)
• P2387R3: "[libc++] Implement bind_back" (#81055)
• P2714R1: "[libc++] Implement not_fn<NTTP>" (In progress: #86133)

Reported bugs:

• #58315: "[libc++][format] Strings are incorrectly aligned when alignment is not specified"
• #59763: "[libc++][format] String literals inside of tuple and pair should be escaped"
• #60123: "[libc++][format] Negation of LLONG_MIN (UB) when formatting chrono::duration"
• #60164: "[libc++][format] Some contiguous ranges cannot be formatted due to lack of data or size member functions"
• #60658: "[libc++][ranges] views::drop uses non-reserved identifiers dist and clamped"
• #60986: "[libc++][ranges] Feature test macro for views::as_rvalue is missing"
• #61314: "[libc++][format] Should formatter<vec-bool-ref> be default constructible without <format> include?"
• #62073: "[libc++][format] Should operator<<(thread::id) care about fmtflags in C++23?"
• #62074: "[libc++][format][chrono] Problems with chrono-specs with short lifetime"
• #90196: "[libc++][format] Formatting range with m range-type is incorrect"

Clang

Implemented features:

• __builtin_FUNCSIG: "[Clang][clang-cl] Implement __builtin_FUNCSIG" (Phabricator D150183)

Reported bugs:

• #59827: "[Clang][concepts] Conditional explicit specifier is checked too early in constrained constructor"
• #62290: "[Clang][concepts][regression] Construction of a class X nested in class template is ill-formed when X has class template friend with specific constraints"