Merge pull request #6136 from TylerMSFT/conformance

update conformance support

Author: prmerger-automator[bot]

docs/overview/visual-cpp-language-conformance.md

@@ -1,7 +1,7 @@
 ---
 title: "Microsoft C/C++ language conformance"
 description: "Microsoft C and C++ conformance updates by Visual Studio version."
-ms.date: 11/04/2025
+ms.date: 11/10/2025
 ms.service: "visual-cpp"
 ms.subservice: "cpp-lang"
 ---
@@ -174,55 +174,60 @@ For details on conformance improvements, see [C++ conformance improvements in Vi
 | &emsp;[`P1073R3 Immediate functions`](https://wg21.link/P1073R3) | VS 2019 16.10 <sup>[20](#note_20)</sup> |
 | &emsp;[`P1143R2 constinit`](https://wg21.link/P1143R2) | VS 2019 16.10 <sup>[20](#note_20)</sup> |
 | &emsp;[`P1353R0 Missing feature-test macros`](https://wg21.link/P1353R0) | VS 2019 16.10 <sup>[20](#note_20)</sup> |
-| &emsp;[`P0735R1 Interaction of memory_order_consume with release sequences`](https://wg21.link/P0735R1) | N/A |
-| &emsp;[`P1236R1 Signed integers are two's complement`](https://wg21.link/P1236R1) | N/A |
+| &emsp;[`P0735R1 Interaction of memory_order_consume with release sequences`](https://wg21.link/P0735R1) | VS 2022 v17.14 |
+| &emsp;[`P1236R1 Signed integers are two's complement`](https://wg21.link/P1236R1) | VS 2022 v17.14 |
 | **C++23 Core language features** | **Supported** |
-| &emsp;[`P0330R8 Literal Suffix for (signed) size_t`](https://wg21.link/p0330r8) | no |
-| &emsp;[`P0847R7 Deducing this`](https://wg21.link/p0847r7) | no |
-| &emsp;[`P0849R8 auto(x): decay-copy in the language`](https://wg21.link/p0849r8) | no |
-| &emsp;[`P1102R2 Down with ()!`](https://wg21.link/p1102r2) | no |
-| &emsp;[`P1169R4 static operator()`](https://wg21.link/p1169r4) | no |
-| &emsp;[`P1401R5 Narrowing contextual conversions to bool`](https://wg21.link/p1401r5) | no |
-| &emsp;[`P1467R9 Extended floating-point types and standard names`](https://wg21.link/p1467r9) | no |
+| &emsp;[`P0330R8 Literal Suffix for (signed) size_t`](https://wg21.link/p0330r8) | VS 2022 17.13 <sup>[23](#note_23)</sup> |
+| &emsp;[`P0847R7 Deducing this`](https://wg21.link/p0847r7) | VS 2022 17.13 <sup>[23](#note_23)</sup> |
+| &emsp;[`P0849R8 auto(x): decay-copy in the language`](https://wg21.link/p0849r8) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
+| &emsp;[`P1102R2 Down with ()!`](https://wg21.link/p1102r2) | VS 2022 17.14 <sup>[23](#note_23)</sup> |
+| &emsp;[`P1169R4 static operator()`](https://wg21.link/p1169r4) | VS 2022 17.14 <sup>[23](#note_23)</sup> |
+| &emsp;[`P1401R5 Narrowing contextual conversions to bool`](https://wg21.link/p1401r5) | VS 2022 17.14 <sup>[23](#note_23)</sup> |
+| &emsp;[`P1467R9 Extended floating-point types and standard names`](https://wg21.link/p1467r9) | No <sup>[U](#note_U)</sup> |
 | &emsp;[`P1774R8 Portable assumptions`](https://wg21.link/p1774r8) | no |
-| &emsp;[`P1787R6 Declarations and where to find them`](https://wg21.link/p1787r6) | no |
+| &emsp;[`P1787R6 Declarations and where to find them`](https://wg21.link/p1787r6) | No change required |
 | &emsp;[`P1847R4 Make declaration order layout mandated`](https://wg21.link/p1847r4) | VS 2022 17.0 <sup>[23](#note_23)</sup> |
-| &emsp;[`P1938R3 if consteval`](https://wg21.link/p1938r3) | no |
-| &emsp;[`P1949R7 C++ Identifier Syntax using Unicode Standard Annex 31`](https://wg21.link/p1949r7) | no |
+| &emsp;[`P1938R3 if consteval`](https://wg21.link/p1938r3) | VS 2022 17.14 <sup>[23](#note_23)</sup> |
+| &emsp;[`P1949R7 C++ Identifier Syntax using Unicode Standard Annex 31`](https://wg21.link/p1949r7) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
 | &emsp;[`P2029R4 Proposed resolution for core issues 411, 1656, and 2333; numeric and universal character escapes in character and string literals`](https://wg21.link/p2029r4) | no |
-| &emsp;[`P2036R3 Change scope of lambda trailing-return-type`](https://wg21.link/p2036r3) | no |
+| &emsp;[`P2036R3 Change scope of lambda trailing-return-type`](https://wg21.link/p2036r3) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
 | &emsp;[`P2071R2 Named universal character escapes`](https://wg21.link/p2071r2) | no |
-| &emsp;[`P2128R6 Multidimensional subscript operator`](https://wg21.link/p2128r6) | no |
-| &emsp;[`P2156R1 Allow Duplicate Attributes`](https://wg21.link/p2156r1) | no |
-| &emsp;[`P2173R1 Attributes on Lambda-Expressions`](https://wg21.link/p2173r1) | no |
+| &emsp;[`P2128R6 Multidimensional subscript operator`](https://wg21.link/p2128r6) | VS 2022 17.12 <sup>[23](#note_23)</sup> |
+| &emsp;[`P2156R1 Allow Duplicate Attributes`](https://wg21.link/p2156r1) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
+| &emsp;[`P2173R1 Attributes on Lambda-Expressions`](https://wg21.link/p2173r1) | VS 2022 17.14 <sup>[23](#note_23)</sup> |
 | &emsp;[`P2186R2 Remove Garbage Collection Support`](https://wg21.link/p2186r2) | VS 2022 17.0 <sup>[23](#note_23)</sup> |
-| &emsp;[`P2201R1 Mixed string literal concatenation`](https://wg21.link/p2201r1) | no |
-| &emsp;[`P2223R2 Trimming whitespaces before line splicing`](https://wg21.link/p2223r2) | no |
-| &emsp;[`P2242R3 Non-literal variables (and labels and gotos) in constexpr functions`](https://wg21.link/p2242r3) | no |
+| &emsp;[`P2201R1 Mixed string literal concatenation`](https://wg21.link/p2201r1) | VS 2022 17.14 |
+| &emsp;[`P2223R2 Trimming whitespaces before line splicing`](https://wg21.link/p2223r2) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
+| &emsp;[`P2242R3 Non-literal variables (and labels and gotos) in constexpr functions`](https://wg21.link/p2242r3) | VS 2022 17.14 <sup>[23](#note_23)</sup> |
 | &emsp;[`P2246R1 Character encoding of diagnostic text`](https://wg21.link/p2246r1) | VS 2022 17.0 <sup>[23](#note_23)</sup> |
-| &emsp;[`P2280R4 Using unknown pointers and references in constant expressions`](https://wg21.link/p2280r4) | no |
-| &emsp;[`P2290R3 Delimited escape sequences`](https://wg21.link/p2290r3) | no |
-| &emsp;[`P2295R6 Support for UTF-8 as a portable source file encoding`](https://wg21.link/p2295r6) | no |
+| &emsp;[`P2266R3 Simpler implicit move`](https://wg21.link/p2266r3) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
+| &emsp;[`P2280R4 Using unknown pointers and references in constant expressions`](https://wg21.link/p2280r4) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
+| &emsp;[`P2290R3 Delimited escape sequences`](https://wg21.link/p2290r3) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
+| &emsp;[`P2295R6 Support for UTF-8 as a portable source file encoding`](https://wg21.link/p2295r6) | <sup>[V](#note_V)</sup> |
 | &emsp;[`P2314R4 Character sets and encodings`](https://wg21.link/p2314r4) | no |
 | &emsp;[`P2316R2 Consistent character literal encoding`](https://wg21.link/p2316r2) | VS 2022 17.0 <sup>[23](#note_23)</sup> |
 | &emsp;[`P2324R2 Labels at the end of compound statements (C compatibility)`](https://wg21.link/p2324r2) | no |
-| &emsp;[`P2327R1 De-deprecating volatile compound operations`](https://wg21.link/p2327r1) | no |
-| &emsp;[`P2334R1 preprocessing directives elifdef and elifndef`](https://wg21.link/p2334r1) | no |
-| &emsp;[`P2360R0 Extend init-statement to allow alias-declaration`](https://wg21.link/p2360r0) | no |
+| &emsp;[`P2327R1 De-deprecating volatile compound operations`](https://wg21.link/p2327r1) | VS 2022 v17.14 |
+| &emsp;[`P2334R1 preprocessing directives elifdef and elifndef`](https://wg21.link/p2334r1) | VS 2022 17.10 <sup>[23](#note_23)</sup> |
+| &emsp;[`P2360R0 Extend init-statement to allow alias-declaration`](https://wg21.link/p2360r0) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
 | &emsp;[`P2362R3 Remove non-encodable wide character literals and multicharacter wide character literals`](https://wg21.link/p2362r3) | no |
-| &emsp;[`P2437R1 Support for #warning`](https://wg21.link/p2437r1) | no |
+| &emsp;[`P2437R1 Support for #warning`](https://wg21.link/p2437r1) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
 | &emsp;[`P2448R2 Relaxing some constexpr restrictions`](https://wg21.link/p2448r2) | no |
-| &emsp;[`P2460R2 Relax requirements on wchar_t to match existing practices`](https://wg21.link/p2460r2) | no |
-| &emsp;[`P2468R2 The Equality Operator You Are Looking For`](https://wg21.link/p2468r2) | no |
-| &emsp;[`P2493R0 Missing feature test macros for C++20 core papers`](https://wg21.link/p2493r0) | no |
+| &emsp;[`P2460R2 Relax requirements on wchar_t to match existing practices`](https://wg21.link/p2460r2) | VS 2022 v17.14 |
+| &emsp;[`P2468R2 The Equality Operator You Are Looking For`](https://wg21.link/p2468r2) | VS 2022 17.6 <sup>[23](#note_23)</sup> |
+| &emsp;[`P2493R0 Missing feature test macros for C++20 core papers`](https://wg21.link/p2493r0) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
 | &emsp;[`P2513R4 char8_t Compatibility and Portability Fix`](https://wg21.link/p2513r4) | VS 2022 17.4 <sup>[DR](#note_DR)</sup> |
-| &emsp;[`P2579R0 Mitigation strategies for P2036 ”Changing scope for lambda trailing-return-type”`](https://wg21.link/p2579r0) | no |
+| &emsp;[`P2579R0 Mitigation strategies for P2036 "Changing scope for lambda trailing-return-type"`](https://wg21.link/p2579r0) | MSVC Build Tools version 14.50 <sup>[24](#note_24)</sup> |
 | &emsp;[`P2582R1 Wording for class template argument deduction from inherited constructors`](https://wg21.link/p2582r1) | no |
 
 ## C++ Standard library features
 
 A more detailed listing of Standard Library features and bug fixes by product version is available on the [GitHub Microsoft STL wiki Changelog](https://github.com/microsoft/STL/wiki/Changelog) page.
 
+For the latest information about ongoing conformance work, see:
+- [STL C++23 Features](https://github.com/orgs/microsoft/projects/1142/views/2).
+- [STL C++26 Features](https://github.com/orgs/microsoft/projects/1143/views/2).
+
 | Feature | Supported |
 |--|--|
 | **C++14 Standard library features** | **Supported** |
@@ -437,7 +442,7 @@ A more detailed listing of Standard Library features and bug fixes by product ve
 | &emsp;[`P1208R6 <source_location>`](https://wg21.link/P1208R6) | VS 2019 16.10 <sup>[20](#note_20)</sup> |
 | &emsp;[`P1502R1 Standard Library Header Units`](https://wg21.link/P1502R1) | VS 2019 16.10 <sup>[20](#note_20)</sup> |
 | &emsp;[`P1614R2 Adding Spaceship <=> To The Library`](https://wg21.link/P1614R2) | VS 2019 16.10 <sup>[20](#note_20)</sup> |
-| &emsp;[`P1285R0 Improving Completeness Requirements For Type Traits`](https://wg21.link/P1285R0) | N/A |
+| &emsp;[`P1285R0 Improving Completeness Requirements For Type Traits`](https://wg21.link/P1285R0) | VS 2022 v17.14 |
 | **C++20 Standard library features (Defect reports)** | **Supported** |
 | &emsp;[`P2325R3 Views Should Not Be Required To Be Default Constructible`](https://wg21.link/P2325r3) | VS 2022 17.0 <sup>[20abi](#note_20abi)</sup> |
 | &emsp;[`P2328R1 join_view should join all views of ranges`](https://wg21.link/P2328R1) | VS 2022 17.0 <sup>[20abi](#note_20abi)</sup> |
@@ -635,6 +640,10 @@ These algorithms aren't presently parallelized:
 
 <a name="note_T"></a> **T** `<stdatomic.h>` is currently supported when compiled as C++ (`/std:c++latest`). It isn't yet supported when compiled as C (`/std:c11` and `/std:c17`)
 
+<a name="note_U"></a> **U** Extended floating-point types are an optional C++23 feature. This feature won't be implemented until C++23 standardization is finalized.
+
+<a name="note_V"></a> **V** Use the compiler options `/source-charset:utf-8` and `/we4828` to treat source files as UTF-8 encoded.
+
 <a name="note_14"></a> **14** These C++17 and C++20 features are always enabled, even when [`/std:c++14`](../build/reference/std-specify-language-standard-version.md) (the default) is specified. The reason is either because the feature was implemented before the introduction of the **`/std`** options, or because conditional implementation was undesirably complex.
 
 <a name="note_17"></a> **17** These features are enabled by the [`/std:c++17`](../build/reference/std-specify-language-standard-version.md) or later compiler option.