title: "Microsoft C++ Language Conformance Table"

ms.technology: "cpp-language"

ms.assetid: 475da6e9-0d78-4b4e-bd23-f41c406c4efe

author: "corob-msft"

|----|---|

|__C++17 Core Language Features (Defect Reports)__|__Supported__|

|  [P0702R1 Fixing class template argument deduction for initializer-list ctors](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0702r1.html)|VS 2017 15.7 ^{[17](#note_17)}|

|  [P0961R1 Relaxing the structured bindings customization point finding rules](http://open-std.org/JTC1/SC22/WG21/docs/papers/2018/p0961r1.html)|VS 2019 16.0 ^{[17](#note_17)}|

|  [P0969R0 Allowing structured bindings to accessible members](http://open-std.org/JTC1/SC22/WG21/docs/papers/2018/p0969r0.pdf)|VS 2019 16.0 ^{[17](#note_17)}|

|  [P0929R2 Checking for abstract class types](https://wg21.link/P0929R2)|No|

|  [P1009R2 Array size deduction in new-expressions](https://wg21.link/P1009R2)|No|

|  [P1286R2 Contra CWG DR1778](https://wg21.link/P1286R2)|No|

|Feature Area| |

|----|---|

|__C++20 Core Language Features__|__Supported__|

|  [P0704R1 Fixing const lvalue ref-qualified pointers to members](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0704r1.html)|VS 2015 ^{[14](#note_14)}|

|  [P1330R0 Changing the active member of a union inside constexpr](https://wg21.link/P1330R0)|VS 2017 15.0 ^{[14](#note_14)}|

|  [P0329R4 Designated initialization](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0329r4.pdf)|VS 2019 16.1 ^{[20](#note_20)}|

|  [P0409R2 Allowing lambda-capture \[=, this\]](http://open-std.org/JTC1/SC22/WG21/docs/papers/2017/p0409r2.html)|VS 2019 16.1 ^{[20](#note_20)}|

|  [P0941R2 Feature-test macros](https://wg21.link/P0941R2)|VS 2019 16.0 ^{[14](#note_14)}|

|  [P1008R1 Prohibiting aggregates with user-declared constructors](https://wg21.link/P1008R1)|VS 2019 16.0 ^{[20](#note_20)}|

|  [P0846R0 ADL and function templates that are not visible](https://wg21.link/P0846R0)|VS 2019 16.1 ^{[20](#note_20)}|

|  [P0641R2 const mismatch with defaulted copy constructor](https://wg21.link/P0641R2)|Partial|

|  [P0315R4 Allowing lambdas in unevaluated contexts](https://wg21.link/P0315R4)|No|

|  [P0409R2 Allowing lambda-capture \[=, this\]](https://wg21.link/P0409R2)|No|

|  [P0479R5 \[\[likely\]\] and \[\[unlikely\]\] attributes](https://wg21.link/P0479R5)|No|

|  [P0542R5 Contracts](https://wg21.link/P0542R5)|No|

|  [P0614R1 Range-based for-loops with initializers](https://wg21.link/P0614R1)|No|

|  [P0912R5 Coroutines](https://wg21.link/P0912R5)|No|

|  [P0960R3 Allow initializing aggregates from a parenthesized list of values](https://wg21.link/P0960R3)|No|

|  [P1002R1 try-catch blocks in constexpr functions](https://wg21.link/P1002R1)|No|

|  [P1064R0 Allowing virtual function calls in constant expressions](https://wg21.link/P1064R0)|No|

|  [P1073R3 Immediate functions](https://wg21.link/P1073R3)|No|

|  [P1084R2 Today's return-type-requirements are insufficient](https://wg21.link/P1084R2)|No|

|Feature Area| |

|---|---|

|__C++20 Standard Library Features__|__Supported__|

|  [P0019R8 atomic_ref](https://wg21.link/P0019R8)|No|

|&nbsp;&nbsp;[P0020R6 atomic\<float>, atomic\<double>, atomic\<long double>](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0020r6.html)|No|

|&nbsp;&nbsp;[P0053R7 \<syncstream>](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0053r7.pdf)<br/>&nbsp;&nbsp;[P0753R2 osyncstream Manipulators](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0753r2.pdf)|No|

|&nbsp;&nbsp;[P0122R7 \<span>](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0122r7.pdf)|No|

|&nbsp;&nbsp;[P0202R3 constexpr For \<algorithm> And exchange()](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0202r3.html)|No|

|&nbsp;&nbsp;[P0339R6 polymorphic_allocator<>](https://wg21.link/P0339R6)|No|

|&nbsp;&nbsp;[P0340R3 SFINAE-Friendly underlying_type](https://wg21.link/P0340R3)|No|

|&nbsp;&nbsp;[P0355R7 \<chrono> Calendars And Time Zones](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0355r7.html)|No|

|&nbsp;&nbsp;[P0356R5 bind_front()](https://wg21.link/P0356R5)|No|

|&nbsp;&nbsp;[P0357R3 Supporting Incomplete Types In reference_wrapper](https://wg21.link/P0357R3)|No|

|&nbsp;&nbsp;[P0415R1 constexpr For \<complex> (Again)](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0415r1.html)|No|

|&nbsp;&nbsp;[P0439R0 enum class memory_order](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0439r0.html)|No|

|&nbsp;&nbsp;[P0463R1 endian](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0463r1.html)|No|

|&nbsp;&nbsp;[P0475R1 Guaranteed Copy Elision For Piecewise Construction](https://wg21.link/P0475R1)|No|

|&nbsp;&nbsp;[P0476R2 <bit> bit_cast](https://wg21.link/P0476R2)|No|

|&nbsp;&nbsp;[P0482R6 char8_t: A type for UTF-8 characters and strings](https://wg21.link/P0482R6)|No|

|&nbsp;&nbsp;[P0487R1 Fixing operator>>(basic_istream&, CharT*)](https://wg21.link/P0487R1)|No|

|&nbsp;&nbsp;[P0528R3 Atomic Compare-And-Exchange With Padding Bits](https://wg21.link/P0528R3)|No|

|&nbsp;&nbsp;[P0556R3 <bit> ispow2(), ceil2(), floor2(), log2p1()](https://wg21.link/P0556R3)|No|

|&nbsp;&nbsp;[P0591R4 Utility Functions For Uses-Allocator Construction](https://wg21.link/P0591R4)|No|

|&nbsp;&nbsp;[P0600R1 \[\[nodiscard\]\] For The STL, Part 1](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0600r1.pdf)|No|

|&nbsp;&nbsp;[P0608R3 Improving variant's Converting Constructor/Assignment](https://wg21.link/P0608R3)|No|

|&nbsp;&nbsp;[P0616R0 Using move() In \<numeric>](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0616r0.pdf)|No|

|&nbsp;&nbsp;[P0619R4 Removing C++17-Deprecated Features In C++20](https://wg21.link/P0619R4)|No|

|&nbsp;&nbsp;[P0653R2 to_address()](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0653r2.html)|No|

|&nbsp;&nbsp;[P0655R1 visit<R>()](https://wg21.link/P0655R1)|No|

|&nbsp;&nbsp;[P0674R1 make_shared() For Arrays](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0674r1.html)|No|

|&nbsp;&nbsp;[P0758R1 is_nothrow_convertible](https://wg21.link/P0758R1)|No|

|&nbsp;&nbsp;[P0767R1 Deprecating is_pod](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0767r1.html)|No|

|&nbsp;&nbsp;[P0768R1 Library Support For The Spaceship Comparison Operator \<=>](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0768r1.pdf)|No|

|&nbsp;&nbsp;[P0771R1 noexcept For std::function's Move Constructor](https://wg21.link/P0771R1)|No|

|&nbsp;&nbsp;[P0811R3 midpoint(), lerp()](https://wg21.link/P0811R3)|No|

|&nbsp;&nbsp;[P0879R0 constexpr For Swapping Functions](https://wg21.link/P0879R0)|No|

|&nbsp;&nbsp;[P0896R4 \<ranges\>](https://wg21.link/P0896R4)|No|

|&nbsp;&nbsp;[P0898R3 Standard Library Concepts](https://wg21.link/P0898R3)|No|

|&nbsp;&nbsp;[P0912R5 Library Support For Coroutines](https://wg21.link/P0912R5)|No|

|&nbsp;&nbsp;[P1020R1 Smart Pointer Creation With Default Initialization](https://wg21.link/P1020R1)|No|

|&nbsp;&nbsp;[P1023R0 constexpr For std::array Comparisons](https://wg21.link/P1023R0)|No|

|&nbsp;&nbsp;[P1032R1 Miscellaneous constexpr](https://wg21.link/P1032R1)|No|

|&nbsp;&nbsp;[P1165R1 Consistently Propagating Stateful Allocators In basic_string's operator+()](https://wg21.link/P1165R1)|No|

|&nbsp;&nbsp;[P1209R0 erase_if(), erase()](https://wg21.link/P1209R0)|No|

|&nbsp;&nbsp;[P1227R2 Signed std::ssize(), Unsigned span::size()](https://wg21.link/P1227R2)|No|

|&nbsp;&nbsp;[P0185R1 is_swappable, is_nothrow_swappable](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0185r1.html)|VS 2015.3|

|&nbsp;&nbsp;[P0209R2 make_from_tuple()](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0209r2.pdf)|VS 2017 15.0|

|&nbsp;&nbsp;[P0218R1 \<filesystem>](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0218r1.html)<br/>&nbsp;&nbsp;[P0219R1 Relative Paths For Filesystem](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0219r1.html)<br/>&nbsp;&nbsp;[P0317R1 Directory Entry Caching For Filesystem](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0317r1.html)<br/>&nbsp;&nbsp;[P0392R0 Supporting string_view In Filesystem Paths](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0392r0.pdf)<br/>&nbsp;&nbsp;[P0430R2 Supporting Non-POSIX Filesystems](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0430r2.pdf)<br/>&nbsp;&nbsp;[P0492R2 Resolving NB Comments for Filesystem](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0492r2.html)|VS 2017 15.7 ^[E](#note_E)|

|&nbsp;&nbsp;[P0226R1 Mathematical Special Functions](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0226r1.pdf)|VS 2017 15.7|

|&nbsp;&nbsp;[P0254R2 Integrating string_view And std::string](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0254r2.pdf)|VS 2017 15.0|

|&nbsp;&nbsp;[P0258R2 has_unique_object_representations](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0258r2.html)|VS 2017 15.3 ^[G](#note_G)|

<a name="note_E"></a>__E__ This is a completely new implementation, incompatible with the

previous `std::experimental` version, necessitated by symlink support, bug fixes, and changes in standard-required behavior. Currently, including \<filesystem> provides the new `std::filesystem` and the previous `std::experimental::filesystem`, and including \<experimental/filesystem> provides only the old experimental implementation. The experimental implementation will be REMOVED in the next ABI-breaking release of the libraries.

<a name="note_G"></a>__G__ Supported by a compiler intrinsic.

<a name="note_14"></a>__14__ These C++17/20 features are always enabled, even when [/std:c++14](../build/reference/std-specify-language-standard-version.md) (the default) is specified. This 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 [/std:c++latest](../build/reference/std-specify-language-standard-version.md)) compiler option.

<a name="note_byte"></a>__byte__ `std::byte` is enabled by [/std:c++17](../build/reference/std-specify-language-standard-version.md) (or [/std:c++latest](../build/reference/std-specify-language-standard-version.md)), but because it can conflict with the Windows SDK headers in some cases, it has a fine-grained opt-out macro. It can be disabled by defining `_HAS_STD_BYTE` as `0`.