{"id":35467,"date":"2025-05-13T17:27:47","date_gmt":"2025-05-13T17:27:47","guid":{"rendered":"https:\/\/devblogs.microsoft.com\/cppblog\/?p=35467"},"modified":"2025-05-14T08:31:37","modified_gmt":"2025-05-14T08:31:37","slug":"whats-new-for-cpp-developers-in-visual-studio-2022-17-14","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/cppblog\/whats-new-for-cpp-developers-in-visual-studio-2022-17-14\/","title":{"rendered":"What\u2019s New for C++ Developers in Visual Studio 2022 17.14"},"content":{"rendered":"

Visual Studio 2022 version 17.14 is now generally available! This post summarizes the new features you can find in this release for C++. You can download Visual Studio 2022 from the Visual Studio downloads page\u00a0<\/a>or upgrade your existing installation by following the\u00a0Update Visual Studio Learn page<\/a>.<\/p>\n

Standard Library and Compiler<\/h2>\n

We\u2019ve made a myriad of fixes and improvements to the MSVC compiler and standard library. See C++ Language Updates in MSVC in Visual Studio 2022 17.14 <\/a>for a full list of changes on the compiler side, and the STL Changelog<\/a> for all the standard library updates.<\/p>\n

Compiler<\/h3>\n

We\u2019ve added support for several C++23 features, which are available under the \/std:c++latest<\/code> and \/std:c++23preview<\/code> flags.<\/p>\n

You can now omit ()<\/code> in some forms of lambdas that previously required them, thanks to P1102R2<\/a>:<\/p>\n

auto lambda = [] constexpr { }; \/\/no '()' needed after the capture list<\/code><\/pre>\n
We implemented if consteval<\/a><\/code>, with which you can run different code depending on whether the statement is executed at compile time or run time. This is useful for cases where your run time version can be heavily optimized with compiler intrinsics or inline assembly that are not available at compile time:<\/p>\n
constexpr size_t strlen(char const* s) {\r\n    if consteval {\r\n        \/\/ if executed at compile time, use a constexpr-friendly algorithm\r\n        for (const char *p = s; ; ++p) {\r\n            if (*p == '\\0') {\r\n                return static_cast<std::size_t>(p - s);\r\n            }\r\n        }\r\n    } else {\r\n        \/\/ if executed at run time, use inline assembly\r\n        __asm__(\"SSE 4.2 magic\");\r\n    }\r\n}\r\n<\/code><\/pre>\n
We now support attributes for lambdas<\/a>:<\/p>\n
auto lambda = [] [[nodiscard]] [[deprecated]] { return 10; };\r\n\r\nvoid f() {\r\n    lambda(); \/\/ fires a deprecation warning and a discard of return value warning.\r\n}<\/code><\/pre>\n
We also now support static operator()<\/a><\/code> and static operator[]<\/a><\/code>. These allow the compiler to generate more efficient code for these operators when the implicit object parameter is not needed and therefore does not need to be passed as an argument to the function:<\/p>\n
struct X {\r\n    static bool operator()(int) const;\r\n};\r\n\r\ninline constexpr X x;\r\n\r\nint count_x(std::vector<int> const& xs) {\r\n    return std::count_if(xs.begin(), xs.end(), x);\r\n}<\/code><\/pre>\n
The performance of generated code improved due to 17.14 including earlier SSA optimizations and control-flow simplifications. The 17.14 compiler emits 20% faster code than the initial Visual Studio 2022 17 release.<\/p>\n
For throughput, the 17.14 compiler incorporates a dataflow simplification that reduced the compile time of an UnrealEngine \/LTCG<\/code> link repro by 13%.<\/p>\n
Standard Library<\/h3>\n
We have implemented parts of standard library hardening<\/a>, which checks for some instances of undefined behavior at runtime and reports them to the user. This is currently disabled by default, but you can enable it by defining _MSVC_STL_HARDENING<\/code> to 1 project-wide. The proposal uses C++26 contract violations as the mechanism for reporting hardened precondition violations, but since we haven\u2019t implemented contracts yet, we default to calling __fastfail()<\/code>.<\/p>\n
Another new safety feature we have added is destructor tombstones, which help mitigate use-after-free mistakes. This is also disabled by default, but can be enabled by defining _MSVC_STL_DESTRUCTOR_TOMBSTONES<\/code> to 1 project-wide.<\/p>\n
Some miscellaneous improvements we have made are:<\/p>\n