See also / Zc:preprocessor documentation]( )įor Visual Studio changes (beyond the C++ toolset) and download links, see the VS Release Notes and VS Preview Release Notes. Named Modules do not require this option.
See /permissive- documentation regarding compiling code under `/permissive-`.įor code that previously compiled under / std:c ++latest and requires non-conformant compiler behaviors, `/permissive` may be specified to turn off strict conformance mode in the compiler and must appear after / std:c ++latest in the command line argument list. Strict conformance mode (/permissive-) and / std:c ++latestĪs a prerequisite for Modules support, `/permissive-` is now enabled when / std:c ++latest is specified. Two of the major features of C++20, Modules and Coroutines, are now feature-complete in the MSVC toolset and are now implied by the / std:c ++latest compiler switch. Implemented P1874R1 Dynamic Initialization Order of Non-Local Variables in Modules.Implemented P1975R0 Fixing the wording of parenthesized aggregate-initialization.Implemented P1766R1 Mitigating minor modules maladies.Implemented P1811R0 Relaxing redefinition restrictions for re-exportation robustness.Implemented P0848R3 Conditionally trivial special member functions.Implemented P0960R3 Allow initializing aggregates from a parenthesized list of values.Implemented P0315R4 Allowing lambdas in unevaluated contexts.VS 2019 v 16.8 C++20 Language Feature Support Implemented US212 Converting from T* to bool should be considered narrowing.Implemented CWG 2282 Consistency with mismatched aligned/non-over-aligned allocation/deallocation functions.Implemented CWG 2441 Inline function parameters.Implemented CWG 2382 Array allocation overhead for non-allocating placement new.Implemented CWG 2280 Matching a usual deallocation function with placement new.
Implemented P1972R0 US105 Check satisfaction of constraints for non-templates….Implemented P1814R0 CTAD for alias templates.Implemented P1152R4 Deprecating volatile.Implemented P1452R2 On the non-uniform semantics of return-type-requirements.Implemented P0388R4 Permit conversions to arrays of unknown bound.Implemented P1816R0 CTAD for aggregates.Implemented P1331R2 Permitting trivial default initialization in constexpr contexts.Implemented P1094R2 Nested inline namespaces.Implemented P0722R3 Efficient sized delete for variable sized classes.Implemented P1009R2 Array size deduction in new-expressions.VS 2019 v16.7 C++20 Language Feature Support
Īs a reminder, the / std:c ++17 and / std:c ++latest compiler options are necessary to use C++17 and C++20 features, respectively. Some of the features covered were already highlighted in the announcements made a t CppCon 2020 in September related to the VS 2019 v16.8 Preview 3 release. The changelog for conformance progress for the STL is tracked in the Standard Library changelog in the Microsoft STL GitHub repo. This blog post will specifically focus on language features implemented in the MSVC compiler (cl.exe). This blog post lists the features implemented since the C++20 Features and Fixes in VS 2019 16.1 through 16.6 blog post. We have continued our efforts to implement C++20 in the MSVC toolset, with noteworthy progress being made in VS (Visual Studio) 2019 v16.7 and VS 2019 v16.8.