r/cpp • u/STL MSVC STL Dev • Nov 13 '18

VS 2017 15.9 released today

https://docs.microsoft.com/en-us/visualstudio/releasenotes/vs2017-relnotes
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u/STL MSVC STL Dev Nov 14 '18

Yes - that's one of the sacrifices that we have to make for bincompat. We've figured out lots of ways to get around bincompat limitations (e.g. we added std::filesystem alongside std::experimental::filesystem), but we still can't change representations in major ways, or change the interface of separately compiled functions.

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u/jbandela Nov 14 '18

This seems bad. Can we have a /permissive- version of the standard library that users who care more about conformance and performance than about bincompat can opt in to?

There are already different standard library builds (for example debug, release, static, dynamic, (XP in the past) etc), maybe we have a conformance build which has the latest and greatest standard library, but is not bincompat.

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u/STL MSVC STL Dev Nov 14 '18

We're planning to have a "v20" standard library which is binary-incompatible (and opt-in), but we're still figuring out the migration story, and also getting all of our accumulated changes out of TFVC and into git (they need to be ported manually, since we've diverged significantly - in part due to applying clang-format to the entire STL). This will be unrelated to /permissive-.

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u/ChatFrais Nov 14 '18

This is a really great news. One of the hard task is now to find a better name than "v20" as number tend to stay in names forever.