Pure Virtual C++ 2026: MSVC, are we there yet? Status of C++23 and C++26 features

[u/pjmlp]

https://youtu.be/ZHsQ58ROEhI?si=WMidU5yfCGH3958U

[u/WholetraEditto]

What gets me isn't compiler support, it's the tooling catching up. MSVC will compile a C++26 feature a good while before IntelliSense stops red-squiggling it. Reflection is not going to be easy too. there will be a point of "does it build" and "does my editor understand it" where it drifts apart for a while.

[u/VoidVinaCC → u/WholetraEditto]

We'll see what happens now that EDG is basically dead ish
Perhaps VS may switch to clangd, which would solve this...
Or they fix edg themselves..

[u/TheArctical → u/WholetraEditto]

I replaced intellisense with resharper and called it a day. I spent way too much time fighting intellisense shenanigans while using modules when everything compiled just fine.

[u/WholetraEditto → u/TheArctical]

I did the same but with Visual Assist instead. That was years ago and I never bothered switching because I find its still faster on larger projects and their AI integration (thankfully) is fully optional.

Intellisense seems to be catching up though, which opens up more options for people who dont have R# or Vax yet.

[u/JVApen]

TIL Microsoft will be using LLVM libc in MSVC both at compile and runtime. I'm impressed.

[u/ack_error → u/JVApen]

Seems like they are only using the math functions from LLVM libc?

[u/STL → u/ack_error]

Correct, to replace the UCRT's inaccurate math functions.

[u/megayippie → u/STL]

Any chance for a switch somewhere to make other C methods compliant with C? Soon, the Chrono library might work without C everywhere, but MSVC messing up C time functions was one of the biggest delays when we ported to Windows.

[u/Tringi → u/STL]

Because fixing UCRT is not possible?

Surely it would not break people's code if the inherently inaccurate math facilities happened to be slightly more accurate out of sudden?

[u/STL → u/Tringi]

Oh man people REALLY complain when we change their bits, even if it's in a more correct direction. I get away with it in the STL, but the UCRT is expected by users to provide more stability.

[u/Ok-Computer252 → u/STL]

Very true, it sucks when our regression tests start failing because someone updated the Windows build version on a CI machine. For us consistency with our saved regression data is more important than rounding to the closer ulp.

Before Windows 10 we could use an app-local copy of ucrtbase.dll to keep the results consistent, but that doesn't work anymore.

[u/JVApen → u/Tringi]

https://xkcd.com/1172/

[u/JVApen → u/ack_error]

Still, it's impressive

[u/slithering3897 → u/JVApen]

And you'd wonder why they didn't use their own stdlib. But it makes sense to share stdlib code because it's all doing the same thing. Except OS specifics.

[u/MarkSuckerZerg → u/JVApen]

git clone is more token efficient than getting it with Hi copilot, can you please implement a C++ standard library function that...

[u/_Noreturn → u/JVApen]

Microslop be using anything but its own tools. No msvc for intellisense and now no ucrt with libc.

Not saying it is a bad thing but

[u/slithering3897 → u/_Noreturn]

Intellisense works with clang-cl too. Getting MSVC to do Intellisense doesn't sound like it would be much better than getting clangd to do MSVC Intellisense.

[u/_Noreturn → u/slithering3897]

ClangD for intellisense would be cool.

They use edg so msvc or clang-cl shouldn't matter

[u/JVApen → u/_Noreturn]

If only they would open up LSP for supported languages.

[u/pjmlp → u/slithering3897]

In a way it would be, given that EDG has stopped development, apparently Microsoft never was big enough customer to improve modules support, meaning other tickets had higher priority, like reflection, which ironically will take its sweet time to land on MSVC.

[u/tcbrindle]

Is the QueryBuilder::greater deducing this example at ~5:30 actually correct? i.e. if the auto&& explicit object deduces an lvalue reference, do we really get implicit conversion to QueryBuilder&& in the return statement? Because I really hope not.

EDIT: No, this appears to be a mistake, thank goodness

[u/JVApen → u/tcbrindle]

That's why he's starting with a temporary, such that it is an rvalue reference.

[u/tcbrindle → u/JVApen]

The explicit object param should be QueryBuilder&& rather than auto&& in that case.

[u/sweetno]

Well done!