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Comment by webaholic | Hacker News Reader

Congratulations! Clang is almost there too (http://clang.llvm.org/cxx_status.html).

I love seeing free compilers get advanced features years ahead of proprietary compilers like MSVC and Intel Studio.

The folks working on the Microsoft compiler have done a fantastic job lately keeping up with features, so I wouldn't call them years behind.

https://blogs.msdn.microsoft.com/vcblog/2016/01/22/vs-2015-u...

Please see the history behind 'SFINAE' for what I am talking about.

Is it fair to dismiss them for something that old? This is a thread about C++17, and Microsoft has shown themselves to be a great participant in pushing modern C++ forward and encouraging adoption; see: GoingNative, cppcon.

The point being discussed is the availability of modern c++ features in MSVC, not their participation.

The level of coordination here in the C++ space is astonishing and commendable. This stuff used to take over a decade to trickle in and now it's all falling into place right on schedule.

It's quite amazing to see the degree of change; unfortunately, as C++ compilers are so integral to the system, shipping newer code for older platforms is proving quite difficult. We recently went to C++11 and have to drop binary builds (through OBS and PPA) for a number of still-maintained but older platforms, sadly.

Shame there isn't a 'C' target for modern C++ compilers.

Sure, I like many of the new features of C++ that could be compatible with or adapted to C (constexpr, auto, typed enums, or even (gasp).. templates for generic programming) and I'm jealous of the level of innovation in C++ (which would't be that difficult to backport to C since the features already are on C++), especially for embedded.

Why wouldn't you just use c++ then? Almost all c++ is valid C, no?

A lot of people write C in C++ mode just for convenience, you get things like const, but it's not the same as writing actual standards compliant C code.

If you need portable C code, forget about all that stuff. Forget about a lot of things since some compilers are truly atrocious.

Almost all C is valid C++, but the reverse isn't true.

Almost but not all. Restrict keyword, by example.

Also modern features like atomics and complex numbers are implemented as language features in C, but with template libraries in C++. Likewise type-generic math in C11 uses the C-specific _Generic keyword, but uses templates and function overloading in C++

Didn't there used to be an LLVM C backend?

I think it's long since fallen into disrepair/bitrot, but it could probably be revived if there was enough demand.

Oh! I looked a bit and found https://github.com/JuliaComputing/llvm-cbe, with its last commit a month ago.

Thanks! This really should've been kept first class part of LLVM. It'd be a handy way to compile rust to various MCU architecture that llvm doesn't directly support.

This sounds like it's more of a library thing than language thing. The problem (I'm guessing) is the older platforms have `libstdc++` which won't support newer features* . Though I suspect statically linking `libstdc++` might be a (nasty, but workable) option here.

* - again, I'm guessing - I've been out of the c++ game for a few years...

For those wondering,

OBS: https://en.wikipedia.org/wiki/Open_Build_Service

PPA: https://en.wikipedia.org/wiki/Personal_Package_Archive

One reason people started looking into alternative languages was the small pace the C++ compilers were moving. It was hard to be excited about new language features when you knew no one would implement in near future (near being 5-10 years).

It is great to see that things have changed.

Especially compared to when VS is getting complete support for C99; which IIRC is sometime between when the sun stops burning and the heat death of the universe.

I would be nice if people realized how actually MSVC and Intel Studio are in regards to other commercial vendors.

http://en.cppreference.com/w/cpp/compiler_support

And the embedded ones like TI are even behind those.

I would also guess that it might not be good business to publish experimental features from a standard that doesn't exist yet. I think Microsoft is already implementing these features, they are just not out yet.

https://blogs.msdn.microsoft.com/vcblog/2016/11/16/permissiv...

> The Visual C++ Team is excited to announce that the compiler in Visual Studio 2017 RC will feature a mode much closer to ISO C++ standards conformance than any time in its history. This represents a major milestone in our journey to full ISO C++ conformance. The mode is available now as an opt-in via the /permissive- switch but will one day become the default mode for the Visual C++ compiler.

I'm really excited about having MS right up at the front of the pack with GCC and Clang.

"much closer"? I look forward to their new compiler bugs.

Really? They make progress and all you we any to do is trash talk their efforts?

The strange vagueness in stating they are "close" means the Microsoft C++ compiler team know they still miss shamefully important pieces, with the necessary consequence that optimistic users expecting C++17 will be bitten by unexpected significant compiler bugs. They should be more open.

I respect the progress Microsoft is making, both in the long term (since the dark ages in which they didn't care about standards) and in the short term (a genuine C++17 implementation effort), but their progress is still slower than the competition.

Not when we take into consideration the C++ commercial vendors as part of the competition pool.

Intel also usually releases a beta every year with all the new features bunched together. They don't tend to push features out in frequent incremental updates instead opting for yearly releases with bugfixes in point releases in between.

I love the work being done by the clang and gcc teams, but I still stick with Intel's C++ compiler for many things due to its far better support for automatic vectorization among other things.

N4086: the future is now!

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