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Comment by astrodust | Hacker News Reader

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.

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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.

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