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Re:C++ Core Coroutines Proposal [pdf] by cjhanks on Friday September 21, 2018 @12:53AM (#18037233)
The rapid change in C++ syntax may destabilize it.

For example; `auto OpenFile(const string& filename) using future_coroutine<File> [filename]`. Okay, I get it. Or the operator `[<-]`.

But as the idioms find their way into production code - an entire important segment of the C++ developer base is going to no longer be capable of reading the language. And that might be worse than not having features.

Re:C++ Core Coroutines Proposal [pdf] by hfdgiutdryg on Friday September 21, 2018 @01:40AM (#18037395)
I spent a decade watching C++ painfully slowly add more advanced template support and... well, that's about it. After a million iterations of "for (mylisttype::const_iterator i ..." they finally added ranged for loops.

The rate of change seems to be increasing. This is initially a bit shocking until I remember that every single job I had was like using a completely different language because, even ten years ago, every shop used a different subset of C++ and STL!

Add all you want to the language, it's all going to devolve into code-review infighting the same way it did in 2008.

Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @02:45AM (#18037628)
This is a common complaint about C++, as if the other languages were any better in this regard.

Java 11, C# 8, Python 3.7, Fortran 2018, F# 4.5,.... try to write in a way that everyone will agree with, or do language quiz to see what which one gets right.

Sure there is C that looks so simple, who gets right all the ISO C changes between C89, C90, C11, C17, UB and compiler specific extensions/issues without having to look into the books?

Re:C++ Core Coroutines Proposal [pdf] by gpderetta on Friday September 21, 2018 @06:01AM (#18038495)
> I spent a decade watching C++ painfully slowly add more advanced template support and... well, that's about it. After a million iterations of "for (mylisttype::const_iterator i ..." they finally added ranged for loops.

C++ was first standardized in '98. Nothing happened for more 10 year (in particular no new advanced template support) unless you count the very minor bug fixes in C++03. The next revision, C++11, added ranged for loops.

Re:C++ Core Coroutines Proposal [pdf] by hfdgiutdryg on Friday September 21, 2018 @08:51AM (#18039293)
Compilers don't strictly adhere to standards, and I'm far more concerned with things like whether my compiler crashes, how godawful the error messages are, and whether the bundled STL even functions reliably.
Re:C++ Core Coroutines Proposal [pdf] by cjhanks on Friday September 21, 2018 @10:45PM (#18044171)
Haha, you're too crusty to be listened to!

Yeah, you're right. In some respects, things haven't changed.

Re:C++ Core Coroutines Proposal [pdf] by eecc on Friday September 21, 2018 @03:27AM (#18037809)
Hah, those code reviews must be fun. At least as much as a Scala one ;)
Re:C++ Core Coroutines Proposal [pdf] by 01100011 on Friday September 21, 2018 @01:13AM (#18037300)
If I understand things correctly, the C++ people are attempting to modernize the language and add a bunch of new stuff with the intention of deprecating the old stuff. They're constrained by legacy cruft so the new features end up with rather ugly syntax. I applaud their efforts but frankly I'd rather see a new language done right.

I'm currently trying to modernize my C++ skills and while I love some of the new features I think they're creating an inconsistent, ugly, beast of a language.

Re:C++ Core Coroutines Proposal [pdf] by wvenable on Friday September 21, 2018 @01:40AM (#18037394)
C++ will always have a place because it's a language that literally has (or will have) everything. I've used features of C++ that have no analogy in other languages. If I designed a language tomorrow, I wouldn't put that feature in. Too obscure. But I needed this random feature for a project on a constrained device to do C callback trampolines to C++ object methods.

When it comes to C++, there is no magic alternative that is "done right". I think that Rust may be the closest C++ alternative that will get in our lifetime and it's syntax isn't exactly non-ugly either.

Re:C++ Core Coroutines Proposal [pdf] by mschuetz on Friday September 21, 2018 @03:04AM (#18037712)
It has far from "literally" everything. It doesn't have async/await, doesn't have a sane way to create simple web servers, doesn't have map/find/filter/etc on collections, at least not a version that won't span multiple lines or the whole screen because they require mandatory arguments (begin, end) that are useless 99% of the time because you want to operate on the whole collection anyway, etc.
Re:C++ Core Coroutines Proposal [pdf] by geezerjay on Friday September 21, 2018 @03:17AM (#18037762)
> It doesn't have async/await,

That's just a C# idiom, and far from being the right or sane way to handle concurrency.

Meanwhile C++ has active objects and futures and other concurrency design patterns.

> doesn't have a sane way to create simple web servers

Check POCO.

> doesn't have map/find/filter/etc on collections, at least not a version that won't span multiple lines or the whole screen because they require mandatory arguments (begin, end) that are useless 99% of the time because you want to operate on the whole collection anyway, etc.

That's a very silly complaint. You acknowledge that C++ does have map/find/filter (which at this stage is rather obvious to anyone who ever used C++) but somehow you're complaining that C++'s interfaces require programmers to specify where the collections should start and finnish.

Re:C++ Core Coroutines Proposal [pdf] by vardump on Friday September 21, 2018 @04:18AM (#18038039)
> but somehow you're complaining that C++'s interfaces require programmers to specify where the collections should start and finnish.

I think it is a valid complaint. Most of time you want to apply something like "find" to the whole collection.

I'd also love to have C++ standard maps (esp. unordered_map) where I only pay for what I use. Namely, due to C++ spec I have to pay for the nodes instead of having a flat, CPU cache efficient, buffer. In other words, a different map type where other items are allowed to move in memory when something is inserted or removed.

Oh, while we're at it, it'd be nice if vectors etc. could realloc instead of allocating a completely new memory region and freeing the old one when more space is required.

A more ergonomic allocator story for specifying alternative allocators would also be very nice for some niches, like when you need to avoid fragmentation or require better performance in embedded development.

Re:C++ Core Coroutines Proposal [pdf] by jcelerier on Friday September 21, 2018 @06:07AM (#18038526)
> I think it is a valid complaint. Most of time you want to apply something like "find" to the whole collection.

frankly, this is a very overstated problem. It's trivial to write a header with such functions (e.g. https://github.com/OSSIA/libossia/blob/master/OSSIA/ossia/de...). And it's already provided by Boost if you use it.

Re:C++ Core Coroutines Proposal [pdf] by vardump on Friday September 21, 2018 @08:44AM (#18039258)
Yeah, it's trivial to do that.

But since it's not in STL, everyone will use a bit different implementations for something this mundane and common.

Re:C++ Core Coroutines Proposal [pdf] by wsy on Friday September 21, 2018 @12:14PM (#18040729)
I'd rather say, (mostly) everybody will use Boost.
Re:C++ Core Coroutines Proposal [pdf] by pas on Saturday September 22, 2018 @06:33AM (#18045406)
Or folly. Or something else. Which leads to the awful package management story. (Maybe modules will help.)
Re:C++ Core Coroutines Proposal [pdf] by michal_f on Friday September 21, 2018 @08:24AM (#18039158)
Re:C++ Core Coroutines Proposal [pdf] by BurnGpuBurn on Friday September 21, 2018 @04:47AM (#18038158)
Memory allocation by STL has been broken for as long as I remember, which is at least twelve years or so. It's been a while but if I remember correctly it doubled its allocation every time it ran out or space.
Re:C++ Core Coroutines Proposal [pdf] by jcelerier on Friday September 21, 2018 @06:06AM (#18038518)
> It's been a while but if I remember correctly it doubled its allocation every time it ran out or space.

why would you call this "broken" ? That's one of the most optimal solutions for reallocations if you append values continuously, since it will reallocate only logarithmically.

Re:C++ Core Coroutines Proposal [pdf] by EpicEng on Friday September 21, 2018 @11:31AM (#18040417)
Which libs _don't_ use that allocation strategy? The fact that you think it's broken only means you don't really know what you're talking about.
Re:C++ Core Coroutines Proposal [pdf] by gmadsen on Friday September 21, 2018 @07:28AM (#18038883)
what? ha, that is the text book approach to reallocating an array for additional values to get log complexity
Re:C++ Core Coroutines Proposal [pdf] by vardump on Friday September 21, 2018 @08:01AM (#18039035)
I'm not so sure I'd want a 2GB vector to grow to 4GB, etc.
Re:C++ Core Coroutines Proposal [pdf] by ChrisSD on Friday September 21, 2018 @08:29AM (#18039182)
In such extreme cases you can (and should) use your own allocation strategy.
Re:C++ Core Coroutines Proposal [pdf] by vardump on Friday September 21, 2018 @08:41AM (#18039234)
Yeah, but I'm not entirely clear how I'd for example get std::vector to use a mmap'ed range, that I could zero-copy grow.

Also in that case I might want to grow it by a fixed amount, once it grows past a certain threshold.

It's a shame one needs to write another vector implementation just for that.

Re:C++ Core Coroutines Proposal [pdf] by ChrisSD on Friday September 21, 2018 @08:46AM (#18039266)
Why wouldn't writing an allocator class be enough for mmap?
Re:C++ Core Coroutines Proposal [pdf] by BeeOnRope on Friday September 21, 2018 @12:21PM (#18040769)
Probably not, because the allocators don't expose the "extend" or "realloc" concept, so all you'll see from within your allocator is a request for an entire new region that vector wants in order to copy the new stuff into.

To implement a growing allocation , you'll have to create a custom vector, pretty much.

Re:C++ Core Coroutines Proposal [pdf] by Timmah on Friday September 21, 2018 @12:19PM (#18040755)
How would you ensure nothing was used in the region after the original allocation?
Re:C++ Core Coroutines Proposal [pdf] by dbaupp on Friday September 21, 2018 @08:21AM (#18039142)
O(n^2) time for n push_back calls would be worse, so some sort of multiplication/exponential growth is required for the "fits all" default vector and its default growth strategy.
Re:C++ Core Coroutines Proposal [pdf] by BeeOnRope on Friday September 21, 2018 @12:23PM (#18040783)
Old versions of MSVC used a 3/2 growth factor which led to less extreme jumps for large vectors, although also a lot more copies when filling a small vector. I'm not sure if that's still true.
Re:C++ Core Coroutines Proposal [pdf] by jhasse on Friday September 21, 2018 @08:11AM (#18039082)
Why not?
Re:C++ Core Coroutines Proposal [pdf] by mortehu on Friday September 21, 2018 @07:41PM (#18043481)
I think you mean amortized constant complexity, or O(1).
Re:C++ Core Coroutines Proposal [pdf] by NullPrefix on Friday September 21, 2018 @05:21AM (#18038331)
this is implementation specific. Care to tell which compiler are you talking about?
Re:C++ Core Coroutines Proposal [pdf] by mschuetz on Friday September 21, 2018 @06:05AM (#18038514)
> That's just a C# idiom

Not just C#, Python and JS also have it already. And async-await is the first time ever where I've thought that yes, this is a good way to do single-threaded async (event-queue-ish) or even multi-threaded things.

> Check POCO.

Thanks for the hint, I will check it out.

> but somehow you're complaining that C++'s interfaces require programmers to specify where the collections should start and finnish.

Take a look at: http://www.modernescpp.com/index.php/higher-order-functions The c++ functions are unnecesarely verbose compared to other languages.

This

    transform(vec.begin(), vec.end(), vec.begin(),[](int i){
        return i*i;
    });
could be much more readable as

    vec.map([](int i){ 
        return i*i;
    });
Also makes for-of the better choice in my opinion because if you're going to write more code, I'd rather write code that is readable.
Re:C++ Core Coroutines Proposal [pdf] by hhmc on Friday September 21, 2018 @11:41AM (#18040480)
Those examples aren't really the same though. Transform is a free function which operates on anything that satisfies 'ForwardIterator', map would be a member function of the vector class.

Theoretically you could add helper functions to all suitable containers which calls through to transform (I think this is what you're suggesting). But it would feel very heavyweight and add a lot of cruft to the std library.

You could also add your own utlity free function similar to

  template<class T, class F>
  void mymap(T &t, const F &f){
      std::transform(t.begin(), t.end(), t.begin(), f);
  }
Re:C++ Core Coroutines Proposal [pdf] by geezerjay on Friday September 21, 2018 @02:58PM (#18041859)
> could be much more readable as vec.map([](int i){ return i*i; });

That, however, violates the separation of concerns principle by mangling together data structures and algorithms.

Re:C++ Core Coroutines Proposal [pdf] by __s on Friday September 21, 2018 @08:20AM (#18039140)
Rust is also getting async/await
Re:C++ Core Coroutines Proposal [pdf] by steveklabnik on Friday September 21, 2018 @09:01AM (#18039348)
Which de-sugars to generators, which is similar to, but different from, the various C++ coroutine proposals. I haven’t dug into this one yet though...

It’s going to be pretty important for us: http://aturon.github.io/2018/04/24/async-borrowing/

Re:C++ Core Coroutines Proposal [pdf] by BeeOnRope on Friday September 21, 2018 @12:24PM (#18040794)
What you want is ranges v3.
Re:C++ Core Coroutines Proposal [pdf] by aaaaaaaaaab on Friday September 21, 2018 @07:17AM (#18038827)
Re:C++ Core Coroutines Proposal [pdf] by Timmah on Friday September 21, 2018 @12:24PM (#18040796)
That only saves a few characters. And "map" is already a data type in C++. How are you going to explain to a student that ambiguity, that you can "map a vector, but oh yeah map is also this container type" ?

Conceptually, I hate the word "map" to describe a transform. What does a real-world, paper map do? It associates locations drawn on the paper with real-world, physical places. That doesn't have any commonality whatsoever to morphing a group of objects. The term is misused.

Re:C++ Core Coroutines Proposal [pdf] by mschuetz on Saturday September 22, 2018 @01:25PM (#18046892)
It removes enough characters to turn it from unreadable mess to legible code. Point is mainly to remove the 3 completely unnecessary parameters, doesn't matter if it's called transform or map.
Re:C++ Core Coroutines Proposal [pdf] by geezerjay on Friday September 21, 2018 @03:10AM (#18037734)
> C++ will always have a place because it's a language that literally has (or will have) everything.

I don't think that's true at this stage. Nowadays, beyond legacy code, C++ is used mainly in embedded, number-crunching, and cross-platform GUI applicationd, and that's about it. Meanwhile the world has moved on to web services and web apps, where C++ is nowhere to be seen, and other competing lower-level programming languages are starting to eat away C++'s lunch.

Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @05:59AM (#18038482)
Most of my work is done in Java, .NET and JavaScript, C++ is the only native alternative that I can easily plug into all of them when I need native interop.

Go is not an option until they get their story straight with 2.0.

Swift is nice, but really it will never go beyond being an Apple platform language.

Native/Kotlin is doing its baby steps.

D seemed like a nice alternative, but they are such a small community without any big corporation support, that the language might already have lost its opportunity.

Rust would be the best alternative, but it still lacks the tooling integration story regarding IDE, graphical debuggers and OS vendors support.

Yes, no one is doing pure apps anymore in 100% C++, Java and .NET are slowly migrating to bootstrapped runtimes, but the language is not going away for the foreseeable future.

Kids are learning to program on Arduino devices using C++.

Microsoft already has some ongoing Rust projects, but Visual Rust is not yet here.

AAA Games, compilers specially LLVM and GCC, OS, HPC, Fintech, deep learning, GPGPU shaders, GUI composition engines, IoT, medical devices, car infotainment systems, VFX software might be a niche, but it is a very big niche.

One of the good things about polyglot development is that one doesn't need to silo himself/herself as developer X and be worried if language X is suitable for full stack development across all domains of computing.

EDIT: typos

Re:C++ Core Coroutines Proposal [pdf] by therockhead on Friday September 21, 2018 @07:01AM (#18038757)
> Go is not an option until they get their story straight with 2.0

Would you mind expanding on this point? Where I work, we do lot of C++ for the reasons you described but I have started to learn Go to see if its a suitable replacement.

Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @07:44AM (#18038948)
From my point of view, no generics, error handling boilerplate, no real enums (although there is a kind of workaround).

There are other issues regarding tooling, specially for the use cases that I care, like dynamic loading into other platforms (JVM and .NET), GPU programming and graphical debuggers.

So naturally many C++ dev did not felt at home with Go.

https://commandcenter.blogspot.com/2012/06/less-is-exponenti...

Those pain points are the biggest roadmap points on a possible 2.0 version.

https://blog.golang.org/go2draft

Re:C++ Core Coroutines Proposal [pdf] by ahartmetz on Friday September 21, 2018 @05:22AM (#18038336)
C++ (Rust as well) is for high complexity problems that need high performance solutions. It's not just a few narrow application areas. For example, all major HTML and JS engines are also written in C++. I wouldn't call them (just) GUI applications. I bet that all offline renderers for professional CGI are also C++.
Re:C++ Core Coroutines Proposal [pdf] by brobdingnagians on Friday September 21, 2018 @04:40AM (#18038128)
Don't forget high performance games; which is a huge market, highly complex, and very competitive.
Re:C++ Core Coroutines Proposal [pdf] by bayindirh on Friday September 21, 2018 @07:22AM (#18038853)
It's already written, but things require absolute efficiency and high performance, like HPC and ML cannot be done without C++.

I develop some HPC code, and most of them is infeasible without C++.

Other languages' high performance libraries PIL and numPy is written with C & C++.

Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @07:52AM (#18038992)
NVidia GPUs are now designed explicitly for running C++ code efficiently.

CppCon 2017: Olivier Giroux "Designing (New) C++ Hardware”

https://www.youtube.com/watch?v=86seb-iZCnI

Assuming another systems language, e.g. Rust, does indeed replace C++'s use cases, it is still a very long path until it gets this adoption level from hardware vendors.

Re:C++ Core Coroutines Proposal [pdf] by EpicEng on Friday September 21, 2018 @12:26PM (#18040807)
>C++ is used mainly in embedded, number-crunching, and cross-platform GUI

You forgot a couple: your OS, your web server, image and video codecs, and basically any other low-ish level abstraction you rely on. The world isn't built on web apps.

Re:C++ Core Coroutines Proposal [pdf] by snowAbstraction on Friday September 21, 2018 @06:21AM (#18038577)
I agree with you except that there is sizable chunk of back-end code that is using C++ or at least calling it.
Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @02:49AM (#18037648)
Beautiful languages don't get adopted unless there is an OS vendor stating "It is my way or go elsewhere".

The languages with higher success rate are the ones that build on existing code and practices.

Every language with major market adoption is an inconsistent unless one does a language reboot Perl 6/Python 3 style and is willing to push it forward.

Re:C++ Core Coroutines Proposal [pdf] by fpoling on Friday September 21, 2018 @04:29AM (#18038090)
Do you have an example of a beautiful language that adopted due to vendor stance? I cannot call C# beautiful. Perhaps Swift?
Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @04:34AM (#18038105)
I would say C# was quite beautiful in 2001.

And yes, Swift as well.

Kotlin might eventually be another one, depending how the Java story will evolve past Java 8 on Android.

Re:C++ Core Coroutines Proposal [pdf] by jdoege on Monday September 24, 2018 @10:30AM (#18057962)
I don't know about vendor stance, but Elixir feels fairly elegant (better descriptive word than beautiful, I think.)
Re:C++ Core Coroutines Proposal [pdf] by saagarjha on Friday September 21, 2018 @05:24AM (#18038346)
Objective-C?
Re:C++ Core Coroutines Proposal [pdf] by Gibbon1 on Friday September 21, 2018 @02:14AM (#18037519)
> I applaud their efforts but frankly I'd rather see a new language done right.

Opinion of mine is what's needed is robust and performant inter-op, and only then a new dialect that fixes some of the deep legacy problems with the language. At least that would provide a clean migration path.

Re:C++ Core Coroutines Proposal [pdf] by snarfy on Friday September 21, 2018 @01:08AM (#18037279)
They are adding more syntax to reduce syntax. Have you seen the spaceship operator? C++ has jumped the shark. I just want an ABI. Can we get an ABI already?
Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @01:21AM (#18037321)
It is called COM/UWP on Windows.

A C++ ABI requires an OS written in C++, likewise there is no such thing as C ABI per se, rather UNIX ABI, Win32 ABI and so forth.

Re:C++ Core Coroutines Proposal [pdf] by eridius on Friday September 21, 2018 @03:23AM (#18037787)
A C++ ABI does not require an OS written in C++. It just requires all compiler implementations to agree to standardize on a single ABI and enshrine it in a spec that any future implementations must abide by.
Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @03:41AM (#18037892)
A C++ compiler that needs to support multiple distinct ABIs?

One per each platform, plus an additional one, agreed by all these guys? And the list is not 100% compliant, e.g. TI is missing.

https://en.m.wikipedia.org/wiki/List_of_compilers#C++_compil...

Not even C has managed to do it, what people conventionally refer as C ABI is actually the OS ABI.

I still remember having to deal with multiple C ABI on MS-DOS and Windows static libraries.

Re:C++ Core Coroutines Proposal [pdf] by gpderetta on Friday September 21, 2018 @04:53AM (#18038186)
I'm really interested to know how a standard ABI would cover both little endian 32 bit x86 and big endian 64 bit POWER.
Re:C++ Core Coroutines Proposal [pdf] by eridius on Saturday September 22, 2018 @12:59AM (#18044536)
Compilers already have ABIs, they're just compiler-specific and not documented. If they didn't have an ABI, then you couldn't link 2 C++ libraries together.

In terms of having one spec that handles arbitrary architectures, maybe it could be defined relative to the C ABI? I don't actually know how what the internal ABIs used by the current crop of C++ compilers looks like, so I don't know if they could be expressed relative to the C ABI or not.

Alternatively, one could come up with a set of configurable values that define what makes one architecture different from another (such as word size, long/pointer size (if different than word size), endianness, etc). You know, the stuff that the compiler already has to know about in order to compile for an architecture (and I'm pretty sure clang at the least already has a way to even define new target triples in terms of a set of configurable values for this sort of thing). I assume existing compilers don't invent entirely brand new ABIs for each new architecture but instead just adapt an internal standard C++ ABI to the new architecture using a similar process already. The same could be done for a public standard C++ ABI.

Re:C++ Core Coroutines Proposal [pdf] by hfdgiutdryg on Friday September 21, 2018 @01:35AM (#18037375)
Pardon the dumb question, but is the term ABI new (or experiencing a recent increase in usage)? I've seen it twice in the last 24 hours, and never before in my life. And that's despite being entirely too familiar with COM.
Re:C++ Core Coroutines Proposal [pdf] by Elv13 on Friday September 21, 2018 @02:06AM (#18037488)
> but is the term ABI new

No, it is age old. The thing is that it is only "a thing" to embedded native developers and library authors.

The general concept is that the programming language "API" doesn't define how the dll/o/a/la/lib/so/dylib "loader" look for "symbols" in the file. If you example, I do:

    enum {FOO, BAR};
and next month I change it to

    enum {BAZ, FOO, BAR};
then everything will still compile, but if I execute an older program with my library, it still thinks FOO is 0 and BAR is 1 while it's no longer the case. It gets worst for function and type definition. Then when you get into C++, it gets an order of magnitude more complex because almost every code change will somewhat break one or many symbols. This is why there is often "proxies" called PIMPL or d_ptr between the library symbols and the actual implementation code. C++ has no officially standardized way to serialize the object to their symbol names. This is often a pain point and Apple wants to fix this for a decade for has so far failed to get everybody to agree on something.

For embedded devs, more problem arise from the fact that the instruction set and C library themselves are not the same for all devices and this also break pre-compilled code.

Many platform will often favor "static binaries" over dynamic ones to avoid the consequences of breaking the ABI.

Re:C++ Core Coroutines Proposal [pdf] by Gibbon1 on Friday September 21, 2018 @02:24AM (#18037556)
I think you see it because there has be a resurgence in interest in C/C++. probably because people are giving up on the idea that all new languages will run on the JVM.

ABI is ancient since it defines the underlying structure that allows you to link compiled object files and liberals together (the latter both statically and dynamically). Allowing code generated in one module to successfully call functions in another.

Re:C++ Core Coroutines Proposal [pdf] by geezerjay on Friday September 21, 2018 @03:23AM (#18037788)
> Allowing code generated in one module to successfully call functions in another.

That's not quite true. That's already possible without a standard ABI.

What's not possible is to get code compiled by a specific compiler to call modules built by another compiler provided by another vendor. That's the only problem that is addressed by a common ABI.

I would also add that considering MS's interoperability history and how prevalent MSVC++ is, working on a standard ABI would be a waste of time.

Re:C++ Core Coroutines Proposal [pdf] by gpderetta on Friday September 21, 2018 @06:15AM (#18038553)
> What's not possible is to get code compiled by a specific compiler to call modules built by another compiler provided by another vendor. That's the only problem that is addressed by a common ABI.

Yes, compilers need to agree on the ABI, the platform ABI, that is. Today most platforms already have a de-facto or de-jure standard ABI and compilers have the option to implement it.

Even if such a thing was possible, there is no value in the standard committee standardizing an single ABI as most platforms would never break backward compatibility to switch to it.

Re:C++ Core Coroutines Proposal [pdf] by Retra on Friday September 21, 2018 @01:54AM (#18037449)
No, it is an old term.
Re:C++ Core Coroutines Proposal [pdf] by maxxxxx on Friday September 21, 2018 @01:12AM (#18037297)
Yes, an ABI would be great. I am always amazed how easy it is to use libraries in C# or Java whereas C++ is just a PITA.
Re:C++ Core Coroutines Proposal [pdf] by gpderetta on Friday September 21, 2018 @06:21AM (#18038574)
That's possible because all C# and Java compilers only really target a single platform (their respective VM).
Re:C++ Core Coroutines Proposal [pdf] by pjmlp on Friday September 21, 2018 @02:51AM (#18037658)
It is easy as well, when you use a compiler that generates bytecode like C++/CLI.
Re:C++ Core Coroutines Proposal [pdf] by aaaaaaaaaab on Friday September 21, 2018 @03:01AM (#18037702)
Ummmm... Try running java 8 bytecode on an older JVM.