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I think these are good questions, even if they are off topic.

1. Why doesn’t Go seem to support embedded development. Off the top of my head there is a moderely successful embedded framework, gobot. The reason I don’t think it’s more popular is the runtime. Having any runtime at all tends to be poisonous and running Go without a runtime is difficult because you can’t manage your own memory in Go. Sure you could do a ton of work in making it work, but your effort is better spent just writing your project in Rust.

2. Why doesn’t Go support desktop? This is a case where I just don’t think anyways cares anymore about having good desktop support. You rarely see native desktop applications in anything other than C++ and C#. There are some UI toolkits out there but no one uses them, and something like Electron is used instead. Windows and OS X only give first class support to their blessed languages (C++, .NET, Objective C) and every other language you are out of luck.

I'm curious what you think the primary feature is that makes a Go runtime have to be necessarily large? (If writing a new Go runtime against the specification.)

You mention the need for a runtime, but I don't see that this makes it necessarily huge. For comparison, I'd like to think about using a TinyC compiler[1], called TCC, as a complete runtime to compare against since:

"

* TinyCC (aka TCC) is a small but hyper fast C compiler. Unlike other C compilers, it is meant to be self-relying: you do not need an external assembler or linker because TCC does that for you.

* TCC compiles so fast that even for big projects Makefiles may not be necessary.

* TCC not only supports ANSI C, but also most of the new ISO C99 standard and many GNUC extensions including inline assembly.

"

Now it turns out that the above fits in 100 KB and implements "ANSI C", which for the C89 version is 552 pages or so[2]. The Go specification is 73 pages or so in the same font. (So 13% of the size.) I also think that due to its design the Go language specification and syntax has fewer corner cases.

So clearly there is some "huge" feature that is really holding things back from running on a resource-constrained microcontroller in a stripped-down runtime. What is it?

To see where 100 KB fits (by analogy with TCC above), I looked up some microcontrollers. I first found a popular microcontroller for hobbyists, the ATmega2560 which runs the Arduino Mega. That microcontroller has 56KB ISP flash memory, 8KB SRAM. That RAM is not enough if we take the TinyC executable of around 100 KB as how much is needed. This microcontroller also only costs $6.5 in quantity 1 (unless I misread.)

Moving up a bit in price so we can get at least 128 KB of RAM, a popular choice is something like the AT32UC3A3256[3] which costs $31.25 in an evaluation kit (that gives you an additional 8 MB of RAM), and as far as shipping just the MCU (with its 128KB of RAM only), costs $12 in quantity one. That is a 32-bit device unlike the cheaper Atmega2560 I first mentioned (which is an 8-bit device) so should be easier for people to implement the standard against. The specifications are: 84 MHz, 256 kB program size, 128 kB RAM size.

Why can TCC be 100 KB executable size but independently implementing the Go specification can't?

As for why someone would want to, sure, you're going to be quite constrained, but if someone already knows Go, which had the design goal of being a general-purpose language, why can't they use its syntax for their microcontroller projects?

So what essential feature in the Go specification makes this an absolute non-starter? it's a super small standard.

(As for your second response, about "You rarely see native desktop applications in anything other than C++ ", I read what you wrote but I don't see why the Go ecosystem isn't slowly catching up anyway. It's a great language syntax.)

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[1] https://bellard.org/tcc/ and https://bellard.org/tcc/tcc-doc.html

[2] found a draft here - http://www.open-std.org/JTC1/sc22/wg14/www/docs/n1256.pdf

[3] I found this recommendation here: https://electronics.stackexchange.com/questions/192583/is-th...

> So clearly there is some "huge" feature that is really holding things back from running on a resource-constrained microcontroller in a stripped-down runtime. What is it?

Garbage collection and goroutines. You could probably strip back the implementations a bit but you can't get rid of gc - there is no explicit way of freeing memory. Possibly you could ban the go keyword and run on a single thread, although you'd have to deal with parts of the stdlib that use it.

Java and Oberon fit easily in a ARM Cortex M, which some embedded companies are happily selling, there is no reason why a Go implementation could not exist as well.

It looks like Go implementation exists for ARM Cortex M (based on transpiling Go to C):

https://github.com/ziutek/emgo/blob/master/README.md

https://github.com/ziutek/emgo/issues/14#issuecomment-398670...

https://ziutek.github.io/2018/03/30/go_on_very_small_hardwar...

There is also GERT, but it is for ARMv7a like iMX6 Quad SOC and not updated since one year.

>Garbage collection and goroutines

Do you think the specification is "correct" for a compiled language suitable for embedding?

The word "garbage" is in the specification a single time, in the introduction which says "garbage-collected". I can't see any constrained implementation details thereafter - see for yourself at where I might have missed it:

https://golang.org/ref/spec

The gouroutine section (under the Go keyword) is three paragraphs: "A "go" statement starts the execution of a function call as an independent concurrent thread of control, or goroutine, within the same address space." and "The function value and parameters are evaluated as usual in the calling goroutine, but unlike with a regular call, program execution does not wait for the invoked function to complete. Instead, the function begins executing independently in a new goroutine. When the function terminates, its goroutine also terminates. If the function has any return values, they are discarded when the function completes. "

This does not seem to require the typical accoutrements of the Go compiler. If this is the complete verbiage specifying the behavior of a Goroutine, I could imagine a compliant implementation being lighter-weight than the official Go compiler.

Returning to the idea of GC: the word "memory" appears in the standard 4 times: once mentioning initialization of variables; once on the section on slices ("The built-in functions append and copy assist in common slice operations. For both functions, the result is independent of whether the memory referenced by the arguments overlaps. "); and twice in the last section on system considerations, including light MAY language in "Computer architectures may require memory addresses to be aligned; that is, for addresses of a variable to be a multiple of a factor, the variable's type's alignment. The function Alignof takes an expression denoting a variable of any type and returns the alignment of the (type of the) variable in bytes." and finally under Size and Alignment guarantees, which makes no reference to GC.

If this document is the complete specification, then it seems that the implementer has very wide leeway for how to implement the details of memory management via garbage collection. There doesn't seem to be much language limited behavior.

What do you think?

(In this comment I consider "Go" the language as anything that complies with the Go specification.)

To point 2) I fully agree, Go should be a great choice for desktop applications. One match I think is especially good, that is Gtk based development with Go. Gtk is one of the few UI toolkits which has been designed around a pure C API, so Go is a great match with it. Also, with Gtk the Go applications are reasonably portable to Linux, macOS and Window. I have used Go+Gtk and found it a pleseant experience.

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Firstly, wow! Thanks. Feedback on draft #2.5:

You removed too much praise. Go's syntax is amazing. Can you put that part back in?

(Maybe you removed it because I also called it ugly - as opposed to a beautiful syntax like Python's - but that was not a design goal and doesn't bother me. Nobody meant for Go's syntax to be beautiful.) The summary you got down to "I appreciate Go since" is too weak.

Its syntax is the best of any language on planet Earth, which is why people can write pages of Go that work on first compilation and always do exactly what they imagine. (The second fact that leads to this is that its specifications and feature set is very small, so that it can be kept in mind by the programmer entirely.)

So add stronger praise. If not for such strong praise, why would I want to write everything from desktop applications to microcontroller code in Go, and not any other syntax?

I also have a very strong impression that its syntax and specifications are appropriate for both memory-sensitive applications and for desktop applications. (Not really a question). It is due to this strong impression that I want to know what the impediments are. (Maybe this was not clear.)

I can see no reason why a Go executable can't be made targeting 100 KB of RAM to do its GC and everything else. I also see no reason why bindings against QT or other GUI frameworks aren't made in the Go language syntax - this is a mystery to me. There must be some impediment.

What is it?

Can you reply with another draft that incorporates these?

I greatly appreciate the thoughts you added to the draft. I think Go is the best language syntax for general programming in any environment from a microcontroller with 150 KB of RAM to a major, 2 Gigabyte desktop behemoth's scripting language. I don't think the lack of class system is an issue (which is the only thing that comes to mind for me.)

So you need much stronger praise, please. Go is beautiful (despite its visually ugly syntax) and its use for web apps shows/proves its total appropriateness to all applications.

I want to understand the impediments. It should be much farther along to replacing C and C++.

Also:

>But I worry that Go is moving away from this mantra over the initial specification

I don't have such a worry. I guess you could say:

"But my impression is that the Go compiler leaves a lot of the huge benefit that is still in its specification: that is, a safer replacement for C and C++. It is perfectly viable as a replacement for nearly all C and C++ language work."

I'd like to understand why it isn't doing so yet and what it will take to get there. Hope this helps clarify my thinking.

Turn up the praise.

Not going to edit the above but people clearly hate it (many downvotes without minutes of posting).

At the moment I think most Go programmers who also program tiny microcontrollers with a few hundred KB or up to a couple of MB of RAM, do so in languages like C or Rust, not in Go. Why not? It's a fair question.

For those of you reading this on a laptop or desktop, how many desktop applications are you all running at the moment or have as an installed application? How many are written in Go? Why so few or none?

I mean desktop applications like Audacity for audio, or VLC, or Open Office, or your web browser, and so forth.

The downvotes came pretty fast so you clearly have some ideas. I'd like to hear them.

>people clearly hate it

Maybe because it's overlong, almost completely unrelated to the article, and might just be flamebait?

But I'll toss in a few cents anyway.

>Why can't I compile a Go program targeting a microcontroller with 2-8 MB of RAM without issue?

Microcontroller toolchains are pretty controller-specific. It takes work to make things compile for them. There are other languages that fare better. Additionally, one of the more useful features of Go (concurrent goroutines) would simply be unavailable (and even with concurrency disabled, you still get unpredictable latencies from deciding which task should run when, the GC, etc).

Just use C.

>why can't I develop desktop GUI's in Go

You can. https://github.com/andlabs/ui is an example of how you can (and I'm sure it's not the only one.)

>Why don't people make GUI stuff in Go?

It's common to write apps using whatever the OS provides or using well-known libraries, so that's something Go's offerings don't offer. It's so much work already to build a GUI app that most people doing so probably don't want to concurrently write a GUI library too. I don't think there's anything stopping you, though.

Next time, avoid writing so much to ask two (three?) simple questions. You come off as having an attitude when you use phrases like "Not going to edit the above", "knights in shining armor", and so on. You also build up and tear down many bales worth of strawmen, which is pointless. It would have been a better use of your time to actually look into either of those fields and discover the answers for yourself.

Thanks for your responses, which I read carefully. I hope we can get a bit more out of this conversation.

"Just use C" is odd to me given that Go was originally developed to be an alternative to C (a "systems language") - this was an explicit design goal, and mentioned in the first main sentence of its specification[1]: "Go is a general-purpose language designed with systems programming in mind."

So when you then glance at the adoption for those uses, you would come to the (wrong) conclusion that it must have failed to meet its original design goal of being better for those general use cases. (Or people would be using it). According to its designers, C and C++ programmers don't transition to Go (as its designers had thought they would), but Python programmers do.

So I'd like to understand what it lacks that is holding that back. I see it as clearly superior. Looking at the design, it looks like it met its design goal. So I see it as successful in its bid to be design that is a viable replacement for C as a "systems language", and then despite this successful design now nobody uses it as a systems language.

It would be as though someone set out to make a better bicycle wheel, succeeded, and then nobody uses it as a bicycle wheel (despite its being a better bicycle wheel), while meanwhile the design is being used to haul thousands of tons of freight per year (server microservices). I'm asking, "so why don't we use it as bicycle wheels" and am told "just use a wheel". But I want to understand why, because it seems to me it met its design goal of being a better bicycle wheel.

For the second statement, your statement about "common to write apps using whatever the OS provides or using well-known libraries," makes sense and explains why these libraries didn't exist when Go was made. I don't understand why they are still not a big part of the ecosystem nearly a decade later.

The "knights in shining armor" is a serious statement: the biggest benefit of the Go language is its gatekeepers keeping things out of it, and its extremely orthogonal, tiny syntax, which can be kept in mind along with state. The results of code can be reasoned about without a lot of gotchas. I am therefore wondering what, if anything, these gatekeepers are keeping out which prevents the two parts of the ecosystem which I mentioned, from flourishing.

I don't think Go programmers who are also C and C++ programmers who are used to writing for embedded microcontrollers or for Windows in C and C++ respectively, require deep (or any) changes to the language before as a language it would be suitable to those two cases. You haven't mentioned any.

So I still welcome more viewpoints. I don't see why Go can't replace C and C++ applications across all of the use cases I mentioned, with minimal first-party support by the language developers and maintainers. Doesn't Go also have alternative Go compilers based on the specification?

I did a Google search for alternative Go compilers and the top result is from 2014: https://groups.google.com/forum/#!topic/golang-nuts/EwDS15Ew...

As a followup, why is this the case? I mean, the Specification is quite clear, and it's a tiny language, so in the past 9 years I don't see why there aren't at least a few dozen independent implementations. Is it just not enough time, and we should wait a few decades? Is the issue that Google doesn't need Go for its desktop or mobile development stuff, and doens't need it for microcontrollers, and Go is not really an "independent" entity that is quite independent of Google as a company?

Basically I am wondering why Go in 2018 isn't where C and C++ were by 1998, for example. Despite your detailed answers I don't see the missing pieces.

Go as a syntax is better than C or C++ as a syntax. Its syntax and small and stable language features set are Go's primary advantages, which allows it run on the metal using clearly written standard Go libraries to serve web apps. To me, a microcontroller program running with next to no memory just has to not leak memory or crash, unlike Go running microservices, which have to withstand highly targeted and sophisticated attacks.

Basically, given how I see Go (which is the reason for my very lengthy introduction, so that people could correct me if I'm wrong) I don't see why the language is not very far along where C and C++ blossomed as languages for embedded microcontrollers, and for Desktop applications.

In a way you could say I don't really get what's preventing this. I can't think of any showstoppers.

[1] Go language specification: https://golang.org/ref/spec

I tried to find a succinct question to respond to for your first section, and couldn't. My answer is the same as before: no one has bothered to write a Go runtime that can run on microcontrollers. This is because Go does not do anything fundamentally different from C at that level, except things that are less suitable for low-memory and low-CPU environments; and because it takes a lot of work to write a compiler and runtime for these devices. Note that there are very few compilers for each individual microcontroller. They generally only have one or two.

>I see it as clearly superior.

You are not looking hard enough. Go has flaws, as does any language or tool. It is almost a rule of thumb that not understanding the flaws of a tool is a sign of inexperience with it or alternatives to it. I think if you actually tried to learn and use C and C++, you might better understand the difference.

>I don't see why Go can't replace C and C++ applications

My answer is the same as before: it can, except that C/C++ apps already have that territory, and Go doesn't provide a fundamentally different experience except in lacking libraries for most GUI applications. There are still places it shines, though. For example, it is doing a fine job of replacing C/C++ for cloud orchestration tools; static linking is important to those users, and Go provides it easily.

>Basically I am wondering why Go in 2018 isn't where C and C++ were by 1998, for example.

This is a mathematical error. The C programming language was developed in 1972, and C++ piggy-backed off of C's ecosystem very effectively.

>Go as a syntax is better than C or C++ as a syntax

I don't think I can come up with a better example of a "skin-deep" comparison, nor do I think anyone has actually argued for C/C++'s syntax being actually good.

>stable language features

Didn't Go 1.11 break all of the community's tools? Isn't that why the story we're posting on the comments on exists?

>To me, a microcontroller program running with next to no memory just has to not leak memory or crash,

Some microcontroller programs need to have very low latencies, or the physical things they are connected to will break (the GC defeats this). Some microcontroller programs are only allowed a couple of KB of RAM (Go can't handle that). Most microcontroller programs are compiled without a standard library (and Go would have to provide its own impls of basic Go stuff in order to function). Some microcontroller programs never allocate memory, cannot allocate memory, or must allocate all memory up front. And so on. You can solve these things by having more expensive and fault-tolerant gear, or buying more RAM, or paying people to write more Go compilers/runtimes, etc., but these things get expensive fast; that is often incompatible with the design goals of what microcontrollers are used for. You're welcome to write Go and slap it on a Raspberry Pi, though.

>In a way you could say I don't really get what's preventing this.

Try writing a microcontroller program and GUI app, both in C or C++ and in Go. I very strongly doubt you will succeed faster in Go than in C/C++, in either kind of project, because of multiple factors: ecosystem, communities, example code, language features, existing toolchains and compilers... But if you don't believe me, try it out for yourself.

I read this several times hours apart. Lots of information, thanks. I don't have many questions except this:

"Some microcontroller programs are only allowed a couple of KB of RAM (Go can't handle that)."

What in here...

https://golang.org/ref/spec

...can't you possibly implement in only a couple of KB of RAM? (For what required feature or features can we say for sure that a couple of KB of RAM is insufficient to implement as specified?)

As it turns out, the only mention of the feature is in that link's introduction. The garbage collector (https://github.com/golang/go/blob/master/src/runtime/mgc.go) makes many references to 4KB pages and 1MB arenas. This (the code and the user of the technique) would need some serious reconsideration for small devices.

Isn't the specification the actual language, and Google's compiler just one implementation? (That's true for C/C++.)

Is the specification underspecified or something? We're not talking about a syntactically huge language...

I don't downvote you but ... No one hate your post. It's just an huge wall of text unrelated to the current post. It seems not the good place or the good moment to discuss this. You can maybe try to do an "Ask HN" for open question like this.

I think it's a great place to ask this. The most fantastic people to answer the question are going to be reading a post like this, and what we're reading about (adding a Go language server to core) is a huge and language-specialized feature for core. I look forward to reading people's answers to my questions.

I thought the downvotes were because of something I got very wrong. Anyway I hope to learn from responses even if I got something wrong.

Didn't downvote your post above, so that wasn't me.

That aside, there are some resources around for this though I've not (yet) tried any of them:

* http://embd.kidoman.io - Go Embedded Programming Framework. Seems to support Raspberry Pi and BeagleBone Black.

* https://gobot.io - Robotics more than embedded, but there seems like some overlap. :)

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With the "Why no desktop apps in Go?" question, for me it's because I'd only do so using something like Qt (cross platform).

While there have been several attempts to get usable Go bindings happening for Qt, none of them seem both really well done + long term stable.

The best developed Qt bindings so far are https://github.com/therecipe/qt. But that seems to have tapered off and the developer doesn't seem interested in making it into a team project (eg long term viability). That's my impression anyway, I could be wrong. :)