I was curious how defer is implemented. `defer` in Go is famously function-scoped, not lexically-scoped. This means that the number of actively-deferred statements is unbounded, which implies heap allocation.
The answer is that Solod breaks with Go semantics here: it just makes defer block-scoped (and unavailable in for/if blocks, which I don't quite get).
What's the point if it's incompatible? The README suggests using go's testing toolchain and type checker, but that's unreliable if the compiled code has different behavior than the tested code. That's like testing and typechecking your code in a C++ compiler but then for production you run it through a C compiler.
Would have been a lot more useful if it tried to match the Go behavior and threw a compiler error if it couldn't, e.g. when you defer in a loop.
Is this just for people who prefer Go syntax over C syntax?
I don't really "get" the sweet-spot being targeted here. You don't get channels, goroutines, or gc, so aside from syntax and spatial memory safety you're not really inheriting much from Go. There is also no pathway to integrate with existing Go libraries.
Spatial memory safety is nice but it's the temporal safety that worries me most, in nontrivial C codebases.
The claim that no goroutines makes this pointless isn't quite right. Migrated 50 services off Docker Compose using Nomad and half of them had zero concurrency needs. A safe Go-syntax C target is actually useful for that layer.
I'm reminded of the tools in programs like Ghidra or IDA which can take assembly code and convert it into a C-like language. If you could create one of those tools that also takes in the source file so that it names things somewhat reasonably, could you create an anything to C translator? As long as the original file compiles to assembly, that is
I once used Ghidra to decompile a hand-written ARM assembly floating point library and compile the result to a different architecture, and it was significantly faster than GCC’s built in methods…
But in general this kind of thing is very unreliable for any non-trivial code without a lot of manual work, so a better approach could be to compile to WebAssembly which can be translated into C
It may be easier if you also have the original source file (I've not don't much decompilation myself, only seen other people doing it), as more of a custom solution rather than using an existing system
Biggest reason is usually the toolchain. Debuggers, sanitizers, profilers all just work when your target is C. Go through LLVM and you get similar optimization but now you own the backend. With C, gcc and clang handle that part.
> So supports structs, methods, interfaces, slices, multiple returns, and defer.
> To keep things simple, there are no channels, goroutines, closures, or generics.
Sure, slices and multiple return values are nice, but it's not what makes Go good. When people think about Go they usually think about channels and goroutines. YMMV
While I do kind of get what the appeal and target audience is supposed to be, I absolutely don't get why you'd choose a subset and still have it behave differently than the Go counterpart. For me that destroys the whole purpose of the project.
Translating code to C usually results in some nearly unreadable code. I submit the C++ to C translator, cfront, as evidence. I've looked into using C as a target backend now and then, but always "noped" out of it.
I was pleasantly surprised to discover, however, that C code can be readily translated to D.
I don’t think that’s a valid comparison. It compares two entirely different cases.
In general, if the guts of Foo are similar to those of Bar, translating Foo to Bar is fairly easy.
If Foo has additional guts, as in the C++-to-ℂ translator, translating those parts can lead to hard to read code.
In the C-to-D translator case, it’s not Foo that has additional guts, though, but Bar.
Then, a reasonable 1:1 transaction is easy. Doing it in idiomatic style can still be hard, though. For example D has garbage collection, classes and inheritance. I doubt the readily translation of C to D will replace C equivalents (e.g. a garbage collector written in C that’s part of the code) by those where possible.
The answer is that Solod breaks with Go semantics here: it just makes defer block-scoped (and unavailable in for/if blocks, which I don't quite get).
https://github.com/solod-dev/solod/blob/main/doc/spec.md#def...
Would have been a lot more useful if it tried to match the Go behavior and threw a compiler error if it couldn't, e.g. when you defer in a loop.
Is this just for people who prefer Go syntax over C syntax?
In C you can allocate dynamically on the stack using alloca or a VLA.
Spatial memory safety is nice but it's the temporal safety that worries me most, in nontrivial C codebases.
SWIG[0] is a viable option for incorporating C code as well.
0 - https://swig.org/Doc4.4/Go.html#Go
what's the benefit? for loops?
I wonder if it could be integrated with https://github.com/tidwall/neco, which has Go-like coroutines, channels, and synchronization methods.
But in general this kind of thing is very unreliable for any non-trivial code without a lot of manual work, so a better approach could be to compile to WebAssembly which can be translated into C
[1]: https://codapi.org/
It’s a mix of go and rust syntax that translates to C
Sure when I started Go there were Go routines plastered everywhere. And now I think harder: “do I really need a go routine here?”
> To keep things simple, there are no channels, goroutines, closures, or generics.
Sure, slices and multiple return values are nice, but it's not what makes Go good. When people think about Go they usually think about channels and goroutines. YMMV
While I do kind of get what the appeal and target audience is supposed to be, I absolutely don't get why you'd choose a subset and still have it behave differently than the Go counterpart. For me that destroys the whole purpose of the project.
I was pleasantly surprised to discover, however, that C code can be readily translated to D.
In general, if the guts of Foo are similar to those of Bar, translating Foo to Bar is fairly easy.
If Foo has additional guts, as in the C++-to-ℂ translator, translating those parts can lead to hard to read code.
In the C-to-D translator case, it’s not Foo that has additional guts, though, but Bar.
Then, a reasonable 1:1 transaction is easy. Doing it in idiomatic style can still be hard, though. For example D has garbage collection, classes and inheritance. I doubt the readily translation of C to D will replace C equivalents (e.g. a garbage collector written in C that’s part of the code) by those where possible.