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jank is C++

(jank-lang.org)
257 points Jeaye | 19 comments | | HN request time: 1.044s | source | bottom
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johnnyjeans ◴[] No.44535498[source]
I'm not surprised to see that Jank's solution to this is to embed LLVM into their runtime. I really wish there was a better way to do this.

There are a lot of things I don't like about C++, and close to the top of the list is the lack of standardization for name-mangling, or even a way mangle or de-mangle names at compile-time. Sepples is a royal pain in the ass to target for a dynamic FFI because of that. It would be really nice to have some way to get symbol names and calling semantics as constexpr const char* and not have to deal with generating (or writing) a ton of boilerplate and extern "C" blocks.

It's absolutely possible, but it's not low-hanging fruit so the standards committee will never put it in. Just like they'll never add a standardized equivalent for alloca/VLAs. We're not allowed to have basic, useful things. Only more ways to abuse type deduction. Will C++26 finally give us constexpr dynamic allocations? Will compilers ever actually implement one of the three (3) compile-time reflection standards? Stay tuned to find out!

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1. benreesman ◴[] No.44535588[source]
Carmack did very much almost exactly the same with the Trinity / Quake3 Engine: IIRC it was LCC, maybe tcc, one of the C compilers you can actually understand totally as an individual.

He compiled C with some builtins for syscalls, and then translated that to his own stack machine. But, he also had a target for native DLLs, so same safe syscall interface, but they can segv so you have to trust them.

Crazy to think that in one computer program (that still reads better than high-concept FAANG C++ from elite lehends, truly unique) this wasn't even the most dramatic innovation. It was the third* most dramatic revolution in one program.

If you're into this stuff, call in sick and read the plan files all day. Gives me googebumps.

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2. johnnyjeans ◴[] No.44535907[source]
Any particular year?
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3. no_wizard ◴[] No.44536648[source]
Carmack actually deserves the moniker of 10x engineer. Truly his work in his domain has reached far outside it because id the quality of his ideas and methodologies
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4. wging ◴[] No.44536873[source]
Quake III Arena was released in 1999. It was open-sourced in 2005.

https://github.com/id-Software/Quake-III-Arena

https://en.wikipedia.org/wiki/Id_Tech_3

(from the source release you can see benreesman remembered right: it was lcc)

5. MangoToupe ◴[] No.44537532[source]
Linking directly to C++ is truly hell just considering symbol mangling. The syntax <-> semantics relationship is ghastly. I haven't seen a single project tackle the C++ interface in its entirety (outside of clang). It nearly seems impossible.

There's a reason Carmack tackled the C abi and not whatever the C++ equivalent is.

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6. PaulDavisThe1st ◴[] No.44537593[source]
There is no C ABI (windows compilers do things quite differently from linux ones, etc) and there is no certainly no C++ equivalent.
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7. caim ◴[] No.44537663{3}[source]
C ABI is the system V abi for Unix, since C was literally created for it. And that is the abi followed by pretty much any Unix successor: Linux, Apple's OS, FreeBSD.

Windows has its own ABI.

The different abi is pretty much legacy and the fact that x86_64 ABI was built by AMD + Linux etc, while Microsoft worked with Intel for the Itanium abi.

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8. caim ◴[] No.44537798[source]
Just parsing C++ is already a freaking hell.

It's no wonder that every other day a new mini C compiler drops in, while no one even attempts to parse C++.

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9. fuhsnn ◴[] No.44538185{3}[source]
There is one pretty serious C++ parser project: https://github.com/robertoraggi/cplusplus
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10. caim ◴[] No.44538300{4}[source]
Wow, thanks! I didn't know this project.

To parse C++ you need to perform typecheck and name resolution at the same time. And C++ is pretty complex so it's not a easy task.

11. bitwize ◴[] No.44538357[source]
I have a bit I do where I do Carmack's voice in a fictional interview that goes something like this:

Lex Fridman: So of all the code you've written, is there any that you particularly like?

Carmack: I think the vertex groodlizer from Quake is probably the code I'm most proud of. See, it turns out that the Pentium takes a few cycles too long to render each frame and fails to hit its timing window unless the vertices are packed in canonically groodlized format. So I took a weekend, 16-hour days, and just read the relevant papers and implemented it in code over that weekend, and it basically saved the whole game.

The point being that not only is he a genius, but he also has an insane grindset that allows him to talk about doing something incredibly arcane and complex over a weekend -- devoting all his time to it -- the way you and I talk about breakfast.

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12. ajkjk ◴[] No.44538490{3}[source]
I like this word, 'grindset'
13. upghost ◴[] No.44538744{3}[source]
Another weird thing about Carmack, now that you mention it -- and Romero, coincidentally -- is their remarkable ability to remember technical challenges they've solved over time.

For whatever reason the second I've solved a problem or fixed a bug, it basically autopurges from my memory when I start on the next thing.

I couldn't tell you the bugs I fixed this morning, let along the "groodilizer" I optimized 20 years ago.

Oh btw Jank is awesome and Jaeye is great guy, and also a game industry dev!

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14. cryptonector ◴[] No.44539049{3}[source]
The C ABI is basically per-platform (+ variations, like 32- vs 64-bit). But you can get by quite well pretending there is something like a C ABI if you use <stdint.h>.
15. mjevans ◴[] No.44539334{4}[source]
I tend to (more easily) remember things that frustrate me but I overcome. Annoyance is a real factor in it.
16. benreesman ◴[] No.44539423{4}[source]
I find it's actually a good guideline for what to work on. If I'm 1, 3, 6, 12 months into a job or some other project and I can't remember what I was doing X months ago it tends to mean that I'm not improving during that period of time either.

Carmack is always trying to get better, do more, push the envelope further. He was never in it for money or fame, he was in it to be the best near as I can tell. And he's still among the truly terrifying hackers you wouldn't want to be up against, he just never stopped. You get that with a lot of the people I admire and try to emulate as best I can, Thompson comes to mind, Lamport, bunch of people. They just keep getting more badass from meeting their passion to the grave, a lifelong project of unbounded commitment to excellence in their craft.

That's who I look up to.

17. MangoToupe ◴[] No.44539973{3}[source]
I just want to double-down on the "fuck windows" bit. No other operating system has been more hostile to developers than microsoft has been. Fuck those assholes and may they burn in hell. I'll never lift a finger to give a shit about windows or any microsoft effort, just like they never devoted any effort to caring about anyone but shareholders and clients who also hate humanity.

I'll help their users insofar as "help" means "shedding windows at any cost".

18. whstl ◴[] No.44540766{4}[source]
The trick for remembering those things is debriefing with other devs and then documenting. And then keep talking about it.

I don't do mind blowing stuff like Carmack but: just yesterday I came across a bug that helps supporting my thesis that "splitting methods by LOC" can cause subtle programmer mistakes. Wanna write a blog post about it asap.

19. Someone ◴[] No.44541880{4}[source]
> And that is the abi followed by pretty much any Unix successor: Linux, Apple's OS, FreeBSD.

Even limiting that to “on x64”, I don’t see how that’s true. To make a syscall, the ABI on Linux says “make the call”, while MacOS (and all the BSDs, I think) says “call the provided library function”.

Also (https://developer.apple.com/documentation/xcode/writing-64-b...): “Apple platforms typically follow the data representation and procedure call rules in the standard System V psABI for AMD64, using the LP64 programming model. However, when those rules are in conflict with the longstanding behavior of the Apple LLVM compiler (Clang) on Apple platforms, then the ABI typically diverges from the standard Processor Specific Application Binary Interface (psABI) and instead follows longstanding behavior”

Some of the exceptions mentioned there are:

- Asynchronous Swift functions receive the address of their async frame in r14. r14 is no longer a callee-saved register for such calls.

- Integer arguments that are smaller than int are required to be promoted to int by the caller, and the callee may assume that this has been done. (This includes enumerations whose underlying type is smaller than int.) For example, if the caller passes a signed short argument in a register, the low 32 bits of the register at the moment of call must represent a value between -32,768 and 32,767 (inclusive). Similar, if the caller passes an unsigned char argument in a register, the low 32 bits of the register at the moment of call must represent a value between 0 and 255 (inclusive). This rule also applies to return values and arguments passed on the stack.