Comment by kmeisthax | Hacker News Reader

Comment by kmeisthax | Hacker News Reader

Parent Full thread

Indeed. The vast majority of computing environments are covered by existing rustc support. However, people in weird retrocomputing environments are more or less existentially threatened by Rust.

In my personal experience (since I wanted to see how big of a problem this is), I looked into bringing up Rust as a cross-compiler for Mac OS 9. This requires a compiler that can emit PowerPC machine code, as well as a toolchain that can handle XCOFF objects and classic Mac OS's strange resource formats (if you ever wondered why Win32 has resources, that's why). Retro68k provides such a toolchain (albeit GCC based), and I wrote a rustc target file to make it spit out XCOFF objects in PowerPC format.

Then I got hit with a bunch of llvm assertions about unimplemented functionality in it's XCOFF generator and gave up.

Less anecdotally, the ArcaOS people (responsible for trying to keep IBM's freakshow fork of Windows and DOS alive) and TenFourFox both have abandoned attempts to maintain Firefox forks for OS/2 and old Mac OS X (respectively), specifically because of the Quantum update making Rust a requirement to build Firefox.

I heard Rust did merge in a GCC backend, which might help some of these retrocomputing projects... but there are platforms out there where the primary (or only) development environment is a proprietary C compiler. (e.g. Classzilla uses Metroworks to provide old Mozilla on Mac OS 9) I'm starting to wonder if some kind of "Rust to C" backend might be useful for these cases...

Linux also can't abandon hardware support for some of these weird environments, either. So until and unless Rust-with-GCC can compile on every environment Linux does, we aren't going to see anything more than Rust drivers.

> Linux also can't abandon hardware support for some of these weird environments, either.

Can't because why though? I agree it shouldn't abandon them just to get more Rust, but there are other reasons some of the crustier less used platforms go away.

> Linux also can't abandon hardware support for some of these weird environments, either.

But why not? Are we obligated to support everything forever? If it’s hardly being used, and is starting to get in the way of safety and correctness improvements, why can’t we drop something old, arcane and unused?

Counterpoint: not all of this is actually going unused. Yes, Debian popcon is going to show the vast majority of users on x86 and ARM; but that is primarily consumer use cases.

When you get into embedded, you will start to see all sorts of weird arcane setups that actual businesses rely upon. Case in point: this commercial kitchen appliance that is actually a DOS PC built with modern parts. [0]

Not to mention the startlingly high number of large businesses running off of IBM server hardware. Much of that is actually legacy stuff that's been rebranded and massively upgraded over the years. A company that bought into System/360 in the 80s or AS/400 in the early 90s will almost certainly have backwards-compatible zSeries or System i hardware running literally 30-40 year old programs.

Point is, there's lots of business critical crap running on things other than x86 or ARM. I only used retrocomputing as an example because I had a good anecdote for it. Businesses treat computers as if retrocomputing was also somehow mission critical and they pay handsomely for the privilege.

[0] https://www.youtube.com/watch?v=BdSJgoP2a88

> will almost certainly have backwards-compatible zSeries or System i hardware running literally 30-40 year old programs.

But like, isn’t that a them problem? If you want to calcify your compute layer, don’t be surprised when the rest of the industry moves on, and possibly does things that aren’t compatible anymore? If they want to keep running that software, I think it’s their responsibility to either evolve their software to keep up, or deal with the fact that they’ll have to run their own old version/fork when the time comes.

If they contribute to the kernel, I would have thought their perspective would have been represented on one of these threads by now, as they seem to get posted at pretty much every event hahaha. Maybe they do and I totally missed it as well.

> old, arcane and unused?

But it is used by retrocomputing enthusiasts. Linux has been supported by them for the platforms they care. They gladly hold up the bar “now you have to support Linux yourself”, with C compilers already existing and being supported by someone else. With Rust becoming a build-time dependency, things suddenly turn into “you're not getting any Linux until you port rustc to your platform and then make sure it's working there at all times”.

So everyone is not getting a more secure/safe system because a small minority wants to run Linux on old computers? That does not sound fair to me. Why can't they not use old versions of Linux as well.

Reply on news.ycombinator.com