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submitted 4 days ago by Toes@ani.social to c/foss@beehaw.org
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[-] t3rmit3@beehaw.org 12 points 4 days ago

Understandable, but still kind of sad to see support for 32-bit dying. Mostly because it makes me feel old. :P

i686 is a 32-bit architecture introduced in 1995. 32-bit is still supported.

[-] t3rmit3@beehaw.org 10 points 4 days ago* (last edited 4 days ago)

Yes, but the architectures they are dropping are older 32-bit ones. That's why I said support is "dying", not "dead".

The changelog itself notes that this is about 32-bit support:

Debian's support for 32-bit PC (known as the Debian architecture i386) now no longer covers any i586 processor.

[-] megopie@beehaw.org 9 points 4 days ago

At this point systems that need it are probably a couple decades old at least.

But I’m sure there are people out there who are using some ancient system/program because it does what they need and don’t want to buy a new license or pay for a subscription. Guess they’ll just have to stick with the older versions and keep their systems offline to avoid security issues. Or just emulate an older system when they need it.

[-] dgriffith@aussie.zone 6 points 3 days ago* (last edited 3 days ago)

Lots of expensive industrial equipment runs these kinds of processors still. You can still buy motherboards with 8 bit ISA slots even, although you'll pay quite a premium.

But all of that kind of gear typically runs its own distro with an in-house build system. For example, my work uses a flavour of Buildroot for their embedded Linux systems and you can just set whatever processor type you like all the way back to plain old i386 when you build it.

[-] deadcatbounce@reddthat.com 4 points 4 days ago* (last edited 4 days ago)

Whilst other distros move to a Weston (corrections please?) era Intel x86 2013 ish?

Bravo, I think. That's going to be tough.

On a related track, is there any talk of 128 bit chips in general?

[-] The_Decryptor@aussie.zone 3 points 4 days ago

I think CHERI is the only real attempt at a 128 bit system, but it uses the upper 64 bits for metadata, so the address space is still 64 bits.

[-] deadcatbounce@reddthat.com 1 points 4 days ago

Thank-you a lot for that. I wander around the tech blogs like lobsters etc, Reddit and here but never see anything that i remember seeing (if you follow me), but I don't consciously look.

Encryption lengths are getting long so you'd think it was high time.

Your description sounds like the advent of 32 bits where there was a 16 bit address bus stage.

[-] spit_evil_olive_tips@beehaw.org 2 points 4 days ago

Encryption lengths are getting long so you’d think it was high time.

that's unrelated - AES-256 for example can be executed just fine on either a 32- or 64-bit machine. in theory there's nothing stopping you from running it on an 8-bit or 16-bit CPU (although other considerations related to the size of AES's lookup tables make this unlikely). from some random googling, here is an implementation of Chacha20, another 256-bit encryption algorithm, for 8-bit microcontrollers.

when we talk about 32 vs 64-bit CPUs, in general we're only talking about the address space - the size of a pointer determines how much RAM the computer is able to use. 32-bit machines were typically limited to 4GB (though PAE helped kick that can down the road)

CPU registers can also be sized independently of the address space - for example AVX-512 CPUs have a register that is 512 bits wide even though the CPU is still "64-bit".

[-] deadcatbounce@reddthat.com 1 points 4 days ago* (last edited 4 days ago)

that's unrelated - AES-256 for example can be executed just fine on either a 32- or 64-bit machine. in theory there's nothing stopping you from running it on an 8-bit or 16-bit CPU (although other considerations related to the size of AES's lookup tables make this unlikely). from some random googling, here is an implementation of Chacha20, another 256-bit encryption algorithm, for 8-bit microcontrollers.

I started out programming a 6502a in 1980, 680X0 a little later in 87, so I get that bit, but it's easier doing operations on a larger register. I remember writing code for 8 bit multiplication of floating points.

I enjoyed and understood the rest of your prose though. Didn't do much/any programming/low level after say 2005, and regret it now. Trying to re-learn but things have moved on so much.

I take that there isn't much motivation in moving to 128 because it's big enough; it's only 8 cycles (?) to fill a 512 (that can't be right?).

[-] The_Decryptor@aussie.zone 1 points 4 days ago

I take that there isn’t much motivation in moving to 128 because it’s big enough; it’s only 8 cycles (?) to fill a 512 (that can’t be right?).

8 cycles would be an eternity on a modern CPU, they can achieve multiple register sized loads per cycle.

If we do see a CPU with 128 bit addresses anytime soon, it'll be something like CHERI, where the extra bits are used for flags.

[-] lisko@sopuli.xyz 5 points 4 days ago

Other distros did this a long time ago

[-] smeg@feddit.uk 7 points 4 days ago

Well yeah, isn't long term support and stability Debian's whole thing?

this post was submitted on 17 Feb 2025
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