Name something more iconic than the TP7-era color scheme of Turbo Vision: https://free.oberon.org/docs/en/Strings.html
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Per Vognsen
@pervognsen@mastodon.social
mastodon 4.8.0-nightly.2026-10-06I like programming and understanding how stuff works. My background is in systems programming and game development.
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Joined September 11, 2018
What is going on in C++ land... "When possible, avoid the u8 prefix. It has significantly different semantics starting in C++20 than in C++17, producing arrays of char8_t rather than char, and will change again in C++23."
Almost every time I see saturating add/multiply used to avoid overflows, it's silently wrong or if it's only accidentally right (just because a big wrong number from saturation is a safer bound than a small wrong number from wrapping).
The scourge of x86 emulation: https://fex-emu.com/Scourge-of-emulation/. An article on TSO emulation by the FEX devs. When I saw the (excellent!) presentation at CCC on FEX this year my biggest question was about how they were dealing with TSO.
What is going on in C++ land... "When possible, avoid the u8 prefix. It has significantly different semantics starting in C++20 than in C++17, producing arrays of char8_t rather than char, and will change again in C++23."
Boosted by @joe@f.duriansoftware.com
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@joe@f.duriansoftware.com Remember when this was all the rage in UI design?
How to recalculate a spreadsheet, https://lord.io/spreadsheets/. Not just about spreadsheets, but any structurally similar system. A great, accessible overview if you don't feel like diving through the literature.
I guess this deserves to be posted on a regular cadence for the benefit of anyone who hasn't seen it before: https://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres_are_switching_written_numbers_when_scanning
Once again reminding you of The Trick to reduce the critical decoding path of any off-the-shelf variable-length data format. Split each variable-length item into a small fixed-length part that uniquely determines the length of the remaining variable-length part. Then split the fixed-length and variable-length parts into two streams and use prefix sums: https://gist.github.com/pervognsen/547113f6b368317d86110a6bb01ce314
An interesting example of parallel discovery: the zero memory widget (ZMW) library released in 2003 (discovered in 2001-2002) vs Casey's first presentation of immediate-mode UI in 2005 (discovered in 2002). I assume approximately no-one has heard of ZMW. https://perso.univ-lyon1.fr/thierry.excoffier/ZMW/zmw-0.2.4/zmw.html
With the DRAM shortage, maybe it's time for RAM Doubler and other assorted scamware to make a comeback. On that note, https://devblogs.microsoft.com/oldnewthing/20211111-00/?p=105897
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The ultimate reductio ad absurdum would be if we start putting machine code bytes in inline asm blocks only for compilers to eventually start "helpfully" disassembling them to perform intrinsic substitutions.
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@regehr@mastodon.social @zwarich@hachyderm.io @joe@f.duriansoftware.com Heh, speaking of 0.0f/0.0f crashing the tested compiler (one of the table 1 examples), you can still crash tcc today (last I checked) with INT_MIN/-1 on x86. I like to test any program that has a built-in expression evaluator with that and it's scary (but many not surprising) how many you can crash with it.
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@steve@discuss.systems @joe@f.duriansoftware.com I'm more interested in the SIGBOVIK version of this, inspired by those terrible underdetermined sequence extrapolation puzzles. On a side note, when I first was exposed to Haskell in the late 90s and saw the syntax [a, b..c] I was excited for a second that it might be more general (i.e. not be limited to arithmetic progressions).
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@zeux@mastodon.gamedev.place It's funny to think back to how much confusion there was about tangent space generation in the early days of the normal mapping era. It's not something I've thought about in approximately 20 years, so I'm looking forward to what you're cooking.
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@adrian@discuss.systems This reminds me, I currently have separate Firefox add-ons for old.reddit.com and nitter.net redirects. There should really just be a generic regex-based redirect add-on. I just checked, and indeed there is: https://addons.mozilla.org/en-US/firefox/addon/redirector/?utm_source=addons.mozilla.org&utm_medium=referral&utm_content=search
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Example: In C, ? : is annoying in a single-pass compiler because you have to go back and insert an int-to-double conversion at the end of the basic block, or more likely you use a shim basic block just for that conversion (which I believe is what tcc does), once you determine that the overall expression has type double. You have the same problems (and same solutions) when single-pass compiling the equivalent case with let assignments.
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I guess in the case of airlines they don't even need to appeal to force majeure because they already cancel underbooked and otherwise unprofitable flights all the time, so this is an application of existing practices on a larger scale.
The NBA Jam repo on historicalsource has a bunch of doc files that are a time capsule from 1992. Here's a fun excerpt, relative to what actually happened: "The NBA has been cautious about entering the European market, it's understandable. The NBA, it is believed, will grant franchises and expand into Europe within the next few years." https://github.com/search?q=repo%3Ahistoricalsource%2Fnbajam-complete%20doc&type=code
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@joe I'm going to bet this is closer to "random junk in the attic" than "divorce asset".
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Also, I didn't know that VisiCalc literally did brute-force fixed-point iteration without any sorting, so that was a neat bit of history on its own.
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@soller@floss.social Yup. Even my most optimistic prediction involves it getting a lot worse before it starts getting better again.
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@sschoener@mastodon.gamedev.place @vurtun@mastodon.gamedev.place There's ZLUDA as well in the "CUDA on AMD" category and it's much further along: https://vosen.github.io/ZLUDA/blog/zluda-update-q4-2025/ If you write stuff like "LLVM is NOT required. BarraCUDA does its own instruction encoding like an adult" (which the README is full of) any criticism of your effort seems fair game. It would definitely be nice to have something standalone, though.
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@wolfpld@mastodon.gamedev.place The paradox of tolerance but for coding agents: if you use coding agents, should you use coding agents written by coding agents?
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The simplest version of the single-pass algorithm (with no support for subtyping) is that the first (in source order) assignment to a let variable fixes the variable's type and any other assignments to the same variable (necessarily on disjoint paths) check against that type.
Anyway, I used to think that one objective advantage of expression-oriented initialization was its simpler interaction with type propagation, but this shows that isn't actually a real difference.
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@siguza BTW, I should have clarified (as mentioned later in the linked thread) that this feature was actually removed in response: https://github.com/llvm/llvm-project/issues/156571 So all is well, for now.
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@lenary Yeah, found the comments on that in the proposed LangRef changes. It's good that this is at least getting nailed down.
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@harold I always think of it like flying around the Earth to chase the Sun--ultimately you have to "pay off" your time debt in a feedback circuit, but you can shift around where it is in the multi-cycle feedback loop depending on timing closure requirements.
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@vurtun@mastodon.gamedev.place @sschoener@mastodon.gamedev.place Also, it's not "just" documentation and tests he's writing with coding agents. Just look at his GH output. It's hundreds of thousands of lines per month for dozens of new projects. Here's just one initial commit for one of his random projects that has 300,000 added lines.
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@chandlerc@hachyderm.io @meowray@hachyderm.io The review culture thing also came up in https://www.npopov.com/2026/01/11/LLVM-The-bad-parts.html
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@zeux Sure, in this case I'm just trying to describe how the two cases (assignment vs expression-oriented initialization) aren't any better or worse for this kind of example, for the small subset of people who care about such things (a non-empty set that includes me).
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@zeux My immediate use-case is actually a lot like that but rather than chunking by a fixed quantity like K it's chunking on basic block boundaries for a variable-length instruction format.
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@shachaf The ability to split on basic block boundaries like that does assume you have some sort of static or dynamic CFI validation so untrusted code can't jump into the middle of basic blocks.
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@MikkoMononen@mastodon.gamedev.place Nice article! Even augmented with some of the additional information (e.g. the override flags), the derived data still feels more like a snapshot representation than a delta/change-based representation. My intuition is that a delta representation would be better at capturing the user's intention and therefore be better for rebasing, but I haven't thought deeply about it.