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gpderetta

13,786 karma · joined February 28, 2014

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gpderetta··on When the Debugger Lies
At the very least that would warrant an explicit std::abort() or std::unreachable() at the end (or the C equivalent).
gpderetta··on C++26: Trivial infinite loops are no longer undefined behaviour
one could already add loads off a volatile and portably prevent the loop from being optimized. But there was already a lot of existing embedded code that had this sort of loop, (and more will be written as it is an existing idiom) which the committee wanted to un-break.
gpderetta··on C++26: Trivial infinite loops are no longer undefined behaviour
As the only observable behaviour of this_thread::yield is forward progress, because of the as-if rule, the compiler doesn't actually need to replace the loop, when running on a runtime that guarantees preemption. That's the case when std::threads are backed by kernel threads. On a M:N implementation, then yes, a yield would need to be added, but that would be desirable.

Interestingly, posix realtime FIFO scheduling doesn't preempt even on kernel thread based implementations, so one reading of the standard would require yield on this case. But that can actually be potentially catastrophic as FIFO scheduling is expected to be deterministic. But realtime scheduling is already beyond the standard: I doubt gcc and clang will do the transformation by default.

In practice the equivalence is necessary to make some obscure corner of the memory model work and prevent some undesirable optimizations; I expect that in practice the compilers, if they implement this at all, will provide an opt-in flag, but they will optimize as-if the call was there.

gpderetta··on Subnormal floating-point numbers are expensive on Intel processors
right, but the issue was that if an application was linked with a library that happened to link with a fast-math shared library, it would unknowingly bring along the crt code. Now the only way to get it is to use the fast-math flag when linking the final binary, which at least is an explicit request.
gpderetta··on Subnormal floating-point numbers are expensive on Intel processors
IEEE 754 defines bit exact results for a lot of FP operations, including denormals.
gpderetta··on Subnormal floating-point numbers are expensive on Intel processors
larger SIMD ALUs, which also have been around for longer?
gpderetta··on Subnormal floating-point numbers are expensive on Intel processors
IIRC that has been since split out of the flag and need to be asked for separately at link time.
gpderetta··on Fujitsu launches made-in-Japan next-generation CPU FUJITSU-MONAKA
Fujitsu has a long history of designing their own micro but using a standard ISA for HPC. Used to be SPARC, now it is ARM. IIRC Fujitsu were the main architects behind the SVE ARM extension.
gpderetta··on Implementation of GCC's Nested Functions (vs. C++ Lambdas)
Things get complicated when a lambda that capture by reference is capturing things that are not on a single stack frame (or a stack frame at all). Then you have references to references. You could rely on the optimizer, but the capture has ABI implications.
gpderetta··on Why the AfD Wins
It is undemocratic when the democratically elected people wants to subvert the democratic order. Most (but not all!) democratic countries have constitutions that actually limit the power of elected people exactly for this reason. Especially those countries that ended up democratically electing dictators on the eve of WWII have constitutions that severely limit the power of the executive.
gpderetta··on Is it safe to call print in a Python signal handler?
C++11/C11 memory model and atomics provide a more well funded model to interact with signal handler. I'm not sure if POSIX fully embraced it, but it will work well in practice.
gpderetta··on Luanti removed from Google Play due to baseless AI copyright notice
Didn't the international agreements require ratification from legislative?
gpderetta··on Using GCC's Nested Functions with Wide Pointers and No Trampolines II
>You cannot pass a lambda expression to a function that expects a function pointer (e.g. bool(*)(int) in this example)

To be pedantic, you can: as long as the lambda doesn't close over any local variable, the object will decay to a function pointer.

gpderetta··on I’m leaving OpenAI to build telepathy
realistically, it will be used to beam ads to your brain.
gpderetta··on I’m leaving OpenAI to build telepathy
that replaces your monitor.
gpderetta··on UEFA and its national associations will not participate in FIFA competitions
FIA is getting there as well.
gpderetta··on Concurrency, interactivity, mutability, choose two
Are you implying that a single CPU system can't be concurrent?
gpderetta··on Concurrency, interactivity, mutability, choose two
A reminder that databases (as an example) provide all three without issues (at the cost of complexity in the implementation of course).
gpderetta··on Italy Blocks Reproductive Health Websites Women on Web and Women Help Women
of course doctors should not be forced, that's ridiculous, but the SSN should prioritise hiring non-objecting doctors, at least in areas where there isn't enough coverage (in the same way it should prioritise hiring other specialities as needed).
gpderetta··on Italy Blocks Reproductive Health Websites Women on Web and Women Help Women
Agree about that. The question is whether all websites providing black-market potentially generous medications are being targeted or specifically just abortion pills. I genuinely do not know, this might be making the news but actually be part of a wide blockage.
gpderetta··on Italy Blocks Reproductive Health Websites Women on Web and Women Help Women
how's that different from any other medical procedure?
gpderetta··on Italy Blocks Reproductive Health Websites Women on Web and Women Help Women
It is indeed legal, but gynaecologists can object to help for conscientious reasons (65% do) and in quite a few hospitals, 100% do object, especially in the south. So in practice access to it is not always that easy.
gpderetta··on If digital computers are conscious, they are conscious at the hardware level
Agree. Unscientifically, I don't think current LLM are conscious because I don't think they have enough awareness of their own thoughts (I, again unscientifically don't believe that the context window is enough).

Still, tthey are the stuff of sci-fi: it is the first time in recorded history that we can communicate with language with something that is not human! The consciousness "problem" is just a distraction.

Do androids dream of electric sheep indeed.

gpderetta··on $100 AI Music Video: Claude Fable 5 vs. GPT-5.6 Sol
"90% of everything is crap".

Although I guess we should probably update it to "99% of everything is slop.

gpderetta··on Count Binface
damage control in full swing already?
gpderetta··on Count Binface
that's all right, Lord Buckethead has now officially endorsed Count Binface for the by-election: https://xcancel.com/DavidHughesTwit/status/20759264658461409...
gpderetta··on Count Binface
I guess technically he never said it wasn't for security. Apparently the 5m was an unconditional gift for campaigning for brexit, and how he had spent the money was “not the public’s business”.

https://www.bbc.co.uk/news/articles/c072prlxlddo

https://www.channel4.com/news/factcheck/factcheck-the-latest...

gpderetta··on The Graph That Should Be Front-Page News
According to https://climatecasino.substack.com/p/some-monsters-are-real, this is a 1 in 7000 years event (i.e. 3.5 sigmas).
gpderetta··on Count Binface
Are we really still going with the "personal security" story? I thought he had pivoted a couple of times to other, not necessarily more credible, stories.
gpderetta··on Count Binface
> This is the country that voted to name a research vessel Boaty McBoatFace

And "Killing in the Name" as Christmas song of '09, to spite the usual X-factor shoo-in.

There is a chance that more entertainment is yet to come from Clacton.

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