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0 pointsjstimpfle11h ago0 comments

Caring for the actual assembler output in selected critical pieces of code is not the same as ignoring the abstract machine model. What you claim is simply not the case if you check actual proficient systems programmers. Of which there are an astonishingly high share C and C++-but-mostly-C programmers.

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pjmlp11h ago

Any user of compiled languages cares about Assembly, which is why regardless of the compiled language, an Assembler was always shipped alongside.

Also it isn't a C invention to have the compiler dump the Assembly output instead of object code.

Now the culture that C language constructs in 2026 are still 1:1 to Assembly instructions, that pretty much prevails, despite easy proof that isn't the case at various compiler optimization levels.

Proficient devs, well many still don't know to distinguish what is their compiler, and what ISO says.

jstimpfleOP11h ago

It is the case that you can more easily know what happens when you don't use the wrong abstractions but stay in control. Highly-abstracted C++ code basically makes allocations and syscalls in the whitespace between the source code tokens. You can't do systems software like that, you have to roll back the abstractions and roll back the use of pre-canned containers and libraries that you don't understand.

So it's all about understanding and control, not about some idea that C was defined in terms of assembly instructions, which it obviously is not. That's a total strawman.

pjmlp10h ago

Except modern C also has plenty of abstractions, devs wrongly assume it doesn't.

Then get surprised when it doesn't map to the SIMD/SIMT NUMA machine their code actually executes on.

uecker10h ago

There is not much real evidence for "devs wrongly assume" and as someone writing numerical code (clusters, NUMA, SIMD, etc.) I think C is still the ideal tool for this.

jstimpfleOP10h ago

such a strawman again... You don't want to be writing explicit platform specific SIMD most of the time. You just want to write a dumb function that doesn't do any non-obvious calls, doesn't cause thread contention, doesn't hide complexity, isn't going to be a nightmare to change later, no surprises.

I am talking about self-inflicted complexity that is entirely within the C(++) machine model. Avoid that and you're pretty good already. Only drop down to concrete hardware arch level where it makes sense. But largely, the C machine model is still very much suited as a model for actual hardware. Writing straightforward obvious code allows you to stay in control of memory layout and the data transformation paths. It easily gets you within <<2x of what you could achieve with hand coded assembler for the >90% of the code that are pretty boring and straightforward. And obviously you couldn't get the work done in time when coding everything in assembler.

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