• BartyDeCanter@lemmy.sdf.org
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      7 months ago

      There is no C++ allowed in the Linux kernel and Linus has gone on several major rants about how terrible a language it is.

    • Rossphorus@lemm.ee
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      7 months ago

      Torvalds just really dislikes C++. He’s gone on the record saying that he thinks it’s just not a good language. In his own words “C++ is just a waste, there is no design at all, just adding some scum on top of C.”

          • Vilian@lemmy.ca
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            7 months ago

            they dumped everything in the languaga, at least samething they needed to have right, it’s otherwise statistically impossible

          • magic_lobster_party@kbin.run
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            7 months ago

            The STD is maybe the only good thing C++ has over C, and even that is awful compared to other language’s standard libraries.

            I can’t name another good thing C++ has. Maybe templates. C++’s reliance on inheritance for polymorphism is awful (should’ve gone with interfaces/traits).

            Not to mention the mess with all the different types of constructors that must always be implemented.

            It’s just a bunch of bad design choices added on top of an old outdated language.

            • acockworkorange@mander.xyz
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              7 months ago

              The STD is maybe the only good thing C++ has over C, […]. I can’t name another good thing C++ has. Maybe templates.

              Are you high? I was praising the STL, you know, the template library?

      • blind3rdeye@lemm.ee
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        7 months ago

        I would have agreed with that before C++11. But since then, C++ has improved a lot. Its like the vision of what C++ suddenly became more clear. So I wonder if Linus would still say that today. (Unfortunately, there have been a lot of missteps in the development of C++ though, and so there is a lot of cruft that everyone wishes was not there…)

    • jalkasieni@sopuli.xyz
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      7 months ago

      ”C++ is a horrible language. It’s made more horrible by the fact that a lot of substandard programmers use it, to the point where it’s much much easier to generate total and utter crap with it. Quite frankly, even if the choice of C were to do nothing but keep the C++ programmers out, that in itself would be a huge reason to use C.”

      http://harmful.cat-v.org/software/c++/linus

    • raoul@lemmy.sdf.org
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      7 months ago

      I don’t know about Linus, but the last time Reiser’s wife was seen, she was writing a c++ hello world

          • BartyDeCanter@lemmy.sdf.org
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            7 months ago

            Take a look at what even the proposer is saying wouldn’t be allowed in:

             (1) new and delete.  There's no way to pass GFP_* flags in.
            
             (2) Constructors and destructors.  Nests of implicit code makes the code less
                 obvious, and the replacement of static initialisation with constructor
                 calls would make the code size larger.
            
             (3) Exceptions and RTTI.  RTTI would bulk the kernel up too much and
                 exception handling is limited without it, and since destructors are not
                 allowed, you still have to manually clean up after an error.
            
             (4) Operator overloading (except in special cases).
            
             (5) Function overloading (except in special inline cases).
            
             (6) STL (though some type trait bits are needed to replace __builtins that
                 don't exist in g++).
            
             (7) 'class', 'private', 'namespace'.
            
             (8) 'virtual'.  Don't want virtual base classes, though virtual function
                 tables might make operations tables more efficient.
            

            C++ without class, constructors, destructors, most overloading and the STL? Wow.

            • ozymandias117@lemmy.world
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              7 months ago

              That doesn’t really surprise me, as most of those are the same requirements from any embedded development use case using c++ that I’ve worked on

              4 and 5 are the only ones stricter than I’m used to

              • BartyDeCanter@lemmy.sdf.org
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                7 months ago

                I’ve only worked on a few embedded systems where C++ was even an option, but they allowed 2, 4, 5, and 7. Though, for the most part most classes were simple interfaces to some sort of SPI/I2C/CAN/EtherCAT device, most of which were singletons.

      • nandeEbisu@lemmy.world
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        7 months ago

        I don’t think its the ergonomics of the language he has an issue with. If anything C++1x probably just made the original critiques of bloat worse.

        • ozymandias117@lemmy.world
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          7 months ago

          In that post, his critiques were around the problems with the STL and everyone using Boost. The STL has improved significantly since then, and it would be a limited subset of c++ if it was ever allowed

          There have been mailing list conversations earlier this year, citing that clang/gcc now allowing c++ in their own code might mean they’ve taken care of the issues that made it unusable for kernel code

          https://lore.kernel.org/lkml/[email protected]/

          I’m not saying it will happen, but it’s not being shot down as an absolute insanity anymore, and I wouldn’t have expected Rust to be allowed in the kernel, either

          • nandeEbisu@lemmy.world
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            7 months ago

            Oh interesting. I didn’t realize boost was the main issue. Most people I’ve talked to were complaining about VTables introducing a bunch of indirection and people blindly using associative containers.

            • ozymandias117@lemmy.world
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              7 months ago

              Vtable equivalents are used extensively in the kernel

              You’ll find structs all over the place setting them up, e.g. every driver sets up a .probe function that the core will call, since it doesn’t know what driver it’s loading

              • nandeEbisu@lemmy.world
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                7 months ago

                Right the issue was more because they’re so easy to throw in without thinking about it so people overuse them. That may just be older devs complaining about newbies though.

    • voxel@sopuli.xyz
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      7 months ago

      ”C++ is a horrible language. It’s made more horrible by the fact that a lot of substandard programmers use it, to the point where it’s much much easier to generate total and utter crap with it. Quite frankly, even if the choice of C were to do nothing but keep the C++ programmers out, that in itself would be a huge reason to use C.”

      http://harmful.cat-v.org/software/c++/linus

  • Bye@lemmy.world
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    7 months ago

    The day I learned that Linus shares my disdain for all things OOP was such a good day for me.

    • ADTJ@feddit.uk
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      7 months ago

      Me, when Linus’ opinion is different to mine: “Linus has such weirdly strong opinions about this

      Me when Linus’ opinion is the same as mine: VINDICATION

    • evranch@lemmy.ca
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      7 months ago

      I feel the OOP debate got a bit out of hand. I hate OOP as well, as a paradigm.

      But I love objects. An object is just a struct that can perform operations on itself. It’s super useful. So many problems lend themselves to the use of objects.

      I’ve been writing a mix of C and C++ for so long I don’t even know where the line is supposed to be. It’s “C with objects”. I probably use only 1% of the functionality of C++, but that 1% is a huge upgrade from bare C IMO.

      • namingthingsiseasy@programming.dev
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        7 months ago

        Agreed. Objects are nice and a great way to program. Composition is great. Traits/interfaces are great. Namespaces are great. Objects are a really nice way to reap the benefits of principles like these.

        But then there are aspects of OOP that absolutely suck, like inheritance. I hate inheritance. The rules get very confusing very quickly. For example, try understanding overriding of methods. Do I need to call the superclass method or not? If not, does it get called automatically? If so, in what order? How do these rules change for the constructor? Now repeat this exercise for every OOP language you use and try not to mix them up… Java, C++, Python, etc.

        Fortunately, it feels like we rely on inheritance less and less these days. As an example, I really like how Java allows you to implement Runnable these days. Before, if you wanted to run a thread, you needed a separate object that inherited Thread. And what if that object needs to inherit from another one too? Things would get out of hand quickly. (This is a very old example, but with lambdas and other new features, things are getting even better now.)

        Anyway, long story short, I think OOP is a complicated way to achieve good principles, and there are simpler ways to achieve those principles than a full OOP implementation.

        • CapeWearingAeroplane@sopuli.xyz
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          7 months ago

          I’ve seen this thing where people dislike inheritance a lot, and I have to admit that I kind of struggle with seeing the issue when it’s used appropriately. I write a bunch of models that all share a large amount of core functionality, so of course I write an abstract base class in which a couple methods are overridden by derived models. I think it’s beautiful in the way that I can say “This model will do X, Y, Z, as long as there exists an implementation of methods A, B, C, which have these signatures”, then I can inherit that base class and implement A, B, and C for a bunch of different cases. In short, I think it’s a very useful way to express the purpose of the code, without focusing on the implementation of specific details, and a very natural way of expressing that two classes are closely related models, with the same functionality, as expressed by the base class.

          I honestly have a hard time seeing how not using inheritance would make such a code base cleaner, but please tell me, I would love to learn.

      • AeonFelis@lemmy.world
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        7 months ago

        I think the problem with OOP is something you can see whenever legislation is linked with prestige (it happens a lot in real life). The number of good possible rules is quite limited, and the number of people who want to make a name for themselves by championing them seems to be infinite. If you can’t find a good rule to claim as your own, you have to pick a bad rule and try to gaslight people into thinking it’s a necessary and beneficial. Enough people do that, and we end up with modern OOP.

    • jabjoe@feddit.uk
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      7 months ago

      He is is OK with OOP. The Linux kernel is full of OPP C, but he doesn’t like C++

        • jabjoe@feddit.uk
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          7 months ago

          Look at the kernel code. It’s full of OOP C. There absolutely are objects in the kernel.

          • refalo@programming.dev
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            7 months ago

            Yea but all that function pointer indirection can actually hurt performance (especially caching), some things in C++ actually can be faster just because the compiler is better at optimizing for that.

            • jabjoe@feddit.uk
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              7 months ago

              There is nothing you can do in C++ or C, that can’t be done in the other. It’s the kind of the point of those languages.

              • refalo@programming.dev
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                7 months ago

                Technically you’re right, but I don’t think that changes what I said about optimization. There are still cases where equivalent C++ code can be faster than the C version merely due to different optimizations used.

                • jabjoe@feddit.uk
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                  7 months ago

                  Meh, I’m unconvinced. If it’s any kind of hot spot, in either, you can optimize the hell out of it. C++ is often more bloated is it’s just a harder language pretending to be an easier one.

    • expr@programming.dev
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      7 months ago

      Yeah it’s pretty great, especially when so many people are so quick to assume that OOP is essential for managing complexity.

      OOP is the poster child for solving the problems that it creates itself.

    • themoken@startrek.website
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      7 months ago

      For kernel dev it would be a disaster, there’s too much implicit action, and abstractions that have unknown runtime cost. The classic answer is that everyone uses 10% of its features over C, but nobody can agree on which 10%.

      As someone forced to get up to date with C++ recently, at this point it’s a language in full identity crisis. It wants so badly to be Rust, but it’s got decades of baggage it’s dragging along.