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Comment Re:This was long overdue (Score 2) 17

They were fined 586 million dollars, which is pretty indicative of how much they stole. How many went to jail, well, apparently none. So the government still turning a blind eye to corporate criminals instead fining the investors. Corporate crime, the crime that pays quite well and when you get caught, well, someone else pays that fine, what a disgusting scam. Why is corporate crime out of control, this is exactly why corporate crime is out of control.

Comment Re:C# vs Swift (Score 1) 36

1. While you're completely correct in theory, if all of the mainstream implementations currently work in the assumed fashion then his point is still reasonably valid.

The mainstream implementations optimise for a particular point in the tradeoff space because they're mainstream (i.e. intended to be used in that space). GCs designed for mobile and embedded systems work differently.

2. ARC is designed to minimise the refcount editing / false sharing

I've worked on the ARC optimisations a little bit. They're very primitive and the design means that you often can't elide the count manipulations. The optimisations are really there to simplify the front end, not to make the code better. When compiling Objective-C, clang is free to emit a retain for the object that's being stored and a release for the object that's being replaced. It doesn't need to try to be efficient, because the optimisers have knowledge of data and control flow that the front end lacks and so it makes sense to emit redundant operations in the front end and delete them in the middle. Swift does this subtly differently by having its own high-level IR that tracks dataflow, so the front end can feed cleaner IR into LLVM.

The design of ARC does nothing to reduce false sharing. Until 64-bit iOS, Apple was storing the refcount in a look-aside table (GNUstep put it in the object header about 20 years before Apple). This meant that you were acquiring a lock on a C++ map structure for each refcount manipulation, which made it incredibly expensive (roughly an order of magnitude more expensive than the GNUstep implementation).

Oh, and making the same optimisations work with C++ shared_ptr would be pretty straightforward, but it's mostly not needed because the refcount manipulations are inlined and simple arithmetic optimisations elide the redundant ones.

Comment Re:Deliberately missing the forest for the trees (Score 1) 313

My only hope is that Trump kicks California out of the union for having the most unbalanced budget of any state

Not sure if it's still true, but the last time I looked California would be running a net surplus if it cut its contribution to the Federal budget in half, so I guess that's one way of solving the problem. Kicking out Texas and a few other states that are significant net contributors would help even more...

Comment Re: Deliberately missing the forest for the trees (Score 1) 313

The bulk of immigrants from Eastern Europe do not even compete with the regular native as they tend to be better educated and work at a higher level

Which actually is the problem, and it's a social one not an economic one. Picture this:

You're a British citizen. You grew up in a poor town and went to a crappy comprehensive school. You had no expectations of getting a good job, because there aren't very many in your area. You see immigrants coming in and living in your poor communities and by and large they're not a problem because they're suffering the same problems as you. After you get over the novelty, they just other poor people like you. Fast forward a few years and they've now manage to get qualifications that are recognised here and now they're suddenly getting better jobs than you'd ever qualify for. Their house now has a better car in front of it than yours. They're wearing more expensive clothes than you. You're seeing that social mobility is a real thing - just not for people like you. How does that make you feel?

Sure, the economy as a whole is doing better, but that's not really a great consolation to the long-term unemployed.

Comment Re:how about modules? (Score 1) 193

You can't really have a clean separation between interface and implementation in C++ without radically redesigning the compiler model. Class and function interfaces are simple, but when you throw in templates then you need to be able to have access to all of the code needed to construct a new instance of the template. The original 4Front C++ compiler did this by a horrible dance of trying to compile the code, catching the linker errors, generating code for the missing symbols, and repeating. Modern C++ compilers just generate a copy of every template that a compilation unit needs and expecting the linker to throw away the duplicates (which is why something like LLVM ends up with over a gigabyte of .o files for a 10MB binary). A lot of newer languages get around this by simply not supporting shared libraries, so you can ship the code (or some IR) along with the interface files and your compiler can generate specialised versions at static link time, or by including a big VM so that everything is distributed as some form of IR and you compile on demand.

Comment Re:Another SLOW Language (Score 1) 193

That's not necessarily true. Smalltalk VMs have been written in a subset of Smalltalk that is statically compiled for a while, and these days the JIT parts are written in the full language. In the case of Java, the sun.misc.Unsafe package include pretty much everything that the JVM needs to be able to do in terms of bypassing its own safety guarantees to be able to self host. In Jikes, the JIT and GC are written in Java. The main reason that JVMs are written in C/C++ is that you don't get much benefit from writing the bit of code that is explicitly allowed to violate a language's invariants in that language (and it makes bootstrapping harder).

Comment Re:C++ is due for deletion ... (Score 1) 193

When a "high" level language require half a dozen or so ways to implement a cast, it's time to go.

Of all of the criticisms of C++, this one makes the least sense. Different casts in C++ have very different semantics and one of the worst things that a programming language can do (and which C++ does in many places) is give you the same syntax for different semantics. Are you taking the same set of bits and interpreting them as a different type (typesafe languages don't need this because they don't permit it)? Are you explicitly removing a const qualifier and thus declaring that you know what you're doing when you do something that might break the invariants of an interface (similarly, not permitted in typesafe languages)? Are you saying create a new instance of the target type initialised from this one?

Remember when a programming language was truly object-oriented?

I still use some that are, but C++ is not one of them. If you try to write Smalltalk-like code in C++, you will write almost as bad code as if you try to write C-like code in C++.

Comment Re:Just what we needed (Score 1) 193

Here's the thing. You might not want to look at this:

template <typename S, typename T>
requires Sequence<S> && Equality_comparable<Value_type<S>, T>
Iterator_of<S> find(S& seq, const T& value);

But today, you'll instead find something like this (from the C++17 spec):

template< class InputIt, class T >
InputIt find( InputIt first, InputIt last, const T& value );

You broke it because either T doesn't implement the operator== overload that compares against T correctly, or InputIt doesn't correctly implement operator++ and operator* with the (documented, but not expressed in the code anywhere) requirements of a sequential access iterator. Now, as soon as you find this you know that the first argument must be a sequence (of type S) with elements of type X, that the second argument must be a type such that X == T is well defined, and that the return value will be an iterator into S, which can be dereferenced to give a reference to an X.

If your error is something syntactic, for example you've deleted the operator==(T&) on S, then your compiler will say 'This find function can't be used with this type because you're missing this method', whereas today it will give you a cryptic error about S::operator==(T&) not being defined somewhere in a deep set of template instantiations.

Concepts give you better compile-time error checking, better compile-time error reporting, and better in-code documentation. They're one of the few C++ language features that are purely benefit.

Comment Re:Epicycles (Score 1) 193

I'm no Java fan, but at least everything is a reference, so you don't have copy-by-accident ooga booga.

That's true, but Java doesn't really have an equivalent of the C++11 move idiom. If you want Java-like semantics from C++, just alias your pointers (ideally wrapping them in something like std::shared_ptr first). The term move is actually a little bit misleading: you're copying the object, but you're transferring ownership of the expensive contents of the object. For example, when you move a string you're creating a new string object, but you're not copying all of the string data, you're just transferring ownership of the underlying buffer. This is even more important for collection types, where you really don't want to do a deep copy and delete.

You can implement the same thing in Java by splitting your objects into cheap wrappers that have a reference to an expensive object and then adding a move() method that transfers ownership of the expensive object to the new wrapper, but it's not integrated into the language. The language integration isn't actually essential in C++ either: people have implemented the same thing using a special Move<> template, which could be used as an argument to an overloaded constructor, which would do the move operation. The nice thing about having it in the standard library and with language support is that tooling understands it. Your compiler / static analyser can warn you if you move an object and then try to anything with the old version.

If copying is so bad (which apparently it is because you'll definitely get reamed during a code review if you do), force a copy action via clone(), ike Java

Saying 'copying is bad' is just as wrong as most other 'X is always wrong' rules. Copying for small types is fine. A std::pair of an integer and a float is a couple of instructions to copy and move semantics would make no sense for it. clone() in Java is also problematic because the standard library doesn't distinguish between a deep and shallow clone.

Comment Re:More features. (Score 1) 193

For embedded systems, you really don't want exceptions. The runtime for RTTI and exceptions is bigger than the flash on most systems (I wrote the one that ships on FreeBSD, the PS4, and a few other places - it's not a huge amount of code in the context of a desktop OS, but it's 100KB of object code for the C++ bits, plus the generic stack unwinder - you don't want to burn 150-200KB of space on an embedded system for this) and stack unwinding performance is very hard to reason about in anything realtime. The reason that the Embedded C++ subset excluded templates was that they make it very hard to reason about code size. A small amount of source code can easily become 10-100KB of object code if you instantiate templates with too many different types. Writing foo<Bar>() is now not a simple case of set up the call stack and jump, it's either that simple if someone else has instantiated the same template function, or it's creating an entirely new copy of foo and all other templates that it refers to using the template parameters. This makes it very difficult to work out what changes were responsible for pushing the size above the available space. Actually, it's even worse, because the specialised function might now be simple enough to inline everywhere and give an overall space saving, but reasoning about exactly where that balance is becomes very hard. It's not that C++ generates bigger code than C, it's that object code size in C++ has far less of a direct correspondence with source code size than C.

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