> An object of dynamic type Tobj is type-accessible through a glvalue of type Tref if Tref is similar ([conv.qual]) to: Tobj, a type that is the signed or unsigned type corresponding to Tobj, or a char, unsigned char, or std :: byte type. If a program attempts to access ([defns.access]) the stored value of an object through a glvalue through which it is not type-accessible, the behavior is undefined.
The dynamic type of a char buffer is, well, a char buffer, and can only be accessed via things that are the same type as a char buffer up to signedness and cv-qualification. The actual strict aliasing rules are not commutative!
I've already been using it for some time (debian sid has a trunk package). it has c++26 reflection, so I already do some magical things with reflection (much better for some cases e.g. for ser-des).
I only wish they had a lsp server in their eco-system!
Large projects have been going to regular scheduled releases for a long time. Until the 90's people thought they could waterfall a large release with all your desired features (and for tiny projects this is still a good idea), but as your projects grow (possibly just to small) you reach a point where someone is always working on a feature that isn't ready yet, so a regular release means you still can support your customers with releases. This forces developers who are unsure they will be ready to have some sort of "disabled this unstable feature" toggle, which is about the best you can do.
Yup. OpenJDK is one of the best success stories of this.
Up until Java 9, they would release once features were complete. But that meant there were years between the 7 and 8 release and even more years between the 8 and 9 release.
The industry had gotten into the habit of always running old versions of Java (my company was on 6 for an uncomfortable amount of time. But others have had it worse).
More frequent smaller releases has gotten companies more into the habit of updating frequently which also, very helpfully, gives devs new features frequently.
The Linux kernel is another example. The 2.5 development cycle (which led to the stable 2.6 series) was brutally long, and distros resorted to back-porting new features into their own kernels based on the stable 2.4 series that they provided to their users, creating all kinds of excitement. After 2.6.0 was released, Linux basically went nope, not gonna do that again.
Are there any large projects that are older than 25 years that didn't go through that? The time based release thing as been recommended for about 25 years (can anyone get real data?), so newer projects may just be using it without knowing the pain, but for older projects it seems like they all went through it at least once.
Yeah, GCC’s recent major releases have been remarkably regular, much like Fedora’s spring releases, and their releases seem to fit into the same broader rhythm. Hint? Red Hat.
For many years that was the only version that could be used. What become gcc3 took years. In the end it was better, but for a while gcc 2.95 was the best we had despite the bugs.
I tried the unstable sources for a while, in the last ~3 months. I ran into some issues with some programs (could not compile them with recent GCC, but older GCC worked fine), so gcc 15.x works better for me in general (presently) - but from, say, +3000 programs to compile, the vast majority works well, and a few may need patches (which can often be found in LFS/BLFS by the way, they often use sed instructions to fix individual things and then it works usually).
Hopefully they fixed those issues. We all need stability and things-to-work.
Nearly all zero-copy code that deals with external I/O buffers looks something like:
With this merged, swap the reinterpret_cast for start_lifetime_as and you're no longer being naughty.https://en.cppreference.com/cpp/memory/start_lifetime_as
You're allowed to access any type via a char buffer. But the converse is not true (quoting https://eel.is/c++draft/expr#basic.lval-11):
> An object of dynamic type Tobj is type-accessible through a glvalue of type Tref if Tref is similar ([conv.qual]) to: Tobj, a type that is the signed or unsigned type corresponding to Tobj, or a char, unsigned char, or std :: byte type. If a program attempts to access ([defns.access]) the stored value of an object through a glvalue through which it is not type-accessible, the behavior is undefined.
The dynamic type of a char buffer is, well, a char buffer, and can only be accessed via things that are the same type as a char buffer up to signedness and cv-qualification. The actual strict aliasing rules are not commutative!
Malloc returns a buffer and then you cast it to the type you want. Similarly for all memory allocators.
Punning the same region of char buffer as two different types is a bit different.
Up until Java 9, they would release once features were complete. But that meant there were years between the 7 and 8 release and even more years between the 8 and 9 release.
The industry had gotten into the habit of always running old versions of Java (my company was on 6 for an uncomfortable amount of time. But others have had it worse).
More frequent smaller releases has gotten companies more into the habit of updating frequently which also, very helpfully, gives devs new features frequently.
It used to be slower and I've spent way too much time working around C++ bugs in GCC 2.95
(The fact that I remember the problematic version is telling :)
Hopefully they fixed those issues. We all need stability and things-to-work.