> Relying on absence of UB is not the same as relying on existence of UB. I'm not surprised however that you find this difference difficult to grasp.
You are coming with complete inanity, instead of fixing your understanding of a subject that you obviously do not have a good understanding of and that I have a much better understanding of than you, as you are well aware of.
You are making both yourself and your fellow Rust proponents look extremely bad. Please do not burden others with your own lack of competence and knowledge. Especially in a submission that is about a bug caused by Rust software.
You might be mixing up who you are replying to. I never claimed that C and C++ package management are better than what Rust offers overall. In some regards, Cargo is much better than what is offered in C and C++. I wouldn't ascribe that to a mess, more the difficulty of maintaining backwards compatibility and handling cruft. However, I know of people that have had significant trouble handling Rust. For instance, the inclusion of Rust in bcachefs and handling it in Debian that whole debacle.
They did not have an easy time including Rust software as I read it. Maybe just initial woes, but I have also read other descriptions of distribution maintainers having trouble with integrating Rust software. Dynamic binding complaints? I have not looked into it.
Nope, I am not moving the goalposts, as is perfectly clear to you already. You are well aware that I am completely correct and that you are wrong.
> Again, the fact that Rust can and will break backwards compatibility is not in dispute. It's specifically the claim that it's done "on a whim" that was the seed of this subthread.
And you and the other Rust proponent's directly talking around it, as you again are doing here, only worsens the situation.
> No need for a thought experiment. Straight from the GCC docs [0]:
Technically correct, but outside of extensions that has to be enabled, more or less none of that breaks any backwards compatibility. A program written in pure C or C++ ought to behave exactly the same and compile exactly the same as in those default dialects. The default dialects amount to more or less just a strict superset that behaves the same, like adding support for C++ "//" comments, or backporting newer C standard changes to previous versions. The only extensions that change behavior significantly and are not only strict supersets with same behavior, require flags to be enabled.
Thus, yet again, radically different from what the rustc developers did just last year.
Overall, your posts and the posts of your fellow Rust proponents in this submission both worsen the situation for Rust and for software overall regarding compatibility, security and safety, as the bug of the submission indicates. Imagine being so brazen and doubling down on a path that arguably lead to a very public bug. I do not believe any responsible software company would want you anywhere near its code if it cared about safety and security.
> From the fact that a lot of compilers can and do rely on UB to do certain optimizations.
Your understanding of both C, C++ and Rust appear severely flawed. As I already wrote, rustc also uses these kinds of optimizations. And the optimizations do not rely on UB being present in a program, but on UB being absent in a program, and it is the programmer's responsibility to ensure the absence of UB, also in Rust.
Do you truly believe that rustc does not rely on the absence of UB to do optimizations?
Are you a student? Have you graduated anything yet?
> You're however absolutely free to find me one large project that will not trigger "-fsanitizer=undefined" for starters. (Generated codebases do not count though.)
You made the claim, the burden of proof is on you. Though your understanding appear severely flawed, and you need to fix that understanding first.
> Difficult to understand or being unsafe does not make unsafe Rust worse than C. It's an absurd claim.
Even the Rust community at large agrees that unsafe is more difficult than C and C++. So you are completely wrong, and I completely right, yet again.
This new post you have made again reinforces the general notion that, yes, closer to "on a whim" than many like, the Rust community is willing to break backwards compatibility. It reflects extremely poorly on the Rust community in some people's eyes that you and other proponents appear to not only be unwilling to admit the issues, like the above issue that caused some people a lot of pain, but even directly talk around the issues.
In C and C++ land, if gcc (as a thought experiment) tried breaking backwards compatibility by changing the language, people would be flabbergasted, complain that gcc made a dialect, and switch to Clang or MSVC or fork gcc. But for Rust, Rust developers just have to suck it up if rustc breaks backwards compatibility. Like Dtolnay's comment in the Github issue I linked indicates. If and once gccrs gets running, that might change.
Though I am beginning to worry, for the specification for Rust gotten from Ferrocene might be both incomplete and basically fake, and that might cause rustc and gccrs to more easily risk becoming separate dialects of Rust, which would be horrible for Rust, and since there should preferably be more viable options in my opinion of systems languages, arguably horrible for the software ecosystem as well. I hope that there are plans for robust ways of preventing dialects of Rust.
If breakage is not due to a language change, and the program is fully compliant with the standard, and there is no issue in the standard, then the compiler has a bug and must fix that bug.
If breakage is due to a language change, then even if a program is fully compliant with the previous language version, and the programmer did nothing wrong, then the program is still the one that has a bug. In many language communities, language changes are therefore handled with care and changing the language version is generally set up to be a deliberate action, at least if there would be breakage in backwards compatibility.
I do not see how it would be possible for you not to know that I am completely right about this and that you are completely wrong. For there is absolutely no doubt that that is the case.
> In any case though, bringing up language specification as an example for maturity is such a massive cop-out considering the amount of UB in C and C++.
I would use a newer version of C, and consider picking C++, if the choice was between C, C++, Ada, and Rust. (If pattern matching would be a large help, I might consider Rust).
For C++, there is vcpkg and Conan. While they are overall significantly or much worse options than what Rust offers according to many, in large part due to C++'s cruft and backwards compatibility, they do exist.
Did they change the language? GCC is not meant to change the C or C++ languages (unless the user uses some flag to modify the language), there is an ISO standard that they seek to be compliant with. rustc, on the other hand, only somewhat recently got a specification or something from Ferrocene, and that specification looks lackluster and incomplete from when I last skimmed through it. And rustc does not seem to be developed against the official Rust specification.
And rustc uses LLVM, and has had several bugs as well, whether related to LLVM or just due to itself. But what I linked was intentional breakage, and it caused some people a lot of pain.
Comparing with JS ecosystem is very telling. Some early Rust developers, come from the JS ecosystem (especially at Firefox), and Cargo takes inspiration from the JS ecosystem, like with lock files. But JS ecosystem is a terrible baseline to compare with regarding stability. Comparing a language's stabilitity with JS ecosystem says very little. You should have picked a systems language to compare with.
And your post is itself a part of the Rust community, and it itself is an argument against what you claim in it. If you cannot or will not own up to the 1.80 time crate debacle, or mention the 1.80 time crate debacle proactively as a black mark that weighs on Rust's conscience and that it will take time to rebuild trust and confidence in Rust's stability because of it, well, your priorities, understood as in the Rust community's priorities, are clear, and they do not, in practice, lie with stability, safety and security, nor with being forthcoming.
Your post strongly reinforces Rust's reputation as a language whose language designers are willing to break compatibility on a whim. If Rust proponents argue like this, what breakage will not be forced upon Rust users in the future?
Your post itself reinforces the OP's claim.
Edit: Seriously. At this point, it seems clear that the culture around Rust, especially driven by proponents like you, indirectly have a negative effect on both Rust software, and software security & quality overall, as seen by the bug discussed in the OP. Without your kind of post, would Ubuntu have felt less pressured to make technical management decisions that allowed for the above bug?
It received a lot of attention and "visibility" because it caused a lot of pain to some people. I am befuddled why you would wrongly attempt to dismiss this undeniable counter-example.