ikos VS tock

I beg to differ: there are a few tools which are comparable.

Frama-C (https://www.frama-c.com) is an open source framework that has, among its analyzers, one based on abstract interpretation (https://www.frama-c.com/fc-plugins/eva.html) that is very similar in spirit to Astree.

MOPSA (https://mopsa.lip6.fr) is another open-source project (albeit more recent, and in a more "academic" stage) that also provides abstract interpretation to analyze C programs for flaws.

NASA also released IKOS (https://github.com/NASA-SW-VnV/ikos), on the same vein.

Of course they lack the polish of a product which costs tens of thousands of euros per license, but they are open source, and their purpose is the same: to ensure code safety via formal methods, in particular abstract interpretation.

It is possible to get these tools to analyze some code and generate no complaints, which ensures absence of several kinds of problems, such as memory safety issues.

Then again, it's hard to know exactly how much they differ from Astree, since you need a license to compare them, and I don't even know if you are allowed to publish such comparisons.

I've been playing around with running IKOS (https://github.com/NASA-SW-VnV/ikos), it sounds very cool but doesn't seem to be super well maintained. I've managed to compile my project to llvm bit-code and run the IKSO on it, but the actual analysis seems to be buggy. There are open issues for the problems I encountered, but the make the analysis pretty useless (it thinks most functions are unreachable).

> https://www.absint.com/astree/index.htm

This looks interesting. It's based on abstract interpretation which is more or less the most powerful approach for imperative code available. (Because the way it works it's likely slow as hell though, I guess).

But it's closed source. One of this kind of products where you need to asks for the price… I think we all know what this means: It'll be laughably expensive.

I don't see any offer for OpenSource projects frankly.

> https://github.com/NASA-SW-VnV/ikos

Also abstract interpretation based. Looks less polished than the first one at first glance.

It's under some questionable license. According to OSI it's OpenSource. According to the FSF it's not. (The FSF argument sounds strong. They're right in my opinion. This NASA license does not look like OpenSource).

But an OpenSource project could use it for free I assume.

> https://github.com/static-analysis-engineering/CodeHawk-C

Much more constrained in scope than the other ones. But looks a little bit "too academic" imho: Uses its own C parser and such.

At least it's OpenSource under MIT license.

Thanks for the links either way! Good to know about some tools in case one would need them at some point.

> I have planned to try using them on OpenZFS for a while, but I am still busy reviewing and fixing reports made by conventional static analyzers.

Stupid question about usual C development practices (as I don't have much contact with that):

Aren't analyzers today part of the build pipeline form the get go? Especially as C is known to be full of booby traps.

Imho it shouldn't be even possible to push anything that has issues discovered by tools.

This should be the lowest barrier as most code analyzers are at most able to spot quite obvious problems (the commercial one above is likely an exception to this "rule"). When even the usual "stupid analyzer" sees issues than the code is very likely in a very bad shape.

Adding such tools later on in the development is like activating warnings post factum: You'll get drowned in issues.

Especially in such critical domains as file-systems I would actually expect that the developers are using "the best tools money can buy" (or at least the best OpenSource tools available).

"Still fixing bugs found by some code analyzer" doesn't sound like someone should have much trust with their data in something like ZFS, to be honest… The statement sounds actually quite scary to me.

They have very unusual license which I have never seen before: https://github.com/NASA-SW-VnV/ikos/blob/master/LICENSE.txt

Is anyone familiar with it? Is it OSI certified? (it's not on the OSI's site).

Yeah there are tools that require adding contracts as comments. But again, there are also friction-less tools that don't require any changes (for example a NASA one).

Hi! This is Daniel from OxidOS Automotive (stating this for disclaimer purposes).

Yes, our OS is based on TockOS, and our CEO (Alex Radovici) is #7 in the contributors list (https://github.com/tock/tock/graphs/contributors), with other colleagues contributing in the past years.

I'm definitely not the best person to answer this, but honestly it's not bad. Here's an example of a moderately complex peripheral, the cortex-m MPU, and how one rust OS handles it:

https://github.com/tock/tock/blob/3a0527d586702b8ae8cb242391...

Reads and writes turn into volatile reads, so everything works out under the hood. You get the benefits of everything having good names, declared sizes, and proper typing on your register accesses. You can extend that to bit accesses as well.

Rust still has a few areas it isn't competitive in, like your hyper limited or obscure chips (e.g. 8051s, XAP), mature tooling around formal methods, and a certification story for safety critical code. People are working on these latter two issues (e.g. ferrocene) and supposedly very close to public delivery, but you know how slow the industry is to adopt new things even then.

There's Tock (https://www.tockos.org/), which is written in Rust (with sprinkles of assembly).

Yeah, and I like I mentioned in the earlier comment, omitting the frame pointer reduces code size by 10% on RISC-V targets, which is huge when dealing with embedded flash: https://github.com/tock/tock/pull/1660

Tock is an excellent embedded OS written in Rust and has some good industrial support. I think Tock gets a lot of stuff right and I highly recommend some of the talks the developers gave on it.

Unfortunately, it increases the code size by 10%. I was looking into this just last week, and can confirm that it's still a problem on the latest version of Rust nightly: https://github.com/tock/tock/pull/1660

I wish we could have frame pointers, because they would make working in embedded land so much easier and more reliable, but a 10% increase in code size just isn't worth it.

TockOS was the first rust RTOS I found. Coincidentally, it has had support for the esp32c3 for over a year now.