JOjohnisgood·Nov 21, 2025
Why would Rust need formal verification tools like https://github.com/rust-lang/miri if the programming language is so safe that it prevents them[1]?!
[1] Undefined Behaviors.
In The Lions Operating Systemrust-lang
miri
Rust2016–2026
rust-lang / miri
miri
An interpreter for Rust's mid-level intermediate representation
33Distinct people
41Mentions
1Explicit recommenders
6.7KGitHub stars
What to know before exploring
What it is
An interpreter for Rust's mid-level intermediate representation
GitHub
Where it is used
No documented product use was verified in the last source check.
What people are saying
If you have a codebase that uses unsafe, I highly recommend running your tests through Miri (cargo miri nextest) and seeing what spills out. I ran tests for a codebase at work…
landr0id used a recommendation phrase. One indexed comment matches. This is a phrase match, not a verdict.
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Also in these discussions
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This week on Hacker News
Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 11:19:25 AM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by year41 dated mentions
Observed mentions: 2016-03-04 11:38:42 UTC to 2026-09-17 14:02:35 UTC.
* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2016 | 2016-01-01 00:00:00 UTC | 2017-01-01 00:00:00 UTC | 7 | 0 | 7 |
| 2017 | 2017-01-01 00:00:00 UTC | 2018-01-01 00:00:00 UTC | 4 | 0 | 4 |
| 2018 | 2018-01-01 00:00:00 UTC | 2019-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2019 | 2019-01-01 00:00:00 UTC | 2020-01-01 00:00:00 UTC | 2 | 1 | 1 |
| 2020 | 2020-01-01 00:00:00 UTC | 2021-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 3 | 0 | 3 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 4 | 0 | 4 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 5 | 0 | 5 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 6 | 1 | 5 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 5 | 0 | 5 |
What Hacker News says
6 sourcesDefinite Rust bugs found by the Miri UB detector
3 points · Open discussionIt does have an interpreter for the full language, that's what Miri uses [0]. In fact, Miri doesn't even have its own evaluator, it just adds additional features to the rustc const-evaluation. The big limitations are that it doesn't have much support for syscalls or other calls into non-Rust code, and it emulates all multithreaded code on a single thread.
[0] https://github.com/rust-lang/miri
In Why Cargo Check Is So SlowHere's the implementation in Miri for those interested: https://github.com/rust-lang/miri/tree/master/src/borrow_tra...
In Tree Borrows> C debuggers and tooling are vastly more powerful than Rust's static type system, and catch a much wider array of memory problems (, and bugs) than the Rust compiler can catch. Static verification is far more limited than the dynamic verification a sophisticated debugger can perform.
Is there any dynamic verifier that fully validates all acesses w.r.t. the object trees specified by the C standard? Tools like ASan and UBSan won't detect a write to one field running into another field, only a write overrunning the complete object. (Compiler-level hardening might catch that to some extent, but it's limited to TU boundaries.) Not to mention things like 'misuse of restrict pointers' that I've never seen any verifiers for, except for special cases like overlapping memcpy() buffers.
Meanwhile, Rust does have its own dynamic verifier, called Mir
Read the rest
i [0], which checks just about every language-level rule at runtime. The main drawbacks are that it's slow and doesn't support calling arbitrary C functions, but it would be hard to get that to work short of the Valgrind route of emulating the whole process on an instruction level.
[0] https://github.com/rust-lang/miri
Miri is a Rust tool with a similar function to Valgrind, it checks for undefined behavior.
https://github.com/rust-lang/miri
In Rhai: An embedded scripting language for Rust