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0 pointshu36y ago0 comments

That's not memory safe as the book itself states:

> Now, the volatile accesses are performed automatically through the read and write methods. It's still unsafe to perform writes, but to be fair, hardware is a bunch of mutable state and there's no way for the compiler to know whether these writes are actually safe, so this is a good default position.

https://github.com/rust-embedded/book/blob/9c05a419fc2ad231c...

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clouddrover6y ago

I think you need to read on a bit further. The very next section after the sentence you quoted is:

"We need to wrap this struct up into a higher-layer API that is safe for our users to call. As the driver author, we manually verify the unsafe code is correct, and then present a safe API for our users so they don't have to worry about it (provided they trust us to get it right!)."

Rust lets you write clearly defined unsafe code blocks. It's not a bug, it's a feature:

https://doc.rust-lang.org/book/ch19-01-unsafe-rust.html

https://doc.rust-lang.org/nomicon/index.html

It's worth reading through the whole Embedded Rust book even if you won't be implementing such software. It's interesting.

hu3OP6y ago

Don't assume I haven't read it. I read the book.

Wrapping unsafe code behind an API doesn't make it go away. It's still unsafe and needs manual checking.

Also wrapping code with hints and annotations of some sort is a thing in numerous PL. It's a given, not a feature and certainly not a bug as you wrongly implied I stated.

TLDR: it's still unsafe as the book and others pointed out.

clouddrover6y ago

Then you're misrepresenting what the book is saying, which is worse than not having read it.

As an argument your position makes no sense. You might as well be arguing that there's no point in programming languages because sometimes you have to write assembly.

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0 pointshu36y ago0 comments

That's not memory safe as the book itself states:

https://github.com/rust-embedded/book/blob/9c05a419fc2ad231c...

0 comments

clouddrover6y ago

I think you need to read on a bit further. The very next section after the sentence you quoted is:

Rust lets you write clearly defined unsafe code blocks. It's not a bug, it's a feature:

https://doc.rust-lang.org/book/ch19-01-unsafe-rust.html

https://doc.rust-lang.org/nomicon/index.html

It's worth reading through the whole Embedded Rust book even if you won't be implementing such software. It's interesting.

hu3OP6y ago

Don't assume I haven't read it. I read the book.

Wrapping unsafe code behind an API doesn't make it go away. It's still unsafe and needs manual checking.

Also wrapping code with hints and annotations of some sort is a thing in numerous PL. It's a given, not a feature and certainly not a bug as you wrongly implied I stated.

TLDR: it's still unsafe as the book and others pointed out.

clouddrover6y ago

Then you're misrepresenting what the book is saying, which is worse than not having read it.

As an argument your position makes no sense. You might as well be arguing that there's no point in programming languages because sometimes you have to write assembly.

1 more reply

j / k navigate · click thread line to collapse