3 ms·

Rust has no stable ABI contrary to C and also support much higher concept like polymorphism or high order functions which are much harder to represent in a simp

by adev_ 6y ago

Rust has no stable ABI contrary to C and also support much higher concept like polymorphism or high order functions which are much harder to represent in a simple ABI. Real dynamic linking on that (dlopen-style) can be a real nightmare, specially between compiler versions. You can also add that Rust do not have a runtime, which is in many cases an advantage, but also tend to make libraries bigger.

Groxx 6y ago
Similar to C++ though, e.g. explosions of template expansions, you don't have to use those higher-level and harder-to-keep-concise features. Other fancy languages have stable ABIs, it's not impossible, nor does it require that it's complex to use. Though the average one is probably harder, yes. I'd wager that it's mostly lack of care or motivation though, made a bit worse by common language features.
- adev_ 6y ago
  > Similar to C++ though, e.g. explosions of template expansions, you don't have to use those higher-level and harder-to-keep-concise features. C++ has a stable ABI. Fragile, but stable. Or doing things like updating libQt on your Linux distribution without recompiling half of the world would be close to impossible :)
  - amaranth 6y ago
    This is a relatively new feature and there have been one or two ABI breaks since they thought it was done that required recompiling half the world. I think it's been solid for at least most of the last decade though so... stable enough? I'm not sure if there is an actual spec somewhere though, certainly not a proper one from a standards body. It's just "whatever GCC or MSVC do on that OS/CPU combo" and those two happen to have stopped changing the ABI every compiling release at some point. They're both at least based on the relatively well specified Itanium C++ ABI though so that helps.
  - Groxx 6y ago
    C++ is also older than Rust by, oh... a few years. I'm not aware of any plan to not stabilize Rust's ABI, it just hasn't happened yet. It's completely fair to label that a deal-breaker for using Rust, but trying to draw a hypothetical box around it with the label "its ABI will be difficult to create and/or use" seems a bit unwarranted.
devit 6y ago
Rust can create dynamic libraries that import and export symbols using the C ABI, so it is not worse than C in such a comparisons, since it can do exactly the same thing as C.
- CameronNemo 6y ago
  Are there any examples of libraries that are implemented in this way?
  - the_why_of_y 6y ago
    https://news.ycombinator.com/item?id=23290506 https://news.ycombinator.com/item?id=23290506 https://coaxion.net/blog/2017/09/exporting-a-gobject-c-api-from-rust-code-and-using-it-from-c-python-javascript-and-others/ https://coaxion.net/blog/2017/09/exporting-a-gobject-c-api-f... https://hsivonen.fi/modern-cpp-in-rust/ https://hsivonen.fi/modern-cpp-in-rust/ http://hansihe.com/2017/02/05/rustler-safe-erlang-elixir-nifs-in-rust.html http://hansihe.com/2017/02/05/rustler-safe-erlang-elixir-nif...
erlend_sh 6y ago
Recently there’s been a renewed discussion about how to make a stable, modular ABI for Rust: https://internals.rust-lang.org/t/a-stable-modular-abi-for-rust/12347?u=erlend_sh https://internals.rust-lang.org/t/a-stable-modular-abi-for-r...

by adev_ 6y ago

Groxx 6y ago

Similar to C++ though, e.g. explosions of template expansions, you don't have to use those higher-level and harder-to-keep-concise features. Other fancy languages have stable ABIs, it's not impossible, nor does it require that it's complex to use. Though the average one is probably harder, yes. I'd wager that it's mostly lack of care or motivation though, made a bit worse by common language features.

adev_ 6y ago
> Similar to C++ though, e.g. explosions of template expansions, you don't have to use those higher-level and harder-to-keep-concise features. C++ has a stable ABI. Fragile, but stable. Or doing things like updating libQt on your Linux distribution without recompiling half of the world would be close to impossible :)
- amaranth 6y ago
  This is a relatively new feature and there have been one or two ABI breaks since they thought it was done that required recompiling half the world. I think it's been solid for at least most of the last decade though so... stable enough? I'm not sure if there is an actual spec somewhere though, certainly not a proper one from a standards body. It's just "whatever GCC or MSVC do on that OS/CPU combo" and those two happen to have stopped changing the ABI every compiling release at some point. They're both at least based on the relatively well specified Itanium C++ ABI though so that helps.
- Groxx 6y ago
  C++ is also older than Rust by, oh... a few years. I'm not aware of any plan to not stabilize Rust's ABI, it just hasn't happened yet. It's completely fair to label that a deal-breaker for using Rust, but trying to draw a hypothetical box around it with the label "its ABI will be difficult to create and/or use" seems a bit unwarranted.

devit 6y ago

Rust can create dynamic libraries that import and export symbols using the C ABI, so it is not worse than C in such a comparisons, since it can do exactly the same thing as C.

CameronNemo 6y ago
Are there any examples of libraries that are implemented in this way?
- the_why_of_y 6y ago
  https://news.ycombinator.com/item?id=23290506 https://news.ycombinator.com/item?id=23290506 https://coaxion.net/blog/2017/09/exporting-a-gobject-c-api-from-rust-code-and-using-it-from-c-python-javascript-and-others/ https://coaxion.net/blog/2017/09/exporting-a-gobject-c-api-f... https://hsivonen.fi/modern-cpp-in-rust/ https://hsivonen.fi/modern-cpp-in-rust/ http://hansihe.com/2017/02/05/rustler-safe-erlang-elixir-nifs-in-rust.html http://hansihe.com/2017/02/05/rustler-safe-erlang-elixir-nif...

erlend_sh 6y ago

Recently there’s been a renewed discussion about how to make a stable, modular ABI for Rust: https://internals.rust-lang.org/t/a-stable-modular-abi-for-rust/12347?u=erlend_sh https://internals.rust-lang.org/t/a-stable-modular-abi-for-r...