rust/library/panic_unwind/Cargo.toml

19 lines
359 B
TOML
Raw Normal View History

rustc: Implement custom panic runtimes This commit is an implementation of [RFC 1513] which allows applications to alter the behavior of panics at compile time. A new compiler flag, `-C panic`, is added and accepts the values `unwind` or `panic`, with the default being `unwind`. This model affects how code is generated for the local crate, skipping generation of landing pads with `-C panic=abort`. [RFC 1513]: https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md Panic implementations are then provided by crates tagged with `#![panic_runtime]` and lazily required by crates with `#![needs_panic_runtime]`. The panic strategy (`-C panic` value) of the panic runtime must match the final product, and if the panic strategy is not `abort` then the entire DAG must have the same panic strategy. With the `-C panic=abort` strategy, users can expect a stable method to disable generation of landing pads, improving optimization in niche scenarios, decreasing compile time, and decreasing output binary size. With the `-C panic=unwind` strategy users can expect the existing ability to isolate failure in Rust code from the outside world. Organizationally, this commit dismantles the `sys_common::unwind` module in favor of some bits moving part of it to `libpanic_unwind` and the rest into the `panicking` module in libstd. The custom panic runtime support is pretty similar to the custom allocator support with the only major difference being how the panic runtime is injected (takes the `-C panic` flag into account).
2016-04-09 01:18:40 +02:00
[package]
authors = ["The Rust Project Developers"]
name = "panic_unwind"
version = "0.0.0"
2019-02-02 19:00:02 +01:00
edition = "2018"
rustc: Implement custom panic runtimes This commit is an implementation of [RFC 1513] which allows applications to alter the behavior of panics at compile time. A new compiler flag, `-C panic`, is added and accepts the values `unwind` or `panic`, with the default being `unwind`. This model affects how code is generated for the local crate, skipping generation of landing pads with `-C panic=abort`. [RFC 1513]: https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md Panic implementations are then provided by crates tagged with `#![panic_runtime]` and lazily required by crates with `#![needs_panic_runtime]`. The panic strategy (`-C panic` value) of the panic runtime must match the final product, and if the panic strategy is not `abort` then the entire DAG must have the same panic strategy. With the `-C panic=abort` strategy, users can expect a stable method to disable generation of landing pads, improving optimization in niche scenarios, decreasing compile time, and decreasing output binary size. With the `-C panic=unwind` strategy users can expect the existing ability to isolate failure in Rust code from the outside world. Organizationally, this commit dismantles the `sys_common::unwind` module in favor of some bits moving part of it to `libpanic_unwind` and the rest into the `panicking` module in libstd. The custom panic runtime support is pretty similar to the custom allocator support with the only major difference being how the panic runtime is injected (takes the `-C panic` flag into account).
2016-04-09 01:18:40 +02:00
[lib]
test = false
bench = false
doc = false
rustc: Implement custom panic runtimes This commit is an implementation of [RFC 1513] which allows applications to alter the behavior of panics at compile time. A new compiler flag, `-C panic`, is added and accepts the values `unwind` or `panic`, with the default being `unwind`. This model affects how code is generated for the local crate, skipping generation of landing pads with `-C panic=abort`. [RFC 1513]: https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md Panic implementations are then provided by crates tagged with `#![panic_runtime]` and lazily required by crates with `#![needs_panic_runtime]`. The panic strategy (`-C panic` value) of the panic runtime must match the final product, and if the panic strategy is not `abort` then the entire DAG must have the same panic strategy. With the `-C panic=abort` strategy, users can expect a stable method to disable generation of landing pads, improving optimization in niche scenarios, decreasing compile time, and decreasing output binary size. With the `-C panic=unwind` strategy users can expect the existing ability to isolate failure in Rust code from the outside world. Organizationally, this commit dismantles the `sys_common::unwind` module in favor of some bits moving part of it to `libpanic_unwind` and the rest into the `panicking` module in libstd. The custom panic runtime support is pretty similar to the custom allocator support with the only major difference being how the panic runtime is injected (takes the `-C panic` flag into account).
2016-04-09 01:18:40 +02:00
[dependencies]
2020-06-12 04:31:49 +02:00
alloc = { path = "../alloc" }
core = { path = "../core" }
std: Depend directly on crates.io crates Ever since we added a Cargo-based build system for the compiler the standard library has always been a little special, it's never been able to depend on crates.io crates for runtime dependencies. This has been a result of various limitations, namely that Cargo doesn't understand that crates from crates.io depend on libcore, so Cargo tries to build crates before libcore is finished. I had an idea this afternoon, however, which lifts the strategy from #52919 to directly depend on crates.io crates from the standard library. After all is said and done this removes a whopping three submodules that we need to manage! The basic idea here is that for any crate `std` depends on it adds an *optional* dependency on an empty crate on crates.io, in this case named `rustc-std-workspace-core`. This crate is overridden via `[patch]` in this repository to point to a local crate we write, and *that* has a `path` dependency on libcore. Note that all `no_std` crates also depend on `compiler_builtins`, but if we're not using submodules we can publish `compiler_builtins` to crates.io and all crates can depend on it anyway! The basic strategy then looks like: * The standard library (or some transitive dep) decides to depend on a crate `foo`. * The standard library adds ```toml [dependencies] foo = { version = "0.1", features = ['rustc-dep-of-std'] } ``` * The crate `foo` has an optional dependency on `rustc-std-workspace-core` * The crate `foo` has an optional dependency on `compiler_builtins` * The crate `foo` has a feature `rustc-dep-of-std` which activates these crates and any other necessary infrastructure in the crate. A sample commit for `dlmalloc` [turns out to be quite simple][commit]. After that all `no_std` crates should largely build "as is" and still be publishable on crates.io! Notably they should be able to continue to use stable Rust if necessary, since the `rename-dependency` feature of Cargo is soon stabilizing. As a proof of concept, this commit removes the `dlmalloc`, `libcompiler_builtins`, and `libc` submodules from this repository. Long thorns in our side these are now gone for good and we can directly depend on crates.io! It's hoped that in the long term we can bring in other crates as necessary, but for now this is largely intended to simply make it easier to manage these crates and remove submodules. This should be a transparent non-breaking change for all users, but one possible stickler is that this almost for sure breaks out-of-tree `std`-building tools like `xargo` and `cargo-xbuild`. I think it should be relatively easy to get them working, however, as all that's needed is an entry in the `[patch]` section used to build the standard library. Hopefully we can work with these tools to solve this problem! [commit]: https://github.com/alexcrichton/dlmalloc-rs/commit/28ee12db813a3b650a7c25d1c36d2c17dcb88ae3
2018-11-20 06:52:50 +01:00
libc = { version = "0.2", default-features = false }
2020-06-12 04:31:49 +02:00
unwind = { path = "../unwind" }
std: Depend directly on crates.io crates Ever since we added a Cargo-based build system for the compiler the standard library has always been a little special, it's never been able to depend on crates.io crates for runtime dependencies. This has been a result of various limitations, namely that Cargo doesn't understand that crates from crates.io depend on libcore, so Cargo tries to build crates before libcore is finished. I had an idea this afternoon, however, which lifts the strategy from #52919 to directly depend on crates.io crates from the standard library. After all is said and done this removes a whopping three submodules that we need to manage! The basic idea here is that for any crate `std` depends on it adds an *optional* dependency on an empty crate on crates.io, in this case named `rustc-std-workspace-core`. This crate is overridden via `[patch]` in this repository to point to a local crate we write, and *that* has a `path` dependency on libcore. Note that all `no_std` crates also depend on `compiler_builtins`, but if we're not using submodules we can publish `compiler_builtins` to crates.io and all crates can depend on it anyway! The basic strategy then looks like: * The standard library (or some transitive dep) decides to depend on a crate `foo`. * The standard library adds ```toml [dependencies] foo = { version = "0.1", features = ['rustc-dep-of-std'] } ``` * The crate `foo` has an optional dependency on `rustc-std-workspace-core` * The crate `foo` has an optional dependency on `compiler_builtins` * The crate `foo` has a feature `rustc-dep-of-std` which activates these crates and any other necessary infrastructure in the crate. A sample commit for `dlmalloc` [turns out to be quite simple][commit]. After that all `no_std` crates should largely build "as is" and still be publishable on crates.io! Notably they should be able to continue to use stable Rust if necessary, since the `rename-dependency` feature of Cargo is soon stabilizing. As a proof of concept, this commit removes the `dlmalloc`, `libcompiler_builtins`, and `libc` submodules from this repository. Long thorns in our side these are now gone for good and we can directly depend on crates.io! It's hoped that in the long term we can bring in other crates as necessary, but for now this is largely intended to simply make it easier to manage these crates and remove submodules. This should be a transparent non-breaking change for all users, but one possible stickler is that this almost for sure breaks out-of-tree `std`-building tools like `xargo` and `cargo-xbuild`. I think it should be relatively easy to get them working, however, as all that's needed is an entry in the `[patch]` section used to build the standard library. Hopefully we can work with these tools to solve this problem! [commit]: https://github.com/alexcrichton/dlmalloc-rs/commit/28ee12db813a3b650a7c25d1c36d2c17dcb88ae3
2018-11-20 06:52:50 +01:00
compiler_builtins = "0.1.0"
cfg-if = "0.1.8"