`-Z location-detail`: provide option to disable all location details
As reported [here](https://github.com/rust-lang/rust/pull/89920#issuecomment-1190598924), when I first implemented the `-Z location-detail` flag there was a bug, where passing an empty list was not correctly supported, and instead rejected by the compiler. This PR fixes that such that passing an empty list results in no location details being tracked, as originally specified in https://github.com/rust-lang/rfcs/pull/2091 .
This PR also adds a test case to verify that this option continues to work as intended.
Remove implicit names and values from `--cfg` in `--check-cfg`
This PR remove the implicit names and values from `--cfg` in `--check-cfg` because the behavior is quite surprising but also because it's really easy to inadvertently really on the implicitness and when the `--cfg` is not set anymore to have an unexpected warning from an unexpected condition that pass with the implicitness.
This change in behavior will also enable us to warn when an unexpected `--cfg` is passed, ex: the user wrote `--cfg=unstabl` instead of `--cfg=unstable`. The implementation of the warning will be done in a follow-up PR.
cc `@petrochenkov`
Add Fuchsia platform support documentation
This documentation contains instructions for building and running binaries on Fuchsia using its provided SDK.
doc/rustc: describe the uefi target platforms
Add a `platform-support` entry to the rustc-docs for the different `*-unknown-uefi` targets. This describes in detail how this platform works, a few basic examples, and how to compile for the platform.
Red Hat is sponsoring my work on this platform, so I am putting myself down as target maintainer. Co-maintainers are more than welcome to join me in the effort. Communication is going on off-list to coordinate the different efforts.
Note that the ultimate goal is to move the UEFI targets to Tier-2 so bootloaders can be more easily supported in commercial products. This documentation is the first step towards that goal, but should be a viable documentation even for the current Tier-3 status of the targets.
I also want to point out that there is an ongoing GSoC-effort to port the rust standard library to UEFI (by Ayush Singh). While this work is not necessarily required to get to Tier-2, we definitely should coordinate the efforts and update the documentation as soon as any such ports are merged.
Note that the targets are already used by multiple commercial and non commercial production systems, including, but not limited to:
* Tianocore-EDK2 (Official UEFI SDK by Intel) comes with rust support
in its staging repository (not part of any release, yet).
(https://github.com/tianocore/edk2-staging/tree)
* Intel's research program "Project Mu" uses the rust UEFI targets to
show possible future replacements for Tianocore-EDK2.
* The Rust OS "Redox" uses the UEFI targets for its bootloader.
(https://www.redox-os.org/)
* The hugely popular in-depth documentation of OS development in Rust
by Philipp Oppermann uses the UEFI targets.
(https://os.phil-opp.com/)
Prior to this fix, `-Z location-detail` provided no mechanism for
disabling all location details. This commit also adds a test case
to verify that this option continues to work as intended, and
clarifies the documentation of this option.
Add a `platform-support` entry to the rustc-docs for the different
`*-unknown-uefi` targets. This describes in detail how this platform
works, a few basic examples, and how to compile for the platform.
Red Hat is sponsoring my work on this platform, so I am putting myself
down as target maintainer. Co-maintainers are more than welcome to join
me in the effort. Communication is going on off-list to coordinate the
different efforts.
Note that the ultimate goal is to move the UEFI targets to Tier-2 so
bootloaders can be more easily supported in commercial products. This
documentation is the first step towards that goal, but should be a
viable documentation even for the current Tier-3 status of the targets.
I also want to point out that there is an ongoing GSoC-effort to port
the rust standard library to UEFI (by Ayush Singh). While this work is
not necessarily required to get to Tier-2, we definitely should
coordinate the efforts and update the documentation as soon as any such
ports are merged.
Note that the targets are already used by multiple commercial and non
commercial production systems, including, but not limited to:
* Tianocore-EDK2 (Official UEFI SDK by Intel) comes with rust support
in its staging repository (not part of any release, yet).
(https://github.com/tianocore/edk2-staging/tree)
* Intel's research program "Project Mu" uses the rust UEFI targets to
show possible future replacements for Tianocore-EDK2.
* The Rust OS "Redox" uses the UEFI targets for its bootloader.
(https://www.redox-os.org/)
* The hugely popular in-depth documentation of OS development in Rust
by Philipp Oppermann uses the UEFI targets.
(https://os.phil-opp.com/)
Signed-off-by: David Rheinsberg <david.rheinsberg@gmail.com>
Add fine-grained LLVM CFI support to the Rust compiler
This PR improves the LLVM Control Flow Integrity (CFI) support in the Rust compiler by providing forward-edge control flow protection for Rust-compiled code only by aggregating function pointers in groups identified by their return and parameter types.
Forward-edge control flow protection for C or C++ and Rust -compiled code "mixed binaries" (i.e., for when C or C++ and Rust -compiled code share the same virtual address space) will be provided in later work as part of this project by identifying C char and integer type uses at the time types are encoded (see Type metadata in the design document in the tracking issue https://github.com/rust-lang/rust/issues/89653).
LLVM CFI can be enabled with -Zsanitizer=cfi and requires LTO (i.e., -Clto).
Thank you again, `@eddyb,` `@nagisa,` `@pcc,` and `@tmiasko` for all the help!
Add support for LLVM ShadowCallStack.
LLVMs ShadowCallStack provides backward edge control flow integrity protection by using a separate shadow stack to store and retrieve a function's return address.
LLVM currently only supports this for AArch64 targets. The x18 register is used to hold the pointer to the shadow stack, and therefore this only works on ABIs which reserve x18. Further details are available in the [LLVM ShadowCallStack](https://clang.llvm.org/docs/ShadowCallStack.html) docs.
# Usage
`-Zsanitizer=shadow-call-stack`
# Comments/Caveats
* Currently only enabled for the aarch64-linux-android target
* Requires the platform to define a runtime to initialize the shadow stack, see the [LLVM docs](https://clang.llvm.org/docs/ShadowCallStack.html) for more detail.
Build the Clippy book as part of x.py doc
r? ``@ehuss`` since you said you would be interested in helping moving this forward.
cc ``@jyn514`` as part of the bootstrap team.
DWARF version 5 brings a number of improvements over version 4. Quoting from
the announcement [1]:
> Version 5 incorporates improvements in many areas: better data compression,
> separation of debugging data from executable files, improved description of
> macros and source files, faster searching for symbols, improved debugging
> optimized code, as well as numerous improvements in functionality and
> performance.
On platforms where DWARF version 5 is supported (Linux, primarily), this commit
adds support for it behind a new `-Z dwarf-version=5` flag.
[1]: https://dwarfstd.org/Public_Review.php
Document unstable `--extern` options
These are needed for Cargo's `build-std` feature and for anyone who wanted to do a similar thing outside of Cargo.
Remove dereferencing of Box from codegen
Through #94043, #94414, #94873, and #95328, I've been fixing issues caused by Box being treated like a pointer when it is not a pointer. However, these PRs just introduced special cases for Box. This PR removes those special cases and instead transforms a deref of Box into a deref of the pointer it contains.
Hopefully, this is the end of the Box<T, A> ICEs.
STD support for the Nintendo 3DS
Rustc already supports compiling for the Nintendo 3DS using the `armv6k-nintendo-3ds` target (Tier 3). Until now though, only `core` and `alloc` were supported. This PR adds standard library support for the Nintendo 3DS. A notable exclusion is `std::thread` support, which will come in a follow-up PR as it requires more complicated changes.
This has been a joint effort by `@Meziu,` `@ian-h-chamberlain,` myself, and prior work by `@rust3ds` members.
### Background
The Nintendo 3DS (Horizon OS) is a mostly-UNIX looking system, with the caveat that it does not come with a full libc implementation out of the box. On the homebrew side (I'm not under NDA), the libc interface is partially implemented by the [devkitPro](https://devkitpro.org/wiki/devkitPro_pacman) toolchain and a user library like [`libctru`](https://github.com/devkitPro/libctru). This is important because there are [some possible legal barriers](https://github.com/rust-lang/rust/pull/88529#issuecomment-919938396) to linking directly to a library that uses the underlying platform APIs, since they might be considered a trade secret or under NDA.
To get around this, the standard library impl for the 3DS does not directly depend on any platform-level APIs. Instead, it expects standard libc functions to be linked in. The implementation of these libc functions is left to the user. Some functions are provided by the devkitPro toolchain, but in our testing, we used the following to fill in the other functions:
- [`libctru`] - provides more basic APIs, such as `nanosleep`. Linked in by way of [`ctru-sys`](https://github.com/Meziu/ctru-rs/tree/master/ctru-sys).
- [`pthread-3ds`](https://github.com/Meziu/pthread-3ds) - provides pthread APIs for `std::thread`. Implemented using [`libctru`].
- [`linker-fix-3ds`](https://github.com/Meziu/rust-linker-fix-3ds) - fulfills some other missing libc APIs. Implemented using [`libctru`].
For more details, see the `src/doc/rustc/src/platform-support/armv6k-nintendo-3ds.md` file added in this PR.
### Notes
We've already upstreamed changes to the [`libc`] crate to support this PR, as well as the upcoming threading PR. These changes have all been released as of 0.2.121, so we bump the crate version in this PR.
Edit: After some rebases, the version bump has already been merged so it doesn't appear in this PR.
A lot of the changes in this PR are straightforward, and follow in the footsteps of the ESP-IDF target: https://github.com/rust-lang/rust/pull/87666.
The 3DS does not support user space process spawning, so these APIs are unimplemented (similar to ESP-IDF).
[`libctru`]: https://github.com/devkitPro/libctru
[`libc`]: https://github.com/rust-lang/libc
Add Apple WatchOS compile targets
Hello,
I would like to add the following target triples for Apple WatchOS as Tier 3 platforms:
armv7k-apple-watchos
arm64_32-apple-watchos
x86_64-apple-watchos-sim
There are some pre-requisites Pull Requests:
https://github.com/rust-lang/compiler-builtins/pull/456 (merged)
https://github.com/alexcrichton/cc-rs/pull/662 (pending)
https://github.com/rust-lang/libc/pull/2717 (merged)
There will be a subsequent PR with standard library changes for WatchOS. Previous compiler and library changes were in a single PR (https://github.com/rust-lang/rust/pull/94736) which is now closed in favour of separate PRs.
Many thanks!
Vlad.
### Tier 3 Target Requirements
Adds support for Apple WatchOS compile targets.
Below are details on how this target meets the requirements for tier 3:
> tier 3 target must have a designated developer or developers (the "target maintainers") on record to be CCed when issues arise regarding the target. (The mechanism to track and CC such developers may evolve over time.)
`@deg4uss3r` has volunteered to be the target maintainer. I am also happy to help if a second maintainer is required.
> Targets must use naming consistent with any existing targets; for instance, a target for the same CPU or OS as an existing Rust target should use the same name for that CPU or OS. Targets should normally use the same names and naming conventions as used elsewhere in the broader ecosystem beyond Rust (such as in other toolchains), unless they have a very good reason to diverge. Changing the name of a target can be highly disruptive, especially once the target reaches a higher tier, so getting the name right is important even for a tier 3 target.
Uses the same naming as the LLVM target, and the same convention as other Apple targets.
> Target names should not introduce undue confusion or ambiguity unless absolutely necessary to maintain ecosystem compatibility. For example, if the name of the target makes people extremely likely to form incorrect beliefs about what it targets, the name should be changed or augmented to disambiguate it.
I don't believe there is any ambiguity here.
> Tier 3 targets may have unusual requirements to build or use, but must not create legal issues or impose onerous legal terms for the Rust project or for Rust developers or users.
I don't see any legal issues here.
> The target must not introduce license incompatibilities.
> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
> The target must not cause the Rust tools or libraries built for any other host (even when supporting cross-compilation to the target) to depend on any new dependency less permissive than the Rust licensing policy. This applies whether the dependency is a Rust crate that would require adding new license exceptions (as specified by the tidy tool in the rust-lang/rust repository), or whether the dependency is a native library or binary. In other words, the introduction of the target must not cause a user installing or running a version of Rust or the Rust tools to be subject to any new license requirements.
> If the target supports building host tools (such as rustc or cargo), those host tools must not depend on proprietary (non-FOSS) libraries, other than ordinary runtime libraries supplied by the platform and commonly used by other binaries built for the target. For instance, rustc built for the target may depend on a common proprietary C runtime library or console output library, but must not depend on a proprietary code generation library or code optimization library. Rust's license permits such combinations, but the Rust project has no interest in maintaining such combinations within the scope of Rust itself, even at tier 3.
> Targets should not require proprietary (non-FOSS) components to link a functional binary or library.
> "onerous" here is an intentionally subjective term. At a minimum, "onerous" legal/licensing terms include but are not limited to: non-disclosure requirements, non-compete requirements, contributor license agreements (CLAs) or equivalent, "non-commercial"/"research-only"/etc terms, requirements conditional on the employer or employment of any particular Rust developers, revocable terms, any requirements that create liability for the Rust project or its developers or users, or any requirements that adversely affect the livelihood or prospects of the Rust project or its developers or users.
I see no issues with any of the above.
> Neither this policy nor any decisions made regarding targets shall create any binding agreement or estoppel by any party. If any member of an approving Rust team serves as one of the maintainers of a target, or has any legal or employment requirement (explicit or implicit) that might affect their decisions regarding a target, they must recuse themselves from any approval decisions regarding the target's tier status, though they may otherwise participate in discussions.
> This requirement does not prevent part or all of this policy from being cited in an explicit contract or work agreement (e.g. to implement or maintain support for a target). This requirement exists to ensure that a developer or team responsible for reviewing and approving a target does not face any legal threats or obligations that would prevent them from freely exercising their judgment in such approval, even if such judgment involves subjective matters or goes beyond the letter of these requirements.
Only relevant to those making approval decisions.
> Tier 3 targets should attempt to implement as much of the standard libraries as possible and appropriate (core for most targets, alloc for targets that can support dynamic memory allocation, std for targets with an operating system or equivalent layer of system-provided functionality), but may leave some code unimplemented (either unavailable or stubbed out as appropriate), whether because the target makes it impossible to implement or challenging to implement. The authors of pull requests are not obligated to avoid calling any portions of the standard library on the basis of a tier 3 target not implementing those portions.
core and alloc can be used. std support will be added in a subsequent PR.
> The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible. If the target supports running tests (even if they do not pass), the documentation must explain how to run tests for the target, using emulation if possible or dedicated hardware if necessary.
Use --target=<target> option to cross compile, just like any target. Tests can be run using the WatchOS simulator (see https://developer.apple.com/documentation/xcode/running-your-app-in-the-simulator-or-on-a-device).
> Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target. In particular, do not post comments (automated or manual) on a PR that derail or suggest a block on the PR based on a tier 3 target. Do not send automated messages or notifications (via any medium, including via `@)` to a PR author or others involved with a PR regarding a tier 3 target, unless they have opted into such messages.
> Backlinks such as those generated by the issue/PR tracker when linking to an issue or PR are not considered a violation of this policy, within reason. However, such messages (even on a separate repository) must not generate notifications to anyone involved with a PR who has not requested such notifications.
I don't foresee this being a problem.
> Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
> In particular, this may come up when working on closely related targets, such as variations of the same architecture with different features. Avoid introducing unconditional uses of features that another variation of the target may not have; use conditional compilation or runtime detection, as appropriate, to let each target run code supported by that target.
No other targets should be affected by the pull request.
Update #[doc(html_playground_url)] documentation to mention what the request will be
The [documentation for `#![doc(html_playground_url = "_")]`](https://doc.rust-lang.org/rustdoc/write-documentation/the-doc-attribute.html#html_playground_url) specifies that a request will be made to the given URL but does specify what the contents of the request will be. This PR updates the documentation to include the query parameters through which the code is provided to the playground.
Add support for embedding pretty printers via `#[debugger_visualizer]` attribute
Initial support for [RFC 3191](https://github.com/rust-lang/rfcs/pull/3191) in PR https://github.com/rust-lang/rust/pull/91779 was scoped to supporting embedding NatVis files using a new attribute. This PR implements the pretty printer support as stated in the RFC mentioned above.
This change includes embedding pretty printers in the `.debug_gdb_scripts` just as the pretty printers for rustc are embedded today. Also added additional tests for embedded pretty printers. Additionally cleaned up error checking so all error checking is done up front regardless of the current target.
RFC: https://github.com/rust-lang/rfcs/pull/3191
Ensure all error checking for `#[debugger_visualizer]` is done up front and not when the `debugger_visualizer` query is run.
Clean up potential ODR violations when embedding pretty printers into the `__rustc_debug_gdb_scripts_section__` section.
Respond to PR comments and update documentation.