Add LLVM KCFI support to the Rust compiler
This PR adds LLVM Kernel Control Flow Integrity (KCFI) support to the Rust compiler. It initially provides forward-edge control flow protection for operating systems kernels for Rust-compiled code only by aggregating function pointers in groups identified by their return and parameter types. (See llvm/llvm-project@cff5bef.)
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 #89653).
LLVM KCFI can be enabled with -Zsanitizer=kcfi.
Thank you again, `@bjorn3,` `@eddyb,` `@nagisa,` and `@ojeda,` for all the help!
Mangle "main" as "__main_void" on wasm32-wasi
On wasm, the age-old C trick of having a main function which can either have no arguments or argc+argv doesn't work, because wasm requires caller and callee signatures to match. WASI's current strategy is to have compilers mangle main's name to indicate which signature they're using. Rust uses the no-argument form, which should be mangled as `__main_void`.
This is needed on wasm32-wasi as of #105395.
This commit adds LLVM Kernel Control Flow Integrity (KCFI) support to
the Rust compiler. It initially provides forward-edge control flow
protection for operating systems kernels for Rust-compiled code only by
aggregating function pointers in groups identified by their return and
parameter types. (See llvm/llvm-project@cff5bef.)
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 #89653).
LLVM KCFI can be enabled with -Zsanitizer=kcfi.
Co-authored-by: bjorn3 <17426603+bjorn3@users.noreply.github.com>
On wasm, the age-old C trick of having a main function which can either have
no arguments or argc+argv doesn't work, because wasm requires caller and
callee signatures to match. WASI's current strategy is to have compilers
mangle main's name to indicate which signature they're using. Rust uses the
no-argument form, which should be mangled as `__main_void`.
This is needed on wasm32-wasi as of #105395.
Stop passing -export-dynamic to wasm-ld.
-export-dynamic was a temporary hack added in the early days of the Rust wasm32 target when Rust didn't have a way to specify wasm exports in the source code. This flag causes all global symbols, and some compiler-internal symbols, to be exported, which is often more than needed.
Rust now does have a way to specify exports in the source code: `#[export_name = "..."]`.
So as the original comment suggests, -export-dynamic can now be removed, allowing users to have smaller binaries and better encapsulation in their wasm32-unknown-unknown modules.
It's possible that this change will require existing wasm32-unknown-unknown users will to add explicit `#[export_name = "..."]` directives to exporrt the symbols that their programs depend on having exported.
-export-dynamic was a temporary hack added in the early days of the Rust
wasm32 target when Rust didn't have a way to specify wasm exports in the
source code. This flag causes all global symbols, and some compiler-internal
symbols, to be exported, which is often more than needed.
Rust now does have a way to specify exports in the source code:
`#[export_name = "..."]`.
So as the original comment suggests, -export-dynamic can now be removed,
allowing users to have smaller binaries and better encapsulation in
their wasm32-unknown-unknown modules.
It's possible that this change will require existing wasm32-unknown-unknown
users will to add explicit `#[export_name = "..."]` directives to
exporrt the symbols that their programs depend on having exported.
Fix passing MACOSX_DEPLOYMENT_TARGET to the linker
I messed up in https://github.com/rust-lang/rust/pull/103929 when merging the two base files together and as a result, started ignoring `MACOSX_DEPLOYMENT_TARGET` at the linker level. This ended up being the cause of nighty builds not running on older macOS versions.
My original hope with the previous PR was that CI would have caught something like that but there were only tests checking the compiler target definitions in codegen tests. Because of how badly this sucks to break, I put together a new test via `run-make` that actually confirms the deployment target set makes it to the linker instead of just LLVM.
Closes https://github.com/rust-lang/rust/issues/104570 (for real this time)
Remove useless borrows and derefs
They are nothing more than noise.
<sub>These are not all of them, but my clippy started crashing (stack overflow), so rip :(</sub>
Improve generating Custom entry function
This commit is aimed at making compiler-generated entry functions (Basically just C `main` right now) more generic so other targets can do similar things for custom entry. This was initially implemented as part of https://github.com/rust-lang/rust/pull/100316.
Currently, this moves the entry function name and Call convention to the target spec.
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
[watchos] Dynamic linking is not allowed for watchos targets
Dynamic linking of all apple targets was (re-) enabled in PR #100636. However, dynamic linking is not allowed on WatchOS so this broke the build of standard library for WatchOS.
This change disables dynamic linking for WatchOS non-simulator targets.
Issue error when -C link-self-contained option is used on unsupported platforms
The documentation was also updated to reflect this.
I'm assuming the supported platforms are the same as initially written in [RELEASES.md](https://github.com/rust-lang/rust/blob/master/RELEASES.md#compiler-17).
Fixes#103576
This commit is aimed at making compiler generated entry functions
(Basically just C `main` right now) more generic so other targets can do
similar things for custom entry. This was initially implemented as part
of https://github.com/rust-lang/rust/pull/100316.
Currently, this moves the entry function name and Call convention to the
target spec.
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
Cleanup Apple-related code in rustc_target
While working on https://github.com/rust-lang/rust/pull/103455, the consistency of the `rustc_target` code for Apple's platforms was "kind of bad." There were two "base" files (`apple_base.rs` and `apple_sdk_base.rs`) that the targets each pulled some parts out of, each and all of them were written slightly differently, and sometimes missed comments other implementations had.
So to hopefully make future maintenance, like implementing https://github.com/rust-lang/compiler-team/issues/556, easier, this makes all of them use similar patterns and the same target base logic everywhere instead of picking bits from both. This also has some other smaller upsides like less stringly-typed functions.
fix debuginfo for windows_gnullvm_base.rs
These lines (including the FIXME comment) were added to windows_gnu_base.rs in cf2c492ef8 but windows_gnullvm_base.rs was not updated. This resulted in an error `LLVM ERROR: dwo only supported with ELF and Wasm` attempting to build on aarch64-pc-windows-gnullvm.
See also https://github.com/msys2/MINGW-packages/pull/13921#issuecomment-1304391707
/cc ```@mati865``` ```@davidtwco```
r? ```@davidtwco```
These lines (including the FIXME comment) were added to windows_gnu_base.rs in cf2c492ef8 but windows_gnullvm_base.rs was not updated. This resulted in an error `LLVM ERROR: dwo only supported with ELF and Wasm` attempting to build on aarch64-pc-windows-gnullvm.
Signed-off-by: Jeremy Drake <github@jdrake.com>
Fixed consistency of Apple simulator target's ABI
Currently there's a few Apple device simulator targets that are inconsistent since some set `target_abi = "sim"` (the correct thing to do) while a bunch of others don't set anything (`""`). Due to this its very hard to reliability check if some Rust code is running inside a simulator. This changes all of them to do the same thing and set `sim` as their `target_abi`.
The new way to identity a simulator during compilation is as simple as `cfg(all(target_vendor="apple", target_abi = "sim"))` or even `cfg(target_abi = "sim")` being less pedantic about it.
The issues with the current form (and inspiration for this) are also summarized in `@thomcc's` [Tweet](https://twitter.com/at_tcsc/status/1576685244702691328).
Add a tier 3 target for the Sony PlayStation 1
This adds a tier 3 target, `mipsel-sony-psx`, for the Sony PlayStation 1. I've tested it pretty thoroughly with [this SDK](https://github.com/ayrtonm/psx-sdk-rs) I wrote for it.
From the [tier 3 target policy](https://doc.rust-lang.org/rustc/target-tier-policy.html#tier-3-target-policy) (I've omitted the subpoints for brevity, but read over everything)
> A 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.)
I'd be the designated developer
> 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.
The target name follows the conventions of the existing PSP target (`mipsel-sony-psp`) and uses `psx` following the convention of the broader [PlayStation homebrew community](https://psx-spx.consoledev.net/).
> 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.
No legal issues with this target.
> 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.
👍
> 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.
The psx supports `core` and `alloc`, but will likely not support `std` anytime soon.
> 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 binaries, or running tests (even if they do not pass), the documentation must explain how to run such binaries or tests for the target, using emulation if possible or dedicated hardware if necessary.
This target has an SDK and a `cargo-psx` tool for formatting binaries as psx executables. Documentation and examples are provided in the [psx-sdk-rs README](https://github.com/ayrtonm/psx-sdk-rs#psx-sdk-rs), the SDK and cargo tool are both available through crates.io and docs.rs has [SDK documentation](https://docs.rs/psx/latest/psx/).
> 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.
👍
> 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.
No problem
This patch makes it possible to use varargs for calling conventions,
which are either based on C (like efiapi) or C is based
on them (for example sysv64 and win64).
