It looks like LLD will detect object files being either 32 or 64-bit
depending on any memory present. LLD will additionally reject 32-bit
objects during a 64-bit link. Previously metadata objects did not have
any memories in them which led LLD to conclude they were 32-bit objects
which broke 64-bit targets for wasm.
This commit fixes this by ensuring that for 64-bit targets there's a
memory object present to get LLD to detect it's a 64-bit target.
Additionally this commit moves away from a hand-crafted wasm encoder to
the `wasm-encoder` crate on crates.io as the complexity grows for the
generated object file.
Closes#121460
Unify dylib loading between proc macros and codegen backends
As bonus this makes the errors when failing to load a proc macro more informative to match the backend loading errors. In addition it makes it slightly easier to patch rustc to work on platforms that don't support dynamic linking like wasm.
As bonus this makes the errors when failing to load a proc macro more
informative to match the backend loading errors. In addition it makes it
slightly easier to patch rustc to work on platforms that don't support
dynamic linking like wasm.
The goal of this commit is to remove warnings using LLVM tip-of-tree
`wasm-ld`. In llvm/llvm-project#78658 the `wasm-ld` LLD driver no longer
looks at archive indices and instead looks at all the objects in
archives. Previously `lib.rmeta` files were simply raw rustc metadata
bytes, not wasm objects, meaning that `wasm-ld` would emit a warning
indicating so.
WebAssembly targets previously passed `--fatal-warnings` to `wasm-ld` by
default which meant that if Rust were to update to LLVM 18 then all wasm
targets would not work. This immediate blocker was resolved in
rust-lang/rust#120278 which removed `--fatal-warnings` which enabled a
theoretical update to LLVM 18 for wasm targets. This current state is
ok-enough for now because rustc squashes all linker output by default if
it doesn't fail. This means, for example, that rustc squashes all the
linker warnings coming out of `wasm-ld` about `lib.rmeta` files with
LLVM 18. This again isn't a pressing issue because the information is
all hidden, but it runs the risk of being annoying if another linker
error were to happen and then the output would have all these unrelated
warnings that couldn't be fixed.
Thus, this PR comes into the picture. The goal of this PR is to resolve
these warnings by using the WebAssembly object file format on wasm
targets instead of using raw rustc metadata. When I first implemented
the rlib-in-objects scheme in #84449 I remember either concluding that
`wasm-ld` would either include the metadata in the output or I thought
we didn't have to do anything there at all. I think I was wrong on both
counts as `wasm-ld` does not include the metadata in the final output
unless the object is referenced and we do actually need to do something
to resolve these warnings.
This PR updates the object file format containing rustc metadata on
WebAssembly targets to be an actual WebAssembly file. This enables the
`wasm` feature of the `object` crate to be able to read the custom
section in the same manner as other platforms, but currently `object`
doesn't support writing wasm object files so a handwritten encoder is
used instead.
The only caveat I know of with this is that if `wasm-ld` does indeed
look at the object file then the metadata will be included in the final
output. I believe the only thing that could cause that at this time is
`--whole-archive` which I don't think is passed for rlibs. I would
clarify that I'm not 100% certain about this, however.
tidy: reduce allocs
this reduces allocs in tidy from (dhat output)
```
==31349== Total: 1,365,199,543 bytes in 4,774,213 blocks
==31349== At t-gmax: 10,975,708 bytes in 66,093 blocks
==31349== At t-end: 2,880,947 bytes in 12,332 blocks
==31349== Reads: 5,210,008,956 bytes
==31349== Writes: 1,280,920,127 bytes
```
to
```
==66633== Total: 791,565,538 bytes in 3,503,144 blocks
==66633== At t-gmax: 10,914,511 bytes in 65,997 blocks
==66633== At t-end: 395,531 bytes in 941 blocks
==66633== Reads: 4,249,388,949 bytes
==66633== Writes: 814,119,580 bytes
```
<del>by wrapping regex and updating `ignore` (effect probably not only from `ignore`, didn't measured)</del>
also moves one more regex into `Lazy` to reduce regex rebuilds.
yes, once_cell better, but ...
this reduces from
==31349== Total: 1,365,199,543 bytes in 4,774,213 blocks
==31349== At t-gmax: 10,975,708 bytes in 66,093 blocks
==31349== At t-end: 2,880,947 bytes in 12,332 blocks
==31349== Reads: 5,210,008,956 bytes
==31349== Writes: 1,280,920,127 bytes
to
==47796== Total: 821,467,407 bytes in 3,955,595 blocks
==47796== At t-gmax: 10,976,209 bytes in 66,100 blocks
==47796== At t-end: 2,944,016 bytes in 12,490 blocks
==47796== Reads: 4,788,959,023 bytes
==47796== Writes: 975,493,639 bytes
miropt-test-tools: remove regex usage
this removes regex usage and slightly refactors ext stripping in one case
Update mdbook to 0.4.37
This updates mdbook to 0.4.37.
Changelog: https://github.com/rust-lang/mdBook/blob/master/CHANGELOG.md#mdbook-0437
The primary change is the update to pulldown-cmark which has a large number of markdown parsing changes. There shouldn't be any significant changes to the rendering of any of the books (I have posted some PRs to fix some minor issues to the ones that were affected).
The existing regex-based HTML parsing was just too primitive to
correctly handle HTML content. Some books have legitimate `href="…"`
text which should not be validated because it is part of the text, not
actual HTML.
Actually abort in -Zpanic-abort-tests
When a test fails in panic=abort, it can be useful to have a debugger or other tooling hook into the `abort()` call for debugging. Doing this some other way would require it to hard code details of Rust's panic machinery.
There's no reason we couldn't have done this in the first place; using a single exit code for "success" or "failed" was just simpler. Now we are aware of the special exit codes for posix and windows platforms, logging a special error if an unrecognized code is used on those platforms, and falling back to just "failure" on other platforms.
This continues to account for `#[should_panic]` inside the test process itself, so there's no risk of misinterpreting a random call to `abort()` as an expected panic. Any exit code besides `TR_OK` is logged as a test failure.
As an added benefit, this would allow us to support panic=immediate_abort (but not `#[should_panic]`), without noise about unexpected exit codes when a test fails.
Fixes footnote handling in rustdoc
Fixes#100638.
You can now declare footnotes like this:
```rust
//! Reference to footnotes A[^1], B[^2] and C[^3].
//!
//! [^1]: Footnote A.
//! [^2]: Footnote B.
//! [^3]: Footnote C.
```
r? `@notriddle`
Error codes are integers, but `String` is used everywhere to represent
them. Gross!
This commit introduces `ErrCode`, an integral newtype for error codes,
replacing `String`. It also introduces a constant for every error code,
e.g. `E0123`, and removes the `error_code!` macro. The constants are
imported wherever used with `use rustc_errors::codes::*`.
With the old code, we have three different ways to specify an error code
at a use point:
```
error_code!(E0123) // macro call
struct_span_code_err!(dcx, span, E0123, "msg"); // bare ident arg to macro call
\#[diag(name, code = "E0123")] // string
struct Diag;
```
With the new code, they all use the `E0123` constant.
```
E0123 // constant
struct_span_code_err!(dcx, span, E0123, "msg"); // constant
\#[diag(name, code = E0123)] // constant
struct Diag;
```
The commit also changes the structure of the error code definitions:
- `rustc_error_codes` now just defines a higher-order macro listing the
used error codes and nothing else.
- Because that's now the only thing in the `rustc_error_codes` crate, I
moved it into the `lib.rs` file and removed the `error_codes.rs` file.
- `rustc_errors` uses that macro to define everything, e.g. the error
code constants and the `DIAGNOSTIC_TABLES`. This is in its new
`codes.rs` file.
Avoid code generation for ThinVec<Diagnostic>'s destructor in the query system
This avoids 2 instances of the destructor of `ThinVec<Diagnostic>` from being included in `execute_job`. It also outlines the cold branch in `store_side_effects` / `store_side_effects_for_anon_node`.
pat_analysis: Don't rely on contiguous `VariantId`s outside of rustc
Today's pattern_analysis uses `BitSet` and `IndexVec` on the provided enum variant ids, which only makes sense if these ids count the variants from 0. In rust-analyzer, the variant ids are global interning ids, which would make `BitSet` and `IndexVec` ridiculously wasteful. In this PR I add some shims to use `FxHashSet`/`FxHashMap` instead outside of rustc.
r? ```@compiler-errors```
Use `zip_eq` to enforce that things being zipped have equal sizes
Some `zip`s are best enforced to be equal, since size mismatches suggest deeper bugs in the compiler.
Exhaustiveness: remove the need for arena-allocation within the algorithm
After https://github.com/rust-lang/rust/pull/119688, exhaustiveness checking doesn't need access to the arena anymore. This simplifies the lifetime story and makes it compile on stable without the extra dependency.
r? `@compiler-errors`
next solver: provisional cache
this adds the cache removed in #115843. However, it should now correctly track whether a provisional result depends on an inductive or coinductive stack.
While working on this, I was using the following doc: https://hackmd.io/VsQPjW3wSTGUSlmgwrDKOA. I don't think it's too helpful to understanding this, but am somewhat hopeful that the inline comments are more useful.
There are quite a few future perf improvements here. Given that this is already very involved I don't believe it is worth it (for now). While working on this PR one of my few attempts to significantly improve perf ended up being unsound again because I was not careful enough ✨
r? `@compiler-errors`
annotate-snippets: update to 0.10
Ports `annotate-snippets` to 0.10, temporary dupes versions; other crates left that depends on 0.9 is `ui_test` and `rustfmt`.
The standard library's std::sync::mpsc basically is a crossbeam channel,
and for the use case here will definitely suffice. This drops this
dependency from librustc_driver.
This involves lots of breaking changes. There are two big changes that
force changes. The first is that the bitflag types now don't
automatically implement normal derive traits, so we need to derive them
manually.
Additionally, bitflags now have a hidden inner type by default, which
breaks our custom derives. The bitflags docs recommend using the impl
form in these cases, which I did.
Make exhaustiveness usable outside of rustc
With this PR, `rustc_pattern_analysis` compiles on stable (with the `stable` feature)! `rust-analyzer` will be able to use it to provide match-related diagnostics and refactors.
Two questions:
- Should I name the feature `nightly` instead of `rustc` for consistency with other crates? `rustc` makes more sense imo.
- `typed-arena` is an optional dependency but tidy made me add it to the allow-list anyway. Can I avoid that somehow?
r? `@compiler-errors`
Add instance evaluation and methods to read an allocation in StableMIR
The instance evaluation is needed to handle intrinsics such as `type_id` and `type_name`.
Since we now use Allocation to represent all evaluated constants, provide a few methods to help process the data inside an allocation.
I've also started to add a structured way to get information about the compilation target machine. For now, I've only added information needed to process an allocation.
r? ``````@ouz-a``````
The instance evaluation is needed to handle intrinsics such as
`type_id` and `type_name`.
Since we now use Allocation to represent all evaluated constants,
provide a few methods to help process the data inside an allocation.
Use `unwinding` crate for unwinding on Xous platform
This patch adds support for using [unwinding](https://github.com/nbdd0121/unwinding) on platforms where libunwinding isn't viable. An example of such a platform is `riscv32imac-unknown-xous-elf`.
### Background
The Rust project maintains a fork of llvm at [llvm-project](https://github.com/rust-lang/llvm-project/) where it applies patches on top of the llvm project. This mostly seems to be to get unwinding support for the SGX project, and there may be other patches that I'm unaware of.
There is a lot of machinery in the build system to support compiling `libunwind` on other platforms, and I needed to add additional patches to llvm in order to add support for Xous.
Rather than continuing down this path, it seemed much easier to use a Rust-based library. The `unwinding` crate by `@nbdd0121` fits this description perfectly.
### Future work
This could potentially replace the custom patches for `libunwind` on other platforms such as SGX, and could enable unwinding support on many more exotic platforms.
### Anti-goals
This is not designed to replace `libunwind` on tier-one platforms or those where unwinding support already exists. There is already a well-established approach for unwinding there. Instead, this aims to enable unwinding on new platforms where C++ code may be difficult to compile.
Report errors in jobserver inherited through environment variables
This pr attempts to catch situations, when jobserver exists, but is not being inherited.
r? `@petrochenkov`
