Configure sanitize option when compiling with a sanitizer to make
it possible to execute different code depending on whether given
sanitizer is enabled or not.
Format liballoc with rustfmt
Same strategy as #66691 -- as with my previous formatting PRs, I am avoiding causing merge conflicts in other PRs by only touches those files that are not involved in any currently open PR. Files that appear in new PRs between when this PR is opened and when it makes it to the top of the bors queue will be reverted from this PR.
The list of files involved in open PRs is determined by querying GitHub's GraphQL API [with this script](https://gist.github.com/dtolnay/aa9c34993dc051a4f344d1b10e4487e8).
With the list of files from the script in outstanding_files, the relevant commands were:
```
$ find src/liballoc -name '*.rs' \
| xargs rustfmt --edition=2018 --unstable-features --skip-children
$ rg liballoc outstanding_files | xargs git checkout --
```
To confirm no funny business:
```
$ git checkout $THIS_COMMIT^
$ git show --pretty= --name-only $THIS_COMMIT \
| xargs rustfmt --edition=2018 --unstable-features --skip-children
$ git diff $THIS_COMMIT # there should be no difference
```
r? @Dylan-DPC
Use recursion_limit for const eval stack limit
cc https://github.com/rust-lang/miri/issues/643 @orium @RalfJung
I'm really not certain how exactly to handle this change, but it looks like it's that simple.
Reuse `recursion_limit` ("The maximum recursion limit for potentially infinitely recursive operations such as auto-dereference and monomorphization") which is configurable by the user for the const evaluation stack frame limit.
The other option is to make `const_eval_stack_frame_limit` configurable in the same way as `recursion_limit` (but I'm not sure how to do that and it'd be a bigger change).
Fixes https://github.com/rust-lang/miri/issues/643.
Improve lifetime errors with implicit trait object lifetimes
r? @matthewjasper
cc @estebank
I still think the ideal solution would be to construct a `BrAnon`, but that seems like a more invasive change, and can be done later. This at least gets rid of the hack in `OutliveSuggestion` and is slightly more principled.
Miri: run panic-catching tests in liballoc
I also converted two tests from using `thread::spawn(...).join()` just for catching panics, to `catch_panic`, so that Miri can run them.
More useful test error messages on should_panic(expected=...) mismatch
Fixes #66304
r? @gilescope
Shows both the actual as well as the expected panic value when a test with `should_panic(expected=...)` fails.
This makes `should_panic` more consistent with `assert_eq`.
I am not sure whether printing the `Any::type_id()` is useful, is there something better that we could print for non-string panic values?
Feature gating *declarations* => new crate `rustc_feature`
This PR moves the data-oriented parts of feature gating into its own crate, `rustc_feature`.
The parts consist of some data types as well as `accepted`, `active`, `removed`, and `builtin_attrs`.
Feature gate checking itself remains in `syntax::feature_gate::check`. The parts which define how to emit feature gate errors could probably be moved to `rustc_errors` or to the new `rustc_session` crate introduced in #66878. The visitor itself could probably be moved as a pass in `rustc_passes` depending on how the dependency edges work out.
The PR also contains some drive-by cleanup of feature gate checking. As such, the PR probably best read commit-by-commit.
r? @oli-obk
cc @petrochenkov
cc @Mark-Simulacrum
Remove unneeded prelude imports in libcore tests
These three lines are from c82da7a54b9efb1a0ccbe11de66c71f547bf7db9 dating back to 2015.
They cause problems when applying rustfmt to the codebase, because reordering wildcard imports can trigger new unused import warnings.
As a minimized example, the following program compiles successfully:
```rust
#![deny(unused_imports)]
use std::fmt::Debug;
use std::marker::Send;
pub mod repro {
use std::prelude::v1::*;
use super::*;
pub type D = dyn Debug;
pub type S = dyn Send;
}
pub type S = dyn Send;
```
but putting it through rustfmt produces a program that fails to compile:
```rust
#![deny(unused_imports)]
use std::fmt::Debug;
use std::marker::Send;
pub mod repro {
use super::*;
use std::prelude::v1::*;
pub type D = dyn Debug;
pub type S = dyn Send;
}
pub type S = dyn Send;
```
The error is:
```console
error: unused import: `std::prelude::v1::*`
--> src/main.rs:8:9
|
8 | use std::prelude::v1::*;
| ^^^^^^^^^^^^^^^^^^^
```
Make python-generated source files compatible with rustfmt
This PR adjusts the generators for src/libcore/num/dec2flt/table.rs, src/libcore/unicode/printable.rs, and src/libcore/unicode/tables.rs to make it so running `rustfmt` on the generated files no longer needs to apply any changes.
This involves tweaking the python scripts where reasonable to better match rustfmt's style, and adding `#[rustfmt::skip]` to big constant tables that there's no point having rustfmt rewrap.
r? @Dylan-DPC
rustc_typeck: gate AnonConst's generics on feature(const_generics).
This PR employs the fix for #43408 when `#![feature(const_generics)]` is enabled, making the feature-gate the opt-in for all the possible breakage this may incur.
For example, if this PR lands, this will cause a cycle error (due to #60471):
```rust
#![feature(const_generics)]
fn foo<T: Into<[u8; 4]>>() {}
```
And so will anything with type-level const expressions, in its bounds.
Surprisingly, `impl`s don't seem to be affected (if they were, even libcore wouldn't compile).
One thing I'm worried about is not knowing how much unstable code out there, using const-generics, will be broken. But types like `Foo<{N+1}>` never really worked, and do after this PR, just not in bounds - so ironically, it's type-level const expressions that don't depend on generics, which will break (in bounds).
Also, if we do this, we'll have effectively blocked stabilization of const generics on #60471.
r? @oli-obk cc @varkor @yodaldevoid @nikomatsakis
Use LLVMAddAnalysisPasses instead of Rust's wrapper
LLVM exposes a C API `LLVMAddAnalysisPasses` and hence Rust's own wrapper `LLVMRustAddAnalysisPasses` is not needed anymore.
impl TrustedLen for vec::Drain
The iterator methods just forward to `slice::Iter`, which is `TrustedLen`.
This can probably be applied to other `Drain` structs as well.
Atomic as_mut_ptr
I encountered the following pattern a few times: In Rust we use some atomic type like `AtomicI32`, and an FFI interface exposes this as `*mut i32` (or some similar `libc` type).
It was not obvious to me if a just transmuting a pointer to the atomic was acceptable, or if this should use a cast that goes through an `UnsafeCell`. See https://github.com/rust-lang/rust/issues/66136#issuecomment-557802477
Transmuting the pointer directly:
```rust
let atomic = AtomicI32::new(1);
let ptr = &atomic as *const AtomicI32 as *mut i32;
unsafe {
ffi(ptr);
}
```
A dance with `UnsafeCell`:
```rust
let atomic = AtomicI32::new(1);
unsafe {
let ptr = (&*(&atomic as *const AtomicI32 as *const UnsafeCell<i32>)).get();
ffi(ptr);
}
```
Maybe in the end both ways could be valid. But why not expose a direct method to get a pointer from the standard library?
An `as_mut_ptr` method on atomics can be safe, because only the use of the resulting pointer is where things can get unsafe. I documented its use for FFI, and "Doing non-atomic reads and writes on the resulting integer can be a data race."
The standard library could make use this method in a few places in the WASM module.
cc @RalfJung as you answered my original question.
Initial implementation of or-pattern usefulness checking
The title says it all.
I'd like to request a perf run on that, hopefully this doesn't kill performance too much.
cc https://github.com/rust-lang/rust/issues/54883
These three lines are from c82da7a54b9efb1a0ccbe11de66c71f547bf7db9 in
2015.
They cause problems when applying rustfmt to the codebase, because
reordering wildcard imports can trigger new unused import warnings.
As a minimized example, the following program compiles successfully:
#![deny(unused_imports)]
use std::fmt::Debug;
use std::marker::Send;
pub mod repro {
use std::prelude::v1::*;
use super::*;
pub type D = dyn Debug;
pub type S = dyn Send;
}
pub type S = dyn Send;
but putting it through rustfmt produces a program that fails to compile:
#![deny(unused_imports)]
use std::fmt::Debug;
use std::marker::Send;
pub mod repro {
use super::*;
use std::prelude::v1::*;
pub type D = dyn Debug;
pub type S = dyn Send;
}
pub type S = dyn Send;
The error is:
error: unused import: `std::prelude::v1::*`
--> src/main.rs:8:9
|
8 | use std::prelude::v1::*;
| ^^^^^^^^^^^^^^^^^^^
