Skip `Lazy` for some metadata tables
Some metadata tables encode their entries indirectly, through the Lazy construct. This is useful when dealing with variable length encoding, but incurs the extra cost of one u32.
Meanwhile, some fields can be encoded in a single u8, or can use a short fixed-length encoding. This PR proposes to do so, and avoid the overhead.
`impl const Default for Box<[T]>` and `Box<str>`
The unstable `const_default_impls` (#87864) already include empty `Vec<T>` and `String`. Now we extend that concept to `Box<[T]>` and `Box<str>` as well.
This obviates a hack in `rustc_ast`'s `P::<[T]>::new`.
feat: Allow usage of sudo [while not accessing root] in x.py
# Fixes
This PR should fix#93344
# Info
Allows usage of sudo (while not accessing root) in x.py
Rollup of 7 pull requests
Successful merges:
- #95320 (Document the current MIR semantics that are clear from existing code)
- #95722 (pre-push.sh: Use python3 if python is not found)
- #95881 (Use `to_string` instead of `format!`)
- #95909 (rustdoc: Reduce allocations in a `theme` function)
- #95910 (Fix crate_type attribute to not warn on duplicates)
- #95920 (use `Span::find_ancestor_inside` to get right span in CastCheck)
- #95936 (Fix a bad error message for `relative paths are not supported in visibilities` error)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Instead of checking only the user provided sysroot or the default (when
no sysroot is provided), search user provided sysroot and then check
default sysroots for locale requested by the user.
Signed-off-by: David Wood <david.wood@huawei.com>
use `Span::find_ancestor_inside` to get right span in CastCheck
This is a quick fix. This bad suggestion likely lives in other places... but thought it would be useful to fix all of the CastCheck ones first.
Let me know if reviewer would prefer I add more tests for each of the diagnostics in CastCheck, or would like to do a more thorough review of other suggestions that use spans in typeck. I would also be open to further suggestions on how to better expose an API that gives us the "best" span for a diagnostic suggestion.
Fixed#95919
Fix crate_type attribute to not warn on duplicates
In #88681 I accidentally marked the `crate_type` attribute as only allowing a single attribute. However, multiple attributes are allowed (they are joined together [here](027a232755/compiler/rustc_interface/src/util.rs (L530-L542))). This fixes it to not report a warning if duplicates are found.
Closes#95902
rustdoc: Reduce allocations in a `theme` function
`str::replace` allocates a new `String`...
This could probably be made more efficient, but I think it'd have to be clunky imperative code to achieve that.
pre-push.sh: Use python3 if python is not found
Since Python 2 has reached EOL, `python` may not be available in certain systems (e.g., recent macOS). We should use `python3` in this case to avoid error like `python: No such file or directory`.
Document the current MIR semantics that are clear from existing code
This PR adds documentation to places, operands, rvalues, statementkinds, and terminatorkinds that describes their existing semantics and requirements. In many places the semantics depend on the Rust memory model or other T-Lang decisions - when this is the case, it is just noted as such with links to UCG issues where possible. I'm hopeful that none of the documentation added here can be used to justify optimizations that depend on the memory model. The documentation for places and operands probably comes closest to running afoul of this - if people think that it cannot be merged as is, it can definitely also be taken out.
The goal here is to only document parts of MIR that seem to be decided already, or are at least depended on by existing code. That leaves quite a number of open questions - those are marked as "needs clarification." I'm not sure what to do with those in this PR - we obviously can't decide all these questions here. Should I just leave them in as is? Take them out? Keep them in but as `//` instead of `///` comments?
If this is too big to review at once, I can split this up.
r? rust-lang/mir-opt
Faster parsing for lower numbers for radix up to 16 (cont.)
( Continuation of https://github.com/rust-lang/rust/pull/83371 )
With LingMan's change I think this is potentially ready.
Respect -Z verify-llvm-ir and other flags that add extra passes when combined with -C no-prepopulate-passes in the new LLVM Pass Manager.
As part of the switch to the new LLVM Pass Manager the behaviour of flags such as `-Z verify-llvm-ir` (e.g. sanitizer, instrumentation) was modified when combined with `-C no-prepopulate-passes`. With the old PM, rustc was the one manually constructing the pipeline and respected those flags but in the new pass manager, those flags are used to build a list of callbacks that get invoked at certain extension points in the pipeline. Unfortunately, `-C no-prepopulate-passes` would skip building the pipeline altogether meaning we'd never add the corresponding passes. The fix here is to just manually invoke those callbacks as needed.
Fixes#95874
Demonstrating the current vs fixed behaviour using the bug in #95864
```console
$ rustc +nightly asm-miscompile.rs --edition 2021 --emit=llvm-ir -C no-prepopulate-passes -Z verify-llvm-ir
$ echo $?
0
$ rustc +stage1 asm-miscompile.rs --edition 2021 --emit=llvm-ir -C no-prepopulate-passes -Z verify-llvm-ir
Basic Block in function '_ZN14asm_miscompile3foo28_$u7b$$u7b$closure$u7d$$u7d$17h360e2f7eee1275c5E' does not have terminator!
label %bb1
LLVM ERROR: Broken module found, compilation aborted!
```
Rollup of 7 pull requests
Successful merges:
- #95008 ([`let_chains`] Forbid `let` inside parentheses)
- #95801 (Replace RwLock by a futex based one on Linux)
- #95864 (Fix miscompilation of inline assembly with outputs in cases where we emit an invoke instead of call instruction.)
- #95894 (Fix formatting error in pin.rs docs)
- #95895 (Clarify str::from_utf8_unchecked's invariants)
- #95901 (Remove duplicate aliases for `check codegen_{cranelift,gcc}` and fix `build codegen_gcc`)
- #95927 (CI: do not compile libcore twice when performing LLVM PGO)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
