Emit allocator attributes for allocator shim
This emits the same attributes we place on allocator declarations on the definitions in the allocator shim as well. This complements https://github.com/rust-lang/rust/pull/146766, which added the attribute for `#[global_allocator]` definitions. Emitting the attributes on the definitions ensures that they cannot be lost of the allocator shim participates in LTO.
See https://github.com/rust-lang/rust/issues/145995 for context, though that one was about `#[global_allocator]`. I'm not sure whether this can occur with the allocator shim as well or not, but better safe than sorry.
I'm not sure whether there is any good way to test this, as the allocator shim is not part of `--emit=llvm-ir`. I've verified this locally by inspecting the bitcode produced by `-C save-temps`.
r? ``@bjorn3``
mbe: macro_check: Fix function comments referencing non-existent parameters
Several functions had comments referencing a non-existent `valid`
parameter. Remove those. The `guar` parameter that handles errors is
already documented.
In the process, remove another duplicate reference to an
already-documented parameter (`binders`).
std: implement `hostname`
Resolves https://github.com/rust-lang/libs-team/issues/330
Tracking issue: https://github.com/rust-lang/rust/issues/135142
This is based on rust-lang/rust#135141, but I've reimplemented the UNIX version, which now:
* uses `sysconf(_SC_HOST_NAME_MAX)` as an initial buffer length
* returns `OutOfMemory` if the `Vec` allocation fails
* retries the operation if it detects that the name returned by `gethostname` was truncated
Additionally, as part of the rebase, I had to move some WinSock abstractions (initialisation and error access) to `sys::pal` so that they can be accessed from `sys::net::hostname`.
CC ``@orowith2os`` (and thank you for your work!)
debuginfo: add an unstable flag to write split DWARF to an explicit directory
Bazel requires knowledge of outputs from actions at analysis time, including file or directory name. In order to work around the lack of predictable output name for dwo files, we group the dwo files in a subdirectory of --out-dir as a post-processing step before returning control to bazel. Unfortunately some debugging workflows rely on directly opening the dwo file rather than loading the merged dwp file, and our trick of moving the files breaks those users. We can't just hardlink the file or copy it, because with remote build execution we wouldn't end up with the un-moved file copied back to the developer's workstation. As a fix, we add this unstable flag that causes dwo files to be written to a build-system-controllable location, which then lets bazel hoover up the dwo files, but the objects also have the correct path for the dwo files.
r? `@davidtwco`
This allows building a rustc capable of running the frontend without any
backend present. While this may not seem all that useful, it allows
running the frontend of rustc to report errors or running miri to
interpret a program without any backend present. This is useful when you
are trying to say run miri in the browser as upstream LLVM can't be
compiled for wasm yet. Or to run rustc itself in miri like I did a while
ago and caught some UB.
Rollup of 5 pull requests
Successful merges:
- rust-lang/rust#146653 (improve diagnostics for empty attributes)
- rust-lang/rust#146987 (impl Ord for params and use unstable sort)
- rust-lang/rust#147101 (Use `Iterator::eq` and (dogfood) `eq_by` in compiler and library )
- rust-lang/rust#147123 (Fix removed version numbers of `doc_auto_cfg` and `doc_cfg_hide`)
- rust-lang/rust#147149 (add joboet to library review rotation)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix removed version numbers of `doc_auto_cfg` and `doc_cfg_hide`
Tracking issue: https://github.com/rust-lang/rust/issues/43781
The `doc_auto_cfg` and `doc_cfg_hide` features were removed in a recent nightly (by https://github.com/rust-lang/rust/pull/138907).
I believe that the rustc version numbers at which the features were declared to be removed were incorrect, however, and should both be "1.92" (±1). As evidence in favour of this, the error we get from using this was:
```text
error[E0557]: feature has been removed
--> src/lib.rs:22:29
|
22 | #![cfg_attr(docsrs, feature(doc_auto_cfg))]
| ^^^^^^^^^^^^ feature has been removed
|
= note: removed in 1.58.0; see <https://github.com/rust-lang/rust/pull/138907> for more information
= note: merged into `doc_cfg`
```
Note especially the "removed in 1.58" claim. Further evidence is found in the comment further up this file: 4ffeda10e1/compiler/rustc_feature/src/removed.rs (L49-L53)
I've chosen 1.92 as that was the milestone which https://github.com/rust-lang/rust/pull/138907 was added to.
cc `@GuillaumeGomez`
Use `Iterator::eq` and (dogfood) `eq_by` in compiler and library
Now that rust-lang/rust#137122 has landed, we can replace stuff that looks like:
```rust
let a: &[T];
let b: &[T];
let eq = a.len() == b.len() && a.iter().zip(b).all(|(a,b)| a == b)
```
with the much simpler `a.iter().eq(b)`, without losing the perf benefit of the different-length-fast-path.
Also dogfooded `Iterator::eq_by` (cc rust-lang/rust#64295 ) while I'm at it.
First commit (4d1b6fad230f8a5ccceccc7562eadc4ea50059da) should be very straightforward to review, second one (049a4606cb3906787aedf508ee8eea09c2bb3b9a) is slightly more creative, but IMHO a nice cleanup.
impl Ord for params and use unstable sort
AFAICT we are only sorting to find duplicates, so unstable sort should work fine, and maybe is a tiny bit faster?
improve diagnostics for empty attributes
Adds a note about them not having any effect. This was previously done for `feature` attributes but no other attributes. In [converting the `feature` parser](https://github.com/rust-lang/rust/pull/146652) I removed that note. This PR adds it back in and makes it so all attributes benefit from it.
Not blocked on rust-lang/rust#146652, either can merge first
This emits the same attributes we place on allocator declarations
(and allocator definitions using `#[global_allocator]`) on the
definitions in the allocator shim as well, making sure that the
attributes are not lost if the allocator shim participates in LTO.
remove explicit deref of AbiAlign for most methods
Much of the compiler calls functions on Align projected from AbiAlign. AbiAlign impls Deref to its inner Align, so we can simplify these away. Also, it will minimize disruption when AbiAlign is removed.
For now, preserve usages that might resolve to PartialOrd or PartialEq, as those have odd inference.
compiler: remove AbiAlign inside TargetDataLayout
AbiAlign is a thin wrapper around Align, extant mostly because we used to track a separate quasi-notion of alignment that was never a real notion of alignment and removing all of it at once was too churny. This PR maintains AbiAlign usage in public API and most of the compiler, but direct access of these fields for TargetDataLayout is now in terms of Align only.
tests: Remove ignore-android directive for fixed issue
rust-lang/rust#120567 is marked as fixed, so let's see if we can remove the ignore directives tied to that issue.
<!-- Note to self: wait for https://github.com/rust-lang/team/pull/2002 -->
try-job: arm-android
Rollup of 7 pull requests
Successful merges:
- rust-lang/rust#133477 (Detect tuple structs that are unconstructable due to re-export)
- rust-lang/rust#146929 (compiletest: Remove old-output-capture and become a stage0 bootstrap tool)
- rust-lang/rust#146979 (constify Default on Nanoseconds)
- rust-lang/rust#147092 (Do not compute optimized MIR if code does not type-check.)
- rust-lang/rust#147112 (all 48 keywords in just 300 characters)
- rust-lang/rust#147122 (Fix some crash-test directives)
- rust-lang/rust#147127 (Add a leading dash to linker plugin arguments in the gcc codegen)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix some crash-test directives
- 120175 fails to crash for non-ELF targets; presumably this wasn't noticed because the CI jobs don't enable rustc assertions for non-ELF hosts.
- 34127, 125722, and 131292 have `only-x86_64`, which is overly specific.
- Unnecessary x86 directives cause friction for contributors using aarch64, especially now that many PR CI jobs also use aarch64.
r? ghost
compiletest: Remove old-output-capture and become a stage0 bootstrap tool
The new compiletest output-capture system became the default in rust-lang/rust#146574, and no problems have been reported since.
This PR therefore removes the old output-capture implementation from compiletest, and adjusts bootstrap to always build and test compiletest as a stage0 bootstrap tool.
In other words, compiletest no longer relies on any unstable features (such as `libtest` or `internal_output_capture`), and is now written entirely in stable Rust!
The compiletest self-tests still need access to an in-tree rustc, in order to obtain information via `rustc --print`, so we interpret `--stage` as indicating the stage of that secondary compiler, but always use the stage0 compiler to build compiletest itself.
r? Kobzol
Detect tuple structs that are unconstructable due to re-export
When a tuple-struct is re-exported that has inaccessible fields at the `use` scope, the type's constructor cannot be accessed through that re-export. We now account for this case and extend the resulting resolution error. We also check if the constructor would be accessible directly, not through the re-export, and if so, we suggest using the full path instead.
```
error[E0423]: cannot initialize a tuple struct which contains private fields
--> $DIR/ctor-not-accessible-due-to-inaccessible-field-in-reexport.rs:12:33
|
LL | let crate::Foo(x) = crate::Foo(42);
| ^^^^^^^^^^
|
note: the type is accessed through this re-export, but the type's constructor is not visible in this import's scope due to private fields
--> $DIR/ctor-not-accessible-due-to-inaccessible-field-in-reexport.rs:3:9
|
LL | pub use my_mod::Foo;
| ^^^^^^^^^^^
help: the type can be constructed directly, because its fields are available from the current scope
|
LL | let crate::Foo(x) = crate::my_mod::Foo(42);
| ~~~~~~~~~~~~~~~~~~
```
Fix#133343.
Skip stack overflow handler for panic=immediate-abort
std installs guard pages and a signal handler to ensure that stackoverflows 1) terminate abruptly and 2) print an nice message. Even for panic=immediate-abort, 1) is desirable, we don't want silent data corruption there. But 2) is completely unnecessary, as users deliberately *don't* want nice messages, they want minimum binary size.
Therefore, skip the entire guard signal handler setup, which saves a lot of bytes.
I tested this with a hello world binary using fat LTO, build-std, panic=immediate-abort, opt-level=s, strip=debuginfo.
`size` reports significant savings:
```
text data bss dec hex filename
15252 1032 104 16388 4004 tiny-before
6881 964 48 7893 1ed5 tiny-after2
```
`nm -U` goes from 71 to 56, getting rid of a bunch of stack overflow related symbols. The disk size goes from `31k` to `24k`.
The impact on the error message is minimal, as the message was already
missing.
before:
```
fish: Job 1, './tiny-so-before' terminated by signal SIGABRT (Abort)
```
after:
```
fish: Job 1, './tiny-so-after' terminated by signal SIGSEGV (Address boundary error)
```
I didn't test the Windows part, but it likely also has savings.
Much of the compiler calls functions on Align projected from AbiAlign.
AbiAlign impls Deref to its inner Align, so we can simplify these away.
Also, it will minimize disruption when AbiAlign is removed.
For now, preserve usages that might resolve to PartialOrd or PartialEq,
as those have odd inference.
When a tuple-struct is re-exported that has inaccessible fields at the `use` scope, the type's constructor cannot be accessed through that re-export. We now account for this case and extend the resulting resolution error. We also check if the constructor would be accessible directly, not through the re-export, and if so, we suggest using the full path instead.
```
error[E0423]: cannot initialize a tuple struct which contains private fields
--> $DIR/ctor-not-accessible-due-to-inaccessible-field-in-reexport.rs:12:33
|
LL | let crate::Foo(x) = crate::Foo(42);
| ^^^^^^^^^^
|
note: the type is accessed through this re-export, but the type's constructor is not visible in this import's scope due to private fields
--> $DIR/ctor-not-accessible-due-to-inaccessible-field-in-reexport.rs:3:9
|
LL | pub use my_mod::Foo;
| ^^^^^^^^^^^
help: the type can be constructed directly, because its fields are available from the current scope
|
LL | let crate::Foo(x) = crate::my_mod::Foo(42);
| ~~~~~~~~~~~~~~~~~~
```
Fix#133343.
```
error[E0716]: temporary value dropped while borrowed
--> $DIR/multiple-sources-for-outlives-requirement.rs:5:38
|
LL | fn foo<'b>() {
| -- lifetime `'b` defined here
LL | outlives_indir::<'_, 'b, _>(&mut 1u32);
| ---------------------------------^^^^-- temporary value is freed at the end of this statement
| | |
| | creates a temporary value which is freed while still in use
| argument requires that borrow lasts for `'b`
|
note: requirements that the value outlives `'b` introduced here
--> $DIR/multiple-sources-for-outlives-requirement.rs:1:23
|
LL | fn outlives_indir<'a: 'b, 'b, T: 'a>(_x: T) {}
| ^^ ^^
```
