Commit Graph

148430 Commits

Author SHA1 Message Date
Jonas Schievink bd16825767 Allow `async {}` expressions in const contexts 2021-05-16 02:06:40 +02:00
bors 8cf990c9b5 Auto merge of #84920 - Aaron1011:pretty-print-rental, r=petrochenkov
Remove some unncessary spaces from pretty-printed tokenstream output

In addition to making the output look nicer for all crates, this also
aligns the pretty-printing output with what the `rental` crate expects.
This will allow us to eventually disable a backwards-compat hack in a
follow-up PR.

See https://github.com/rust-lang/rust/issues/84428 for some background information about why we want to make this change. Note that this change would be desirable (but not particularly necessary) even if `rental` didn't exist, so we're not adding any crate-specific hacks into the compiler.
2021-05-15 19:58:59 +00:00
bors 50f2bf6a57 Auto merge of #85335 - GuillaumeGomez:rollup-0tvc14g, r=GuillaumeGomez
Rollup of 4 pull requests

Successful merges:

 - #84751 (str::is_char_boundary - slight optimization)
 - #85185 (Generate not more docs than necessary)
 - #85324 (Warn about unused `pub` fields in non-`pub` structs)
 - #85329 (fix version_str comment)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2021-05-15 17:37:18 +00:00
Aaron Hill 357c013ff5
Remove some unncessary spaces from pretty-printed tokenstream output
In addition to making the output look nicer for all crates, this also
aligns the pretty-printing output with what the `rental` crate expects.
This will allow us to eventually disable a backwards-compat hack in a
follow-up PR.
2021-05-15 12:05:03 -04:00
Guillaume Gomez 8ea8252ca5
Rollup merge of #85329 - RalfJung:version, r=Mark-Simulacrum
fix version_str comment

This version string is ultimately generated here
87423fbc6a/src/bootstrap/channel.rs (L72)
and I don't think it includes the `rustc` prefix. That also matches its use here
ac923d94f8/compiler/rustc_driver/src/lib.rs (L758)
2021-05-15 17:56:50 +02:00
Guillaume Gomez 7a6a25eb2e
Rollup merge of #85324 - FabianWolff:issue-85255, r=varkor
Warn about unused `pub` fields in non-`pub` structs

This pull request fixes #85255. The current implementation of dead code analysis is too prudent because it marks all `pub` fields of structs as live, even though they cannot be accessed from outside of the current crate if the struct itself only has restricted or private visibility.

I have changed this behavior to take the containing struct's visibility into account when looking at field visibility and liveness. This also makes dead code warnings more consistent; consider the example given in #85255:
```rust
struct Foo {
    a: i32,
    pub b: i32,
}

struct Bar;

impl Bar {
    fn a(&self) -> i32 { 5 }
    pub fn b(&self) -> i32 { 6 }
}

fn main() {
    let _ = Foo { a: 1, b: 2 };
    let _ = Bar;
}
```
Current nightly already warns about `Bar::b()`, even though it is `pub` (but `Bar` is not). It should therefore also warn about `Foo::b`, which it does with the changes in this PR.
2021-05-15 17:56:49 +02:00
Guillaume Gomez f851f97e87
Rollup merge of #85185 - GuillaumeGomez:generate-not-more-docs-than-necessary, r=Mark-Simulacrum
Generate not more docs than necessary

This is something that `@Nemo157` was talking about: they wanted that when using `x.py doc std`, it only generated `std` (and the crates "before" it).

r? `@Mark-Simulacrum`
2021-05-15 17:56:48 +02:00
Guillaume Gomez 62b834fb9f
Rollup merge of #84751 - Soveu:is_char_boundary_opt, r=Amanieu
str::is_char_boundary - slight optimization

Current `str::is_char_boundary` implementation emits slightly more instructions, because it includes an additional branch for `index == s.len()`
```rust
pub fn is_char_boundary(s: &str, index: usize) -> bool {
    if index == 0 || index == s.len() {
        return true;
    }
    match s.as_bytes().get(index) {
        None => false,
        Some(&b) => (b as i8) >= -0x40,
    }
}
```
Just changing the place of `index == s.len()` merges it with `index < s.len()` from `s.as_bytes().get(index)`
```rust
pub fn is_char_boundary2(s: &str, index: usize) -> bool {
    if index == 0 {
        return true;
    }

    match s.as_bytes().get(index) {
        // For some reason, LLVM likes this comparison here more
        None => index == s.len(),
        // This is bit magic equivalent to: b < 128 || b >= 192
        Some(&b) => (b as i8) >= -0x40,
    }
}
```
This one has better codegen on every platform, except powerpc
<details><summary>x86 codegen</summary>
<p>

```nasm
example::is_char_boundary:
        mov     al, 1
        test    rdx, rdx
        je      .LBB0_5
        cmp     rsi, rdx
        je      .LBB0_5
        cmp     rsi, rdx
        jbe     .LBB0_3
        cmp     byte ptr [rdi + rdx], -65
        setg    al
.LBB0_5:
        ret
.LBB0_3:
        xor     eax, eax
        ret

example::is_char_boundary2:
        test    rdx, rdx
        je      .LBB1_1
        cmp     rsi, rdx
        jbe     .LBB1_4
        cmp     byte ptr [rdi + rdx], -65
        setg    al
        ret
.LBB1_1:  ; technically this branch is the same as LBB1_4
        mov     al, 1
        ret
.LBB1_4:
        sete    al
        ret
 ```
</p>
</details>

<details><summary>aarch64 codegen</summary>
<p>

```as
example::is_char_boundary:
        mov     x8, x0
        mov     w0, #1
        cbz     x2, .LBB0_4
        cmp     x1, x2
        b.eq    .LBB0_4
        b.ls    .LBB0_5
        ldrsb   w8, [x8, x2]
        cmn     w8, #65
        cset    w0, gt
.LBB0_4:
        ret
.LBB0_5:
        mov     w0, wzr
        ret

example::is_char_boundary2:
        cbz     x2, .LBB1_3
        cmp     x1, x2
        b.ls    .LBB1_4
        ldrsb   w8, [x0, x2]
        cmn     w8, #65
        cset    w0, gt
        ret
.LBB1_3:
        mov     w0, #1
        ret
.LBB1_4:
        cset    w0, eq
        ret
```

</p>
</details>

<details><summary>riscv64gc codegen</summary>
<p>

example::is_char_boundary:
        seqz    a3, a2
        xor     a4, a1, a2
        seqz    a4, a4
        or      a4, a4, a3
        addi    a3, zero, 1
        bnez    a4, .LBB0_3
        bgeu    a2, a1, .LBB0_4
        add     a0, a0, a2
        lb      a0, 0(a0)
        addi    a1, zero, -65
        slt     a3, a1, a0
.LBB0_3:
        mv      a0, a3
        ret
.LBB0_4:
        mv      a0, zero
        ret

example::is_char_boundary2:
        beqz    a2, .LBB1_3
        bgeu    a2, a1, .LBB1_4
        add     a0, a0, a2
        lb      a0, 0(a0)
        addi    a1, zero, -65
        slt     a0, a1, a0
        ret
.LBB1_3:
        addi    a0, zero, 1
        ret
.LBB1_4:
        xor     a0, a1, a2
        seqz    a0, a0
        ret

</p>
</details>

[Link to godbolt](https://godbolt.org/z/K8avEz8Gr)

`@rustbot` label: A-codegen
2021-05-15 17:56:47 +02:00
Guillaume Gomez b9b67b7d5b Don't generate more docs than necessary 2021-05-15 17:21:12 +02:00
bors eac3c7c5bd Auto merge of #82208 - jyn514:rustfmt-subtree, r=Mark-Simulacrum
Convert rustfmt from a submodule to a subtree

r? `@calebcartwright` cc `@Manishearth` `@Mark-Simulacrum`

The motivation is that submodule updates cause rustfmt to not be available on nightly a lot; most recently it was unavailable for over 10 days, causing the beta release to be delayed. Additionally this is much less work on the part of the rustfmt maintainers to keep the rustfmt compiling, since now people making breaking changes will be responsible for fixing them.

I kept the rustfmt git history so it looks like there are thousands of commits. The important commits are 851dee3af9~..pull/82208/head. This adds about 10 MB of git history, which is not terribly much compared to the 702 MB that already exist.

- Add `src/tools/rustfmt` to `x.py check`
- Fix CRLF issues with rustfmt tests (see commit for details)
- Use `rustc_private` instead of crates.io dependencies

  This was already switched upstream and would have landed in the next submodule bump anyway. This just updates Cargo.lock for rust-lang/rust.

- Add `yansi-term` to the list of allowed dependencies.

  This is a false positive - rustc doesn't actually use it, only rustfmt, but because it's activated by the cargo feature of a dependency, tidy gets confused. It's fairly innocuous in any case, it's used for color printing.
  This would have happened in the next submodule bump.

- Remove rustfmt from the list of toolstate tools.
- Give a hard error if testing or building rustfmt fails.
-  Update log to 0.4.14

   This avoids a warning about semicolons in macros; see the commit for details.

- Don't add tools to the sysroot when they finish building.

  This is the only change that could be considered a regression - this avoids a "colliding StableCrateId" error due to a bug in resolve (https://github.com/rust-lang/rust/issues/56935). The regression is that this rebuilds dependencies more often than strictly necessary. See the commit for details.

Fixes https://github.com/rust-lang/rust/issues/85226 (permanently). Closes https://github.com/rust-lang/rust/issues/82385. Helps with https://github.com/rust-lang/rust/issues/70651. Helps with https://github.com/rust-lang/rust/issues/80639.
2021-05-15 14:55:56 +00:00
bors 2a245f40a1 Auto merge of #85328 - GuillaumeGomez:rollup-exe9nbj, r=GuillaumeGomez
Rollup of 12 pull requests

Successful merges:

 - #84461 (rustdoc: Remove unnecessary `StripItem` wrapper)
 - #85067 (Minimize amount of fake `DefId`s used in rustdoc)
 - #85207 (Fix typo in comment)
 - #85215 (coverage bug fixes and some refactoring)
 - #85221 (dbg macro: Discuss use in tests, and slightly clarify)
 - #85246 (Miner code formatting)
 - #85253 (swap function order for better read flow)
 - #85256 (Fix display for "implementors" section)
 - #85268 (Use my real name)
 - #85278 (Improve match statements)
 - #85289 (Fix toggle position on mobile)
 - #85323 (Fix eslint errors)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2021-05-15 12:41:28 +00:00
Ralf Jung c96d531a92 fix version_str comment 2021-05-15 14:22:29 +02:00
Guillaume Gomez 46bc5526db
Rollup merge of #85323 - GuillaumeGomez:fix-eslint-errors, r=jsha
Fix eslint errors

I cherry-picked the two non-CI commits from #85285.

r? ```@jsha```
2021-05-15 13:29:57 +02:00
Guillaume Gomez 2b5ef25744
Rollup merge of #85289 - GuillaumeGomez:fix-toggle-position-mobile, r=jsha
Fix toggle position on mobile

Before:

![Screenshot from 2021-05-14 14-21-27](https://user-images.githubusercontent.com/3050060/118276475-fe210300-b4c7-11eb-94f8-4e2a4e10d91e.png)
![Screenshot from 2021-05-14 14-21-30](https://user-images.githubusercontent.com/3050060/118276479-feb99980-b4c7-11eb-85db-40e9df6e9abd.png)

After:

![Screenshot from 2021-05-14 15-16-54](https://user-images.githubusercontent.com/3050060/118276494-0416e400-b4c8-11eb-9479-d447928cfa62.png)
![Screenshot from 2021-05-14 15-16-59](https://user-images.githubusercontent.com/3050060/118276498-0416e400-b4c8-11eb-99f6-894276c62dfc.png)

r? ```@jsha```
2021-05-15 13:29:56 +02:00
Guillaume Gomez cd3d166021
Rollup merge of #85278 - ayushmishra2005:code-refactoring, r=jackh726
Improve match statements
2021-05-15 13:29:55 +02:00
Guillaume Gomez 1a926bf3c5
Rollup merge of #85268 - camelid:real-name, r=Mark-Simulacrum
Use my real name
2021-05-15 13:29:54 +02:00
Guillaume Gomez 5bfbabc892
Rollup merge of #85256 - GuillaumeGomez:fix-implementors-display, r=notriddle
Fix display for "implementors" section

Just saw this problem when going through docs:

![Screenshot from 2021-05-13 15-20-52](https://user-images.githubusercontent.com/3050060/118131978-766fc180-b3ff-11eb-86a8-7f6d22afa675.png)

This fix puts it back to normal:

![Screenshot from 2021-05-13 15-23-29](https://user-images.githubusercontent.com/3050060/118132006-7e2f6600-b3ff-11eb-9985-025a7b7c5216.png)

You can see it on the `TryFrom` page for example.

r? ```@Nemo157```
2021-05-15 13:29:53 +02:00
Guillaume Gomez 36b3c28497
Rollup merge of #85253 - RafaelKr:patch-1, r=varkor
swap function order for better read flow

I was reading this error message for the first time.

I was a little bit confused when reading that part:
```
foo.bar(); // we can now use this method since i32 implements the Foo trait
```

At the time I was reading `// we can now use this method` I wasn't sure why. It only made sense when reading on. So swapping these parts results in a better read flow.
2021-05-15 13:29:52 +02:00
Guillaume Gomez 57aa0d812a
Rollup merge of #85246 - ayushmishra2005:minor-reactoring, r=petrochenkov
Miner code formatting
2021-05-15 13:29:51 +02:00
Guillaume Gomez 5a8619b435
Rollup merge of #85221 - ijackson:dbg-doc-re-tests, r=joshtriplett
dbg macro: Discuss use in tests, and slightly clarify

As discussed in a tangent in #82778.

I chose to use [semantic newlines](https://rhodesmill.org/brandon/2012/one-sentence-per-line/) in the source text but I don't mind reformatting it.
2021-05-15 13:29:50 +02:00
Guillaume Gomez e611e64e3a
Rollup merge of #85215 - richkadel:ice-fixes-minus-dead-blocks, r=tmandry
coverage bug fixes and some refactoring

This replaces the relevant commits (2 and 3) from PR #85082, and also corrects an error querying for coverageinfo.

1. `coverageinfo` query needs to use the same MIR as codegen

I ran into an error trying to fix dead block coverage and realized the
`coverageinfo` query is getting a different MIR compared to the
codegenned MIR, which can sometimes be a problem during mapgen.

I changed that query to use the `InstandeDef` (which includes the
generic parameter substitutions, prosibly specific to const params)
instead of the `DefId` (without unknown/default const substitutions).

2. Simplified body_span and filtered span code

  Some code cleanup extracted from future (but unfinished) commit to fix
  coverage in attr macro functions.

3. Spanview needs the relevant body_span used for coverage

The coverage body_span doesn't always match the function body_span.

r? ```@tmandry```
2021-05-15 13:29:49 +02:00
Guillaume Gomez c4f81c12ea
Rollup merge of #85207 - andrewhalle:typo-rootseparator, r=kennytm
Fix typo in comment

missing space in "rootseparator"
2021-05-15 13:29:48 +02:00
Guillaume Gomez b68d5433c9
Rollup merge of #85067 - Stupremee:minimize-amount-of-fake-defids, r=jyn514,GuillaumeGomez
Minimize amount of fake `DefId`s used in rustdoc

Follow up from #84707, which minimizes the amount of fake defids to the smallest amount possible. Every `FakeDefId` that is now used in the rustdoc library must be preserved and can not be replaced with a normal `DefId`.
2021-05-15 13:29:47 +02:00
Guillaume Gomez 9682fa9dc4
Rollup merge of #84461 - jyn514:remove-strip-item, r=GuillaumeGomez
rustdoc: Remove unnecessary `StripItem` wrapper
2021-05-15 13:29:47 +02:00
Justus K 67d8d18b23
Minimize amount of fake `DefId`s used in rustdoc 2021-05-15 13:21:35 +02:00
Guillaume Gomez 18b7c0a00e Update rustdoc-js tools 2021-05-15 13:09:55 +02:00
Guillaume Gomez ccabd4eedf Fix eslint errors 2021-05-15 13:09:28 +02:00
Fabian Wolff 46d55d6549 Warn about unused pub fields in non-pub structs 2021-05-15 13:06:17 +02:00
bors b439be03c9 Auto merge of #84152 - sexxi-goose:insignificant_dtor, r=nikomatsakis
Insignificant destructors rfc 2229

- Adds new attribute `rustc_insignificant_dtor` to annotate the drop method.
- Adds a query to check if a type has a significant drop.
- Updates closure analysis to check for significant drops rather than just drop.

A type marked with the attribute `rustc_insignificant_dtor` is considered to not be significant. A drop is significant if it is implemented by the user or does anything that will have any observable behavior (other than freeing up memory).

https://github.com/rust-lang/project-rfc-2229/issues/35
2021-05-15 10:00:39 +00:00
bors c6dd87a6b4 Auto merge of #85311 - camelid:box-blanket-impl, r=jyn514
Box `Impl.blanket_impl` to reduce size

Blanket impls are probably not super common, and `Type` is a fairly
large type, so this should reduce `Impl`'s size by a lot: `Option<Type>`
is around 96 bytes, and `Option<Box<Type>>` is 8 bytes, so it's a big
difference!
2021-05-15 07:44:21 +00:00
bors 428636f954 Auto merge of #84997 - pietroalbini:ci-verify-channel, r=Mark-Simulacrum
Error out if a PR is sent to the wrong channel

It happened multiple times that a PR meant to go on beta ends up being opened (and occasionally merged) to master. This PR does two things:

* Moves the definition of the channel in `src/ci/channel` so it's easier for tools to read it. I was not sure whether to move it to `src/channel` (like `src/version`): ended up with `src/ci` as it's currently only used for CI, but I'm open to moving it to `src`. We'll need to update the release process after this.
* Adds a check on **non-bors** builds that errors out if the base branch is not the expected one for the currently defined channel. This will not cause problems for promotion PRs, as those PRs are meant to also update the channel name.

r? `@Mark-Simulacrum`
2021-05-15 05:20:49 +00:00
Dhruv Jauhar a7e1cec621 add new attribute rustc_insignificant_dtor and a query to check if a type has a significant drop 2021-05-14 22:57:33 -04:00
Caleb Cartwright 34368ec2aa ci(should-skip-this): only check commits when skip rule enabled 2021-05-14 21:55:19 -05:00
Joshua Nelson 08c7c61b9d should-skip-this: Check for changes between the master branch, not the previous commit.
The previous commit could be part of the current PR.
2021-05-14 21:55:03 -05:00
Joshua Nelson 56fa9b43c8 Run toolstate jobs when src/tools/rustfmt is modified.
Previously, this would be caught by a change for modified submodules;
now that rustfmt is no longer a submodule, the check needs to be
explicit.
2021-05-14 21:54:53 -05:00
Joshua Nelson 079d1c403f Update log to 0.4.14
This avoids the following warning:

```
warning: trailing semicolon in macro used in expression position
   --> /home/joshua/.local/lib/cargo/registry/src/github.com-1ecc6299db9ec823/log-0.4.11/src/macros.rs:152:45
    |
147 | / macro_rules! debug {
148 | |     (target: $target:expr, $($arg:tt)+) => (
149 | |         log!(target: $target, $crate::Level::Debug, $($arg)+);
150 | |     );
151 | |     ($($arg:tt)+) => (
152 | |         log!($crate::Level::Debug, $($arg)+);
    | |                                             ^
153 | |     )
154 | | }
    | |_- in this expansion of `debug!`
    |
   ::: src/tools/rustfmt/src/modules/visitor.rs:36:23
    |
36  |               Err(e) => debug!("{}", e),
    |                         --------------- in this macro invocation
    |
    = note: requested on the command line with `-W semicolon-in-expressions-from-macros`
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #79813 <https://github.com/rust-lang/rust/issues/79813>
```
2021-05-14 21:54:43 -05:00
Joshua Nelson b3494378aa Don't copy tool dependencies to the sysroot
This fixes the following error:

```
error: found crates (`serde_derive` and `serde_derive`) with colliding StableCrateId values.
   --> /home/joshua/.local/lib/cargo/registry/src/github.com-1ecc6299db9ec823/cargo_metadata-0.8.2/src/lib.rs:162:1
    |
162 | extern crate serde_derive;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
```

This is a bug in resolve (https://github.com/rust-lang/rust/issues/56935)
but it will be difficult to fix in the near future. This works around it
in the meantime by not copying serde_derive and other dependencies to
the sysroot when they're built for other tools. This rebuilds the
dependencies slightly more often than necessary, but avoids the crate
conflicts.

This can be reverted once #56935 is fixed.
2021-05-14 21:54:06 -05:00
Joshua Nelson 956e0bae58 Update bootstrap for in-tree rustfmt
- Add rustfmt to `x.py check`
- Update Cargo.lock
- Remove rustfmt from the toolstate list
- Make rustfmt an in-tree tool
- Give an error on `x.py test rustfmt` if rustfmt fails to build or if tests fail
- Don't call `save_toolstate` when testing rustfmt
2021-05-14 21:53:54 -05:00
Caleb Cartwright b2d45c0d4b Add 'src/tools/rustfmt/' from commit '7872306edf2e11a69aaffb9434088fd66b46a863'
git-subtree-dir: src/tools/rustfmt
git-subtree-mainline: e659b6de91
git-subtree-split: 7872306edf
2021-05-14 21:53:36 -05:00
Joshua Nelson e659b6de91 Delete rustfmt submodule 2021-05-14 21:52:54 -05:00
Caleb Cartwright 0e61f62bb5 add rustfmt crlf files to root gitattributes 2021-05-14 21:52:28 -05:00
Noah Lev f57537e5f3 Box `Impl.blanket_impl` to reduce size
Blanket impls are probably not super common, and `Type` is a fairly
large type, so this should reduce `Impl`'s size by a lot: `Option<Type>`
is around 96 bytes, and `Option<Box<Type>>` is 8 bytes, so it's a big
difference!
2021-05-14 17:45:41 -07:00
Caleb Cartwright 7872306edf chore: update gitattributes for files with windows style line endings 2021-05-14 18:50:25 -05:00
Guillaume Gomez dfc8b6094e Add test for toggle on mobile size 2021-05-14 22:25:50 +02:00
Guillaume Gomez 7eb95cd8e4 Unify toggle rules on smaller resolutions 2021-05-14 22:25:50 +02:00
Guillaume Gomez 0c02338a60 Move @media rules at the end so they override the other rules 2021-05-14 22:25:50 +02:00
bors 1025db84a6 Auto merge of #85211 - Aaron1011:metadata-invalid-span, r=michaelwoerister
Preserve `SyntaxContext` for invalid/dummy spans in crate metadata

Fixes #85197

We already preserved the `SyntaxContext` for invalid/dummy spans in the
incremental cache, but we weren't doing the same for crate metadata.
If an invalid (lo/hi from different files) span is written to the
incremental cache, we will decode it with a 'dummy' location, but keep
the original `SyntaxContext`. Since the crate metadata encoder was only
checking for `DUMMY_SP` (dummy location + root `SyntaxContext`),
the metadata encoder would treat it as a normal span, encoding the
`SyntaxContext`. As a result, the final span encoded to the metadata
would change across sessions, even if the crate itself was unchanged.

This could lead to an 'unstable fingerprint' ICE under the following conditions:
1. We compile a crate with an invalid span using incremental compilation. The metadata encoder discards the `SyntaxContext` since the span is invalid, while the incremental cache encoder preserves the `SyntaxContext`
2. From another crate, we execute a foreign query, decoding the invalid span from the metadata as `DUMMY_SP` (e.g. with `SyntaxContext::root()`). This span gets hashed into the query fingerprint. So far, this has always happened through the `optimized_mir` query.
3. We recompile the first crate using our populated incremental cache, without changing anything. We load the (previously) invalid span from our incremental cache - it gets converted to a span with a dummy (but valid) location, along with the original `SyntaxContext`. This span gets written out to the crate metadata - since it now has a valid location, we preserve its `SyntaxContext`.
4. We recompile the second crate, again using a populated incremental cache. We now re-run the foreign query `optimized_mir` - the foreign crate hash is unchanged, but we end up decoding a different span (it now ha a non-root `SyntaxContext`). This results in the fingerprint changing, resulting in an ICE.

This PR updates our encoding of spans in the crate metadata to mirror
the encoding of spans into the incremental cache. We now always encode a
`SyntaxContext`, and encode location information for spans with a
non-dummy location.
2021-05-14 16:58:30 +00:00
Guillaume Gomez 766de3a5e2 Fix toggle position on mobile 2021-05-14 15:16:29 +02:00
bors 75da570d78 Auto merge of #83640 - bjorn3:shared_metadata_reader, r=nagisa
Use the object crate for metadata reading

This allows sharing the metadata reader between cg_llvm, cg_clif and other codegen backends.

This is not currently useful for rlib reading with cg_spirv ([rust-gpu](https://github.com/EmbarkStudios/rust-gpu/)) as it uses tar rather than ar as .rlib format, but it is useful for dylib reading required for loading proc macros. (cc `@eddyb)`

The object crate is already trusted as dependency of libstd through backtrace. As far as I know it supports reading all object file formats used by targets for which we support rust dylibs with crate metadata, but I am not certain. If this happens to not be the case, I could keep using LLVM for reading dylib metadata.

Marked as WIP for a perf run and as it is based on #83637.
2021-05-14 12:58:58 +00:00
ayushmishra2005 27defcd14f Addressed PR coments 2021-05-14 17:30:26 +05:30