Dylan DPC [Mon, 15 Mar 2021 15:22:58 +0000 (16:22 +0100)]
Rollup merge of #83132 - Aaron1011:fix/incr-cache-dummy, r=estebank
Don't encode file information for span with a dummy location
Fixes #83112
The location information for a dummy span isn't real, so don't encode
it. This brings the incr comp cache code into line with the Span
`StableHash` impl, which doesn't hash the location information for dummy
spans.
Previously, we would attempt to load the 'original' file from a dummy
span - if the file id changed (e.g. due to being moved on disk), we would get an
ICE, since the Span was still valid due to its hash being unchanged.
Dylan DPC [Mon, 15 Mar 2021 15:22:57 +0000 (16:22 +0100)]
Rollup merge of #83127 - Aaron1011:time-macros-impl-warn, r=petrochenkov
Introduce `proc_macro_back_compat` lint, and emit for `time-macros-impl`
Now that future-incompat-report support has landed in nightly Cargo, we
can start to make progress towards removing the various proc-macro
back-compat hacks that have accumulated in the compiler.
This PR introduces a new lint `proc_macro_back_compat`, which results in
a future-incompat-report entry being generated. All proc-macro
back-compat warnings will be grouped under this lint. Note that this
lint will never actually become a hard error - instead, we will remove
the special cases for various macros, which will cause older versions of
those crates to emit some other error.
I've added code to fire this lint for the `time-macros-impl` case. This
is the easiest case out of all of our current back-compat hacks - the
crate was renamed to `time-macros`, so seeing a filename with
`time-macros-impl` guarantees that an older version of the parent `time`
crate is in use.
When Cargo's future-incompat-report feature gets stabilized, affected
users will start to see future-incompat warnings when they build their
crates.
Dylan DPC [Mon, 15 Mar 2021 15:22:52 +0000 (16:22 +0100)]
Rollup merge of #83098 - camelid:more-doc-attr-check, r=davidtwco
Find more invalid doc attributes
- Lint on `#[doc(123)]`, `#[doc("hello")]`, etc.
- Lint every attribute; e.g., will now report two warnings for `#[doc(foo, bar)]`
- Add hyphen to "crate level"
- Display paths like `#[doc(foo::bar)]` correctly instead of as an empty string
bors [Mon, 15 Mar 2021 08:49:25 +0000 (08:49 +0000)]
Auto merge of #82999 - cuviper:rustc-rayon-0.3.1, r=Mark-Simulacrum
Update to rustc-rayon 0.3.1
This pulls in rust-lang/rustc-rayon#8 to fix #81425. (h/t `@ammaraskar)`
That revealed weak constraints on `rustc_arena::DropArena`, because its
`DropType` was holding type-erased raw pointers to generic `T`. We can
implement `Send` for `DropType` (under `cfg(parallel_compiler)`) by
requiring all `T: Send` before they're type-erased.
bors [Mon, 15 Mar 2021 06:20:24 +0000 (06:20 +0000)]
Auto merge of #83074 - Aaron1011:new-sort-fix, r=jackh726
Avoid sorting predicates by `DefId`
Fixes issue #82920
Even if an item does not change between compilation sessions, it may end
up with a different `DefId`, since inserting/deleting an item affects
the `DefId`s of all subsequent items. Therefore, we use a `DefPathHash`
in the incremental compilation system, which is stable in the face of
changes to unrelated items.
In particular, the query system will consider the inputs to a query to
be unchanged if any `DefId`s in the inputs have their `DefPathHash`es
unchanged. Queries are pure functions, so the query result should be
unchanged if the query inputs are unchanged.
Unfortunately, it's possible to inadvertantly make a query result
incorrectly change across compilations, by relying on the specific value
of a `DefId`. Specifically, if the query result is a slice that gets
sorted by `DefId`, the precise order will depend on how the `DefId`s got
assigned in a particular compilation session. If some definitions end up
with different `DefId`s (but the same `DefPathHash`es) in a subsequent
compilation session, we will end up re-computing a *different* value for
the query, even though the query system expects the result to unchanged
due to the unchanged inputs.
It turns out that we have been sorting the predicates computed during
`astconv` by their `DefId`. These predicates make their way into the
`super_predicates_that_define_assoc_type`, which ends up getting used to
compute the vtables of trait objects. This, re-ordering these predicates
between compilation sessions can lead to undefined behavior at runtime -
the query system will re-use code built with a *differently ordered*
vtable, resulting in the wrong method being invoked at runtime.
This PR avoids sorting by `DefId` in `astconv`, fixing the
miscompilation. However, it's possible that other instances of this
issue exist - they could also be easily introduced in the future.
To fully fix this issue, we should
1. Turn on `-Z incremental-verify-ich` by default. This will cause the
compiler to ICE whenver an 'unchanged' query result changes between
compilation sessions, instead of causing a miscompilation.
2. Remove the `Ord` impls for `CrateNum` and `DefId`. This will make it
difficult to introduce ICEs in the first place.
Aaron Hill [Sun, 14 Mar 2021 20:55:59 +0000 (16:55 -0400)]
Introduce `proc_macro_back_compat` lint, and emit for `time-macros-impl`
Now that future-incompat-report support has landed in nightly Cargo, we
can start to make progress towards removing the various proc-macro
back-compat hacks that have accumulated in the compiler.
This PR introduces a new lint `proc_macro_back_compat`, which results in
a future-incompat-report entry being generated. All proc-macro
back-compat warnings will be grouped under this lint. Note that this
lint will never actually become a hard error - instead, we will remove
the special cases for various macros, which will cause older versions of
those crates to emit some other error.
I've added code to fire this lint for the `time-macros-impl` case. This
is the easiest case out of all of our current back-compat hacks - the
crate was renamed to `time-macros`, so seeing a filename with
`time-macros-impl` guarantees that an older version of the parent `time`
crate is in use.
When Cargo's future-incompat-report feature gets stabilized, affected
users will start to see future-incompat warnings when they build their
crates.
Aaron Hill [Sun, 14 Mar 2021 23:03:16 +0000 (19:03 -0400)]
Don't encode file information for span with a dummy location
Fixes #83112
The location information for a dummy span isn't real, so don't encode
it. This brings the incr comp cache code into line with the Span
`StableHash` impl, which doesn't hash the location information for dummy
spans.
Previously, we would attempt to load the 'original' file from a dummy
span - if the file id changed (e.g. due to being moved on disk), we would get an
ICE, since the Span was still valid due to its hash being unchanged.
bors [Sun, 14 Mar 2021 04:09:02 +0000 (04:09 +0000)]
Auto merge of #83105 - JohnTitor:rollup-tqpm8pb, r=JohnTitor
Rollup of 10 pull requests
Successful merges:
- #81465 (Add documentation about formatting `Duration` values)
- #82121 (Implement Extend and FromIterator for OsString)
- #82617 (Document `everybody_loops`)
- #82789 (Get with field index from pattern slice instead of directly indexing)
- #82798 (Rename `rustdoc` to `rustdoc::all`)
- #82804 (std: Fix a bug on the wasm32-wasi target opening files)
- #82943 (Demonstrate best practice for feeding stdin of a child processes)
- #83066 (Add `reverse` search alias for Iterator::rev())
- #83070 (Update cargo)
- #83081 (Fix panic message of `assert_failed_inner`)
Yuki Okushi [Sun, 14 Mar 2021 04:07:36 +0000 (13:07 +0900)]
Rollup merge of #83070 - ehuss:update-cargo, r=ehuss
Update cargo
7 commits in 970bc67c3775781b9708c8a36893576b9459c64a..32da9eaa5de5be241cf8096ca6b749a157194f77
2021-03-07 18:09:40 +0000 to 2021-03-13 01:18:40 +0000
- Fix logic for determining prefer-dynamic for a dylib. (rust-lang/cargo#9252)
- Fix issue with filtering exclusive target dependencies. (rust-lang/cargo#9255)
- Update pkgid-spec docs. (rust-lang/cargo#9249)
- Wordsmith the edition documentation a bit more (rust-lang/cargo#9233)
- Package ID specification urls must contain a host (rust-lang/cargo#9188)
- Add documentation for JSON message_path. (rust-lang/cargo#9247)
- Fix filter_platform to run on targets other than x86. (rust-lang/cargo#9246)
Yuki Okushi [Sun, 14 Mar 2021 04:07:34 +0000 (13:07 +0900)]
Rollup merge of #82943 - kornelski:threadstdio, r=joshtriplett
Demonstrate best practice for feeding stdin of a child processes
Documentation change.
It's possible to create a deadlock with stdin/stdout I/O on a single thread:
* the child process may fill its stdout buffer, and have to wait for the parent process to read it,
* but the parent process may be waiting until its stdin write finishes before reading the stdout.
Therefore, the parent process should use separate threads for writing and reading.
These examples are not deadlocking in practice, because they use short strings, but I think it's better to demonstrate code that works even for long writes. The problem is non-obvious and tricky to debug (it seems that even libstd has a similar issue: #45572).
This also demonstrates how to use stdio with threads: it's not obvious that `.take()` can be used to avoid fighting with the borrow checker.
Yuki Okushi [Sun, 14 Mar 2021 04:07:33 +0000 (13:07 +0900)]
Rollup merge of #82804 - alexcrichton:fix-wasi, r=pnkfelix
std: Fix a bug on the wasm32-wasi target opening files
This commit fixes an issue pointed out in #82758 where LTO changed the
behavior of a program. It turns out that LTO was not at fault here, it
simply uncovered an existing bug. The bindings to
`__wasilibc_find_relpath` assumed that the relative portion of the path
returned was always contained within thee input `buf` we passed in. This
isn't actually the case, however, and sometimes the relative portion of
the path may reference a sub-portion of the input string itself.
The fix here is to use the relative path pointer coming out of
`__wasilibc_find_relpath` as the source of truth. The `buf` used for
local storage is discarded in this function and the relative path is
copied out unconditionally. We might be able to get away with some
`Cow`-like business or such to avoid the extra allocation, but for now
this is probably the easiest patch to fix the original issue.
Yuki Okushi [Sun, 14 Mar 2021 04:07:31 +0000 (13:07 +0900)]
Rollup merge of #82789 - csmoe:issue-82772, r=estebank
Get with field index from pattern slice instead of directly indexing
Closes #82772
r? ``@estebank``
https://github.com/rust-lang/rust/pull/82789#issuecomment-796921977
> ``@estebank`` So the real cause is we only generate single pattern for Box here
https://github.com/csmoe/rust/blob/615b03aeaa8ce9819de7828740ab3cd7def4fa76/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs#L1130-L1132
But in the replacing function, it tries to index on the 1-length pattern slice with field 1, thus out of bounds.
https://github.com/csmoe/rust/blob/615b03aeaa8ce9819de7828740ab3cd7def4fa76/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs#L1346
I use `clap` for command line argument parsing, which collects these `-e` commands into a `Vec<OsString>`. To pass these commands to the interpreter for `Eval`, I need to join them together. Combining these impls with `Iterator::intersperse` https://github.com/rust-lang/rust/issues/79524 would enable me to build a single bit of Ruby code.
Currently, I'm doing something like:
```rust
let mut commands = commands.into_iter();
let mut buf = if let Some(command) = commands.next() {
command
} else {
return Ok(Ok(()));
};
for command in commands {
buf.push("\n");
buf.push(command);
}
```
If there's interest, I'd also like to add impls for `Cow<'a, OsStr>`, which would avoid allocating the `"\n"` `OsString` in the concatenate + intersperse use case.
Camelid [Sun, 14 Mar 2021 00:36:38 +0000 (16:36 -0800)]
Update `rustdoc-ui` versions of the `doc-attr` test
It seems there are two copies of it: one in `src/test/ui/attributes/`
and one in `src/test/rustdoc-ui/`. I'm guessing this is to test that the
lint is emitted both when you run the compiler and when you run rustdoc.
Camelid [Sat, 13 Mar 2021 21:13:27 +0000 (13:13 -0800)]
Refactor `check_doc_attrs` body
This change makes it easier to follow the control flow.
I also moved the end-of-line comments attached to some symbols to before
the symbol listing. This allows rustfmt to format the code; otherwise no
formatting occurs (see rust-lang/rustfmt#4750).
Aaron Hill [Fri, 12 Mar 2021 22:53:02 +0000 (17:53 -0500)]
Avoid sorting predicates by `DefId`
Fixes issue #82920
Even if an item does not change between compilation sessions, it may end
up with a different `DefId`, since inserting/deleting an item affects
the `DefId`s of all subsequent items. Therefore, we use a `DefPathHash`
in the incremental compilation system, which is stable in the face of
changes to unrelated items.
In particular, the query system will consider the inputs to a query to
be unchanged if any `DefId`s in the inputs have their `DefPathHash`es
unchanged. Queries are pure functions, so the query result should be
unchanged if the query inputs are unchanged.
Unfortunately, it's possible to inadvertantly make a query result
incorrectly change across compilations, by relying on the specific value
of a `DefId`. Specifically, if the query result is a slice that gets
sorted by `DefId`, the precise order will depend on how the `DefId`s got
assigned in a particular compilation session. If some definitions end up
with different `DefId`s (but the same `DefPathHash`es) in a subsequent
compilation session, we will end up re-computing a *different* value for
the query, even though the query system expects the result to unchanged
due to the unchanged inputs.
It turns out that we have been sorting the predicates computed during
`astconv` by their `DefId`. These predicates make their way into the
`super_predicates_that_define_assoc_type`, which ends up getting used to
compute the vtables of trait objects. This, re-ordering these predicates
between compilation sessions can lead to undefined behavior at runtime -
the query system will re-use code built with a *differently ordered*
vtable, resulting in the wrong method being invoked at runtime.
This PR avoids sorting by `DefId` in `astconv`, fixing the
miscompilation. However, it's possible that other instances of this
issue exist - they could also be easily introduced in the future.
To fully fix this issue, we should
1. Turn on `-Z incremental-verify-ich` by default. This will cause the
compiler to ICE whenver an 'unchanged' query result changes between
compilation sessions, instead of causing a miscompilation.
2. Remove the `Ord` impls for `CrateNum` and `DefId`. This will make it
difficult to introduce ICEs in the first place.
Aaron Hill [Thu, 11 Mar 2021 06:12:07 +0000 (01:12 -0500)]
Always run `incremental_verify_ich` when re-computing query results
Issue #82920 showed that the kind of bugs caught by this flag have
soundness implications.
This causes performance regressions of up to 15.2% during incremental
compilation, but this is necessary to catch miscompilations caused by
bugs in query implementations.
bors [Sat, 13 Mar 2021 09:47:07 +0000 (09:47 +0000)]
Auto merge of #82878 - sexxi-goose:repr_packed, r=nikomatsakis
2229: Handle capturing a reference into a repr packed struct
RFC 1240 states that it is unsafe to capture references into a
packed-struct. This PR ensures that when a closure captures a precise
path, we aren't violating this safety constraint.
To acheive so we restrict the capture precision to the struct itself.
An interesting edge case where we decided to restrict precision:
```rust
struct Foo(String);
let foo: Foo;
let c = || {
println!("{}", foo.0);
let x = foo.0;
}
```
Given how closures get desugared today, foo.0 will be moved into the
closure, making the `println!`, safe. However this can be very subtle
and also will be unsafe if the closure gets inline.
bors [Sat, 13 Mar 2021 04:38:39 +0000 (04:38 +0000)]
Auto merge of #82436 - osa1:issue80258, r=nikomatsakis
Allow calling *const methods on *mut values
This allows `*const` methods to be called on `*mut` values.
TODOs:
- [x] ~~Remove debug logs~~ Done.
- [x] ~~I haven't tested, but I think this currently won't work when the `self` value has type like `&&&&& *mut X` because I don't do any autoderefs when probing. To fix this the new code in `rustc_typeck::check::method::probe` needs to reuse `pick_method` somehow as I think that's the function that autoderefs.~~ This works, because autoderefs are done before calling `pick_core`, in `method_autoderef_steps`, called by `probe_op`.
- [x] ~~I should probably move the new `Pick` to `pick_autorefd_method`. If not, I should move it to its own function.~~ Done.
- [ ] ~~Test this with a `Pick` with `to_ptr = true` and `unsize = true`.~~ I think this case cannot happen, because we don't have any array methods with `*mut [X]` receiver. I should confirm that this is true and document this. I've placed two assertions about this.
- [x] ~~Maybe give `(Mutability, bool)` a name and fields~~ I now have a `to_const_ptr` field in `Pick`.
- [x] ~~Changes in `adjust_self_ty` is quite hacky. The problem is we can't deref a pointer, and even if we don't have an adjustment to get the address of a value, so to go from `*mut` to `*const` we need a special case.~~ There's still a special case for `to_const_ptr`, but I'm not sure if we can avoid this.
- [ ] Figure out how `reached_raw_pointer` stuff is used. I suspect only for error messages.
bors [Sat, 13 Mar 2021 02:08:33 +0000 (02:08 +0000)]
Auto merge of #83067 - JohnTitor:rollup-0wo338i, r=JohnTitor
Rollup of 6 pull requests
Successful merges:
- #82984 (Simplify ast block lowering)
- #83012 (Update Clippy)
- #83020 (Emit the enum range assumption if the range only contains one element)
- #83037 (Support merge_functions option in NewPM since LLVM >= 12)
- #83052 (updated vulnerable deps)
- #83059 (Allow configuring `rustdoc --disable-minification` in config.toml)
Yuki Okushi [Sat, 13 Mar 2021 00:44:46 +0000 (09:44 +0900)]
Rollup merge of #83052 - klensy:dep-update, r=Mark-Simulacrum
updated vulnerable deps
* Updated signal-hook-registry 1.2.1 to 1.2.2, as it drops dependency on vulnerable arc-swap 0.4.7 https://rustsec.org/advisories/RUSTSEC-2020-0091
* Updated generic-array 0.12.3 to 0.12.4, vuln https://rustsec.org/advisories/RUSTSEC-2020-0146
* Updated sized-chunks 0.6.2 to 0.6.4, vuln https://rustsec.org/advisories/RUSTSEC-2020-0041 fixed in 0.6.3, in 0.6.4 fixed some UB https://github.com/bodil/sized-chunks/blob/master/CHANGELOG.md#064---2021-02-17
bors [Fri, 12 Mar 2021 23:27:23 +0000 (23:27 +0000)]
Auto merge of #83022 - m-ou-se:mem-replace-no-swap, r=nagisa
Don't implement mem::replace with mem::swap.
`swap` is a complicated operation, so this changes the implementation of `replace` to use `read` and `write` instead.
See https://github.com/rust-lang/rust/pull/83019.
I wrote there:
> Implementing the simpler operation (replace) with the much more complicated operation (swap) doesn't make a whole lot of sense. `replace` is just read+write, and the primitive for moving out of a `&mut`. `swap` is for doing that to *two* `&mut` at the same time, which is both more niche and more complicated (as shown by `swap_nonoverlapping_bytes`).
This could be especially interesting for `Option<VeryLargeStruct>::take()`, since swapping such a large structure with `swap_nonoverlapping_bytes` is going to be much less efficient than `ptr::write()`'ing a `None`.
But also for small values where `swap` just reads/writes using temporary variable, this makes a `replace` or `take` operation simpler:
![image](https://user-images.githubusercontent.com/783247/110839393-c7e6bd80-82a3-11eb-97b7-28acb14deffd.png)
bors [Fri, 12 Mar 2021 11:46:50 +0000 (11:46 +0000)]
Auto merge of #82422 - petrochenkov:allunst, r=oli-obk
expand: Do not allocate `Lrc` for `allow_internal_unstable` list unless necessary
This allocation is done for any macro defined in the current crate, or used from a different crate.
EDIT: This also removes an `Lrc` increment from each *use* of such macro, which may be more significant.
Noticed when reviewing https://github.com/rust-lang/rust/pull/82367.
This probably doesn't matter, but let's do a perf run.