Rollup of 7 pull requests
Successful merges:
- #114930 (Automatically add OS labels to std PRs)
- #115053 (docs: Add example, reference link for `type` keyword.)
- #115092 (Add generics_of to smir)
- #115096 (Add regression test for not `memcpy`ing padding bytes)
- #115100 (Add support for `ptr::write`s for the `invalid_reference_casting` lint)
- #115114 (Contents of reachable statics is reachable)
- #115122 (Fix clippy lint for identical `if`/`else` contraining `?` expressions)
r? `@ghost`
`@rustbot` modify labels: rollup
Add support for `ptr::write`s for the `invalid_reference_casting` lint
This PR adds support for `ptr::write` and others for the `invalid_reference_casting` lint.
Detecting instances where instead of using the deref (`*`) operator to assign someone uses `ptr::write`, `ptr::write_unaligned` or `ptr::write_volatile`.
```rust
let data_len = 5u64;
std::ptr::write(
std::mem::transmute::<*const u64, *mut u64>(&data_len),
new_data_len,
);
```
r? ``@est31``
Add regression test for not `memcpy`ing padding bytes
Closes#56297
See this comparison: https://rust.godbolt.org/z/jjzfonfcE
I don't have any experience with codegen tests, I hope this is correct
Automatically add OS labels to std PRs
I'd love to have `library/std/src/sys` PRs that touch Windows stuff to have the `O-windows` label for easier discovery (and rediscovery). While I'm here I added a couple of other auto OS labels. Perhaps `O-unix` is a little too broad but it's hard to be more specific and I think it's still useful insomuch as POSIX is a thing.
r? libs
Update the links for Stabilized APIs in 1.72.0
* Use `stable` instead of `nightly` paths.
* Fix the anchors for `CStr::to_*` links.
r? `@Mark-Simulacrum`
Update cargo
3 commits in 80eca0e58fb2ff52c1e94fc191b55b37ed73e0e4..2cc50bc0b63ad20da193e002ba11d391af0104b7
2023-08-19 00:52:06 +0000 to 2023-08-22 22:43:08 +0000
- config: merge lists in precedence order (rust-lang/cargo#12515)
- ci: test `resolver-tests` in a separate job (rust-lang/cargo#12540)
- refactor: Use clap to suggest alternative argument for unsupported arguments (rust-lang/cargo#12529)
r? ghost
Don't do intra-pass validation on MIR shims
Fixes#114375
In the test that was committed, we end up generating the drop shim for `struct Foo` that looks like:
```
fn std::ptr::drop_in_place(_1: *mut Foo) -> () {
let mut _0: ();
bb0: {
goto -> bb5;
}
bb1: {
return;
}
bb2 (cleanup): {
resume;
}
bb3: {
goto -> bb1;
}
bb4 (cleanup): {
drop(((*_1).0: foo::WrapperWithDrop<()>)) -> [return: bb2, unwind terminate];
}
bb5: {
drop(((*_1).0: foo::WrapperWithDrop<()>)) -> [return: bb3, unwind: bb2];
}
}
```
In `bb4` and `bb5`, we assert that `(*_1).0` has type `WrapperWithDrop<()>`. However, In a user-facing param env, the type is actually `WrapperWithDrop<Tait>`. These types are not equal in a user-facing param-env (and can't be made equal even if we use `DefiningAnchor::Bubble`, since it's a non-local TAIT).
Use the same DISubprogram for each instance of the same inlined function within a caller
# Issue Details:
The call to `panic` within a function like `Option::unwrap` is translated to LLVM as a `tail call` (as it will never return), when multiple calls to the same function like this is inlined LLVM will notice the common `tail call` block (i.e., loading the same panic string + location info and then calling `panic`) and merge them together.
When merging these instructions together, LLVM will also attempt to merge the debug locations as well, but this fails (i.e., debug info is dropped) as Rust emits a new `DISubprogram` at each inline site thus LLVM doesn't recognize that these are actually the same function and so thinks that there isn't a common debug location.
As an example of this when building for x86_64 Windows (note the lack of `.cv_loc` before the call to `panic`, thus it will be attributed to the same line at the `addq` instruction):
```
.cv_loc 0 1 23 0 # src\lib.rs:23:0
addq $40, %rsp
retq
leaq .Lalloc_f570dea0a53168780ce9a91e67646421(%rip), %rcx
leaq .Lalloc_629ace53b7e5b76aaa810d549cc84ea3(%rip), %r8
movl $43, %edx
callq _ZN4core9panicking5panic17h12e60b9063f6dee8E
int3
```
# Fix Details:
Cache the `DISubprogram` emitted for each inlined function instance within a caller so that this can be reused if that instance is encountered again, this also requires caching the `DILexicalBlock` and `DIVariable` objects to avoid creating duplicates.
After this change the above assembly now looks like:
```
.cv_loc 0 1 23 0 # src\lib.rs:23:0
addq $40, %rsp
retq
.cv_inline_site_id 5 within 0 inlined_at 1 0 0
.cv_inline_site_id 6 within 5 inlined_at 1 12 0
.cv_loc 6 2 935 0 # library\core\src\option.rs:935:0
leaq .Lalloc_5f55955de67e57c79064b537689facea(%rip), %rcx
leaq .Lalloc_e741d4de8cb5801e1fd7a6c6795c1559(%rip), %r8
movl $43, %edx
callq _ZN4core9panicking5panic17hde1558f32d5b1c04E
int3
```
triagebot: add dependency licensing pings
If a compiler dependency is added, it's probably worth having that double-checked by compiler co-leads to confirm the licensing is okay.
r? `@wesleywiser`
Always use `os-release` rather than `/lib` to detect `NixOS` (bootstrap)
[Two users over on zulip](https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/Bootstrapping.20on.20NixOS) bumped into issues where NixOS wasn't being properly detected.
I believe this was caused by the presence of `/lib` on their machines. `/lib` is not standard on NixOS but can still be created by users or scripts.
We are already checking `/etc/os-release`. The presence of `ID=nixos` in it's output should be trustworthy and we shouldn't then go on to also check for `/lib`.
Add disclaimer on size assertion macro
Sometimes people are inspired by rustc to add size assertions to their code and copy the macro. This is bad because it causes hard build errors. rustc happens to be special where it makes this okay.
For example, see #115028 (not sure whether they were directly inspired by this function), but I think I've also seen other cases.
Warn on elided lifetimes in associated constants (`ELIDED_LIFETIMES_IN_ASSOCIATED_CONSTANT`)
Elided lifetimes in associated constants (in impls) erroneously resolve to fresh lifetime parameters on the impl since #97313. This is not correct behavior (see #38831).
I originally opened #114716 to fix this, but given the time that has passed, the crater results seem pretty bad: https://github.com/rust-lang/rust/pull/114716#issuecomment-1682091952
This PR alternatively implements a lint against this behavior, and I'm hoping to bump this to deny in a few versions.
fix#113702 emit a proper diagnostic message for unstable lints passed from CLI
Current output:
```bash
$ build/host/stage1/bin/rustc hello.rs -Wunnameable_types
warning: unknown lint: `unnameable_types`
|
= note: the `unnameable_types` lint is unstable
= note: see issue #48054 <https://github.com/rust-lang/rust/issues/48054> for more information
= help: add `-Zcrate-attr="feature(type_privacy_lints)"` to the command-line options to enable
= note: `#[warn(unknown_lints)]` on by default
warning: 1 warning emitted
```
Previously, the feature gate diagnostic message is like below, which is the same as the message for unstable lints from the root module.
```shell
= help: add `#![feature(type_privacy_lints)]` to the crate attributes to enable
```
Fixes https://github.com/rust-lang/rust/issues/113702
Redefine the pluralize macro's arm
Redefine the unintuitive pluralize macro's arm because of the negation. The initial code starts with check if count is not 1, which is confusing and unintuitive.
The arm shoud start with checking,
- if "count" `is 1` then, append `""` (empty string) - indicate as singular
- Then check if "count" `is not 1` (more than 1), append `"s"` - indicate as plural
Before:
```rs
// This arm is abit confusing since it start with checking, if "count" is more than 1, append "s".
($x:expr) => {
if $x != 1 { "s" } else { "" }
};
```
After:
```rs
// Pluralize based on count (e.g., apples)
($x:expr) => {
if $x == 1 { "" } else { "s" }
};
```
[Two users over on zulip](https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/Bootstrapping.20on.20NixOS) bumped into issues where NixOS wasn't being properly detected.
I believe this was caused by the presence of `/lib` on their machines. `/lib` is not standard on NixOS but can still be created by users or scripts.
We are already checking `/etc/os-release`. The presence of `ID=nixos` in it's output should be trustworthy and we shouldn't then go on to also check for `/lib`.
Remove myself from review rotation
I'll.. still be around, just not as active as I had been. I'm not adding myself to `users_on_vacation`, because anyone should still feel free to r? me if they want a specific review from me.
Sometimes people are inspired by rustc to add size assertions to their
code and copy the macro. This is bad because it causes hard build
errors. rustc happens to be special where it makes this okay.
Reassign sparc-unknown-none-elf to tier 3
It should never have been moved to tier 2. It is a new platform and the maintainer has agreed to do tier 3 maintenance for it, not tier 2.
r? `@jonathanpallant`
Fix table issues in platform support documentation (closes#115047)
mdBook needs an empty line before and after the table block.
In addition, in the tier-3 list three targets forgot about the host column and therefore showed the notes in the host column.
Closes#115047
