Make encode_info_for_trait_item use queries instead of accessing the HIR
This change avoids accessing the HIR on `encode_info_for_trait_item` and uses queries. We will need to execute this function for elements that have no HIR and by using queries we will be able to feed for definitions that have no HIR.
r? ``@oli-obk``
Better documentation for env::home_dir()'s broken behaviour
This improves the documentation to say *why* it was deprecated. The reason was because it reads `HOME` on Windows which is meaningless there. Note that the PR that deprecated it stated that returning an empty string if `HOME` is set to an empty string was a problem, however I can find no evidence that this is the case. `cd` handles it fine whereas if `HOME` is unset it gives an explicit `HOME not set` error.
* Original deprecation reason: https://internals.rust-lang.org/t/deprecate-or-break-fix-std-env-home-dir/7315
* Original deprecation PR: https://github.com/rust-lang/rust/pull/51656
See #71684
This commit partly undoes #104863, which combined the builtin lints pass
with other lints. This caused a slowdown, because often there are no
other lints, and it's faster to do a pass with a single lint directly
than it is to do a combined pass with a `passes` vector containing a
single lint.
I removed these in #105291, and subsequently learned they are necessary
for performance.
This commit reinstates them with the new and more descriptive names
`RuntimeCombined{Early,Late}LintPass`, similar to the existing passes
like `BuiltinCombinedEarlyLintPass`. It also adds some comments,
particularly emphasising how we have ways to combine passes at both
compile-time and runtime. And it moves some comments around.
Enable ThinLTO for rustc on `x86_64-apple-darwin`
Local measurements seemed to show an improvement on a couple benchmarks, so I'd like to test real CI builds, and see if the builder doesn't timeout with the expected slight increase in build times.
Let's start with x64 rustc ThinLTO, and then figure out the file structure to configure LLVM ThinLTO. Maybe we'll then try `aarch64` builds since that also looked good locally.
When encountering an unmet obligation that affects a method chain, like
in iterator chains where one of the links has the wrong associated
type, we point at every method call and mention their evaluated
associated type at that point to give context to the user of where
expectations diverged from the code as written.
```
note: the expression is of type `Map<std::slice::Iter<'_, {integer}>, [closure@$DIR/invalid-iterator-chain.rs:12:18: 12:21]>`
--> $DIR/invalid-iterator-chain.rs:12:14
|
LL | vec![0, 1]
| ---------- this expression has type `Vec<{integer}>`
LL | .iter()
| ------ associated type `std::iter::Iterator::Item` is `&{integer}` here
LL | .map(|x| { x; })
| ^^^^^^^^^^^^^^^ associated type `std::iter::Iterator::Item` is `()` here
```
Enable ThinLTO for rustc on x64 msvc
This applies the great work from `@bjorn3` and `@Kobzol` in https://github.com/rust-lang/rust/pull/101403 to x64 msvc.
Here are the local results for the try build `68c5c85ed759334a11f0b0e586f5032a23f85ce4`, compared to its parent `0a6b941df354c59b546ec4c0d27f2b9b0cb1162c`. Looking better than my previous local builds.
![image](https://user-images.githubusercontent.com/247183/198158039-98ebac0e-da0e-462e-8162-95e88345edb9.png)
(I can't show cycle counts, as that option is failing on the windows version of the perf collector, but I'll try to analyze and debug this soon)
This will be the first of a few tests for rustc / llvm / both ThinLTO on the windows and mac targets.
Don't internalize __llvm_profile_counter_bias
Currently, LLVM profiling runtime counter relocation cannot be used by rust during LTO because symbols are being internalized before all symbol information is known.
This mode makes LLVM emit a __llvm_profile_counter_bias symbol which is referenced by the profiling initialization, which itself is pulled in by the rust driver here [1].
It is enabled with -Cllvm-args=-runtime-counter-relocation for platforms which are opt-in to this mode like Linux. On these platforms there will be no link error, rather just surprising behavior for a user which request runtime counter relocation. The profiling runtime will not see that symbol go on as if it were never there. On Fuchsia, the profiling runtime must have this symbol which will cause a hard link error.
As an aside, I don't have enough context as to why rust's LTO model is how it is. AFAICT, the internalize pass is only safe to run at link time when all symbol information is actually known, this being an example as to why. I think special casing this symbol as a known one that LLVM can emit which should not have it's visbility de-escalated should be fine given how seldom this pattern of defining an undefined symbol to get initilization code pulled in is. From a quick grep, __llvm_profile_runtime is the only symbol that rustc does this for.
[1] 0265a3e93b/compiler/rustc_codegen_ssa/src/back/linker.rs (L598)
rustdoc: Only hide lines starting with `#` in rust code blocks
Fixes https://github.com/rust-lang/rust/issues/105527.
So before approving, this is a big question: in rust code blocks, in a line starts with a `#`, we hide it in the output. However, should we do the same for non-rust code blocks too? I think it's a bit problematic to do it because `#` can be used for many things but I prefer to check first with everyone (might also be worth updating documentation too).
cc ``@rust-lang/rustdoc``
r? ``@notriddle``
compiler: remove unnecessary imports and qualified paths
Some of these imports were necessary before Edition 2021, others were already in the prelude.
I hope it's fine that this PR is so spread-out across files :/
rustdoc: Prevent auto/blanket impl retrieval if there were compiler errors
Fixes https://github.com/rust-lang/rust/issues/105404.
I'm not sure happy about this fix but since it's how passes work (ie, even if there are errors, it runs all passes), I think it's fine as is.
Just as a sidenote: I also gave a try to prevent running all passes in case there were compiler errors but then a lot of rustdoc tests were failing so I went for this fix instead.
r? `@notriddle`
Some method confirmation code nits
1. Make some pick methods take `&self` instead of `&mut` to avoid some cloning
2. Pass some values by reference to avoid some cloning
3. Rename a few variables here and there