On demandify region mapping
This is an adaptation of @cramertj's PR. I am sort of tempted to keep simplifying it, but also tempted to land it so and we can refactor more in follow-up PRs. As is, it does the following things:
- makes the region-maps an on-demand query, per function `tcx.region_maps(def_id)`
- interns code extents instead of of having them be integers
- remove the "root region extent" and (to some extent) item extents; instead we use `Option<CodeExtent<'tcx>>` in a few places (no space inefficiency since `CodeExtent<'tcx>` is now a pointer).
I'm not entirely happy with the way I have it setup though. Here are some of the changes I was considering (I'm not sure if they would work out well):
1. Removing `item_extents` entirely -- they are rarely used now, because most of the relevant places now accept an `Option<Region<'tcx>>` or an `Option<CodeExtent<'tcx>>`, but I think still used in a few places.
2. Merging `RegionMaps` into the typeck tables, instead of having it be its own query.
3. Change `CodeExtent<'tcx>` to store the parent pointer. This would mean that fewer places in the code actually *need* a `RegionMaps` anyhow, since most of them just want to be able to walk "up the tree". On the other hand, you wouldn't be able to intern a `CodeExtent<'tcx>` for some random node-id, you'd need to look it up in the table (since there'd be more information).
Most of this code is semi-temporary -- I expect it to largely go away as we move to NLL -- so I'm also not *that* concerned with making it perfect.
r? @eddyb
std: Don't cache stdio handles on Windows
This alters the stdio code on Windows to always call `GetStdHandle` whenever the
stdio read/write functions are called as this allows us to track changes to the
value over time (such as if a process calls `SetStdHandle` while it's running).
Closes#40490
This commit deletes the internal liblog in favor of the implementation that
lives on crates.io. Similarly it's also setting a convention for adding crates
to the compiler. The main restriction right now is that we want compiler
implementation details to be unreachable from normal Rust code (e.g. requires a
feature), and by default everything in the sysroot is reachable via `extern
crate`.
The proposal here is to require that crates pulled in have these lines in their
`src/lib.rs`:
#![cfg_attr(rustbuild, feature(staged_api, rustc_private))]
#![cfg_attr(rustbuild, unstable(feature = "rustc_private", issue = "27812"))]
This'll mean that by default they're not using these attributes but when
compiled as part of the compiler they do a few things:
* Mark themselves as entirely unstable via the `staged_api` feature and the
`#![unstable]` attribute.
* Allow usage of other unstable crates via `feature(rustc_private)` which is
required if the crate relies on any other crates to compile (other than std).
This alters the stdio code on Windows to always call `GetStdHandle` whenever the
stdio read/write functions are called as this allows us to track changes to the
value over time (such as if a process calls `SetStdHandle` while it's running).
Closes#40490
macros: improve the `TokenStream` quoter
This PR
- renames the `TokenStream` quoter from `qquote!` to `quote!`,
- uses `$` instead of `unquote` (e.g. `let toks: TokenStream = ...; quote!([$toks])`),
- allows unquoting `Token`s as well as `TokenTree`s and `TokenStream`s (fixes#39746), and
- to preserve syntactic space, requires that `$` be followed by
- a single identifier to unquote, or
- another `$` to produce a literal `$`.
r? @nrc
In recent months there have been a few different people investigating how to make a plugin that
registers a MIR-pass – one that isn’t intended to be eventually merged into rustc proper.
The interface to register MIR passes was added primarily for miri (& later was
found to make prototyping of rustc-proper MIR passes a tiny bit faster). Since miri does not use
this interface anymore it seems like a good time to remove this "feature".
For prototyping purposes a similar interface can be added by developers themselves in their custom
rustc build.
Implement function-like procedural macros ( `#[proc_macro]`)
Adds the `#[proc_macro]` attribute, which expects bare functions of the kind `fn(TokenStream) -> TokenStream`, which can be invoked like `my_macro!()`.
cc rust-lang/rfcs#1913, #38356
r? @jseyfried
cc @nrc
Implement `#[proc_macro_attribute]`
This implements `#[proc_macro_attribute]` as described in https://github.com/rust-lang/rfcs/pull/1566
The following major (hopefully non-breaking) changes are included:
* Refactor `proc_macro::TokenStream` to use `syntax::tokenstream::TokenStream`.
* `proc_macro::tokenstream::TokenStream` no longer emits newlines between items, this can be trivially restored if desired
* `proc_macro::TokenStream::from_str` does not try to parse an item anymore, moved to `impl MultiItemModifier for CustomDerive` with more informative error message
* Implement `#[proc_macro_attribute]`, which expects functions of the kind `fn(TokenStream, TokenStream) -> TokenStream`
* Reactivated `#![feature(proc_macro)]` and gated `#[proc_macro_attribute]` under it
* `#![feature(proc_macro)]` and `#![feature(custom_attribute)]` are mutually exclusive
* adding `#![feature(proc_macro)]` makes the expansion pass assume that any attributes that are not built-in, or introduced by existing syntax extensions, are proc-macro attributes
* Fix `feature_gate::find_lang_feature_issue()` to not use `unwrap()`
* This change wasn't necessary for this PR, but it helped debugging a problem where I was using the wrong feature string.
* Move "completed feature gate checking" pass to after "name resolution" pass
* This was necessary for proper feature-gating of `#[proc_macro_attribute]` invocations when the `proc_macro` feature flag isn't set.
Prototype/Litmus Test: [Implementation](https://github.com/abonander/anterofit/blob/proc_macro/service-attr/src/lib.rs#L13) -- [Usage](https://github.com/abonander/anterofit/blob/proc_macro/service-attr/examples/post_service.rs#L35)
Stop warning when doc testing proc macro crates
Fixes#39064
Add the test option to the session struct that is passed
to phase_2_configure_and_expand function inside the
rustdoc test module.
This prevents the warning code from triggering when
parsing proc_macro_derive attributes, just like when
`--test` is normally invoked.
This change makes the warning disappear, but I'm not sure what else it might change. So this early PR is mainly to run the test suite, and to get feedback.
* Add support for `#[proc_macro]`
* Reactivate `proc_macro` feature and gate `#[proc_macro_attribute]` under it
* Have `#![feature(proc_macro)]` imply `#![feature(use_extern_macros)]`,
error on legacy import of proc macros via `#[macro_use]`
This commit stabilizes the `proc_macro` and `proc_macro_lib` features in the
compiler to stabilize the "Macros 1.1" feature of the language. Many more
details can be found on the tracking issue, #35900.
Closes#35900
Clean up `ast::Attribute`, `ast::CrateConfig`, and string interning
This PR
- removes `ast::Attribute_` (changing `Attribute` from `Spanned<Attribute_>` to a struct),
- moves a `MetaItem`'s name from the `MetaItemKind` variants to a field of `MetaItem`,
- avoids needlessly wrapping `ast::MetaItem` with `P`,
- moves string interning into `syntax::symbol` (`ast::Name` is a reexport of `symbol::Symbol` for now),
- replaces `InternedString` with `Symbol` in the AST, HIR, and various other places, and
- refactors `ast::CrateConfig` from a `Vec` to a `HashSet`.
r? @eddyb
Fix regression involving custom derives on items with `$crate`
The regression was introduced in #37213.
I believe we cannot make the improvements from #37213 work with the current custom derive setup (c.f. https://github.com/rust-lang/rust/issues/37637#issuecomment-258959145) -- we'll have to wait for `TokenStream`'s API to improve.
Fixes#37637.
r? @nrc
macros 1.1: Allow proc_macro functions to declare attributes to be mark as used
This PR allows proc macro functions to declare attribute names that should be marked as used when attached to the deriving item. There are a few questions for this PR.
- Currently this uses a separate attribute named `#[proc_macro_attributes(..)]`, is this the best choice?
- In order to make this work, the `check_attribute` function had to be modified to not error on attributes marked as used. This is a pretty large change in semantics, is there a better way to do this?
- I've got a few clones where I don't know if I need them (like turning `item` into a `TokenStream`), can these be avoided?
- Is switching to `MultiItemDecorator` the right thing here?
Also fixes https://github.com/rust-lang/rust/issues/37563.
