rust/compiler/rustc_typeck
bors dff1edf919 Auto merge of #79519 - cjgillot:noattr, r=wesleywiser
Store HIR attributes in a side table

Same idea as #72015 but for attributes.
The objective is to reduce incr-comp invalidations due to modified attributes.
Notably, those due to modified doc comments.

Implementation:
- collect attributes during AST->HIR lowering, in `LocalDefId -> ItemLocalId -> &[Attributes]` nested tables;
- access the attributes through a `hir_owner_attrs` query;
- local refactorings to use this access;
- remove `attrs` from HIR data structures one-by-one.

Change in behaviour:
- the HIR visitor traverses all attributes at once instead of parent-by-parent;
- attribute arrays are sometimes duplicated: for statements and variant constructors;
- as a consequence, attributes are marked as used after unused-attribute lint emission to avoid duplicate lints.

~~Current bug: the lint level is not correctly applied in `std::backtrace_rs`, triggering an unused attribute warning on `#![no_std]`. I welcome suggestions.~~
2021-03-10 08:40:51 +00:00
..
src Auto merge of #79519 - cjgillot:noattr, r=wesleywiser 2021-03-10 08:40:51 +00:00
Cargo.toml bumped smallvec deps 2021-02-14 18:03:11 +03:00
README.md

For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.