rust/compiler/rustc_resolve
Aaron Hill ddd544856e
Compute a better lint_node_id during expansion
When we need to emit a lint at a macro invocation, we currently use the
`NodeId` of its parent definition (e.g. the enclosing function). This
means that any `#[allow]` / `#[deny]` attributes placed 'closer' to the
macro (e.g. on an enclosing block or statement) will have no effect.

This commit computes a better `lint_node_id` in `InvocationCollector`.
When we visit/flat_map an AST node, we assign it a `NodeId` (earlier
than we normally would), and store than `NodeId` in current
`ExpansionData`. When we collect a macro invocation, the current
`lint_node_id` gets cloned along with our `ExpansionData`, allowing it
to be used if we need to emit a lint later on.

This improves the handling of `#[allow]` / `#[deny]` for
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` and some `asm!`-related lints.
The 'legacy derive helpers' lint retains its current behavior
(I've inlined the now-removed `lint_node_id` function), since
there isn't an `ExpansionData` readily available.
2021-07-17 23:03:56 -05:00
..
src Compute a better lint_node_id during expansion 2021-07-17 23:03:56 -05:00
Cargo.toml