Instead just use `pprust::path_to_string(..)` where needed.
This has two benefits:
a) The AST definition is now independent of printing it.
(Therefore we get closer to extracting a data-crate.)
b) Debugging should be easier as program flow is clearer.
Refactor librustc_errors::Handler API
This should be reviewed by-commit.
The last commit moves all fields into an inner struct behind a single lock; this is done to prevent possible deadlocks in a multi-threaded compiler, as well as inconsistent state observation.
Document From trait for LhsExpr in parser
Add doc for From trait for converting P<Expr> and Option<ThinVec<Attribute>> to LhsExpr
As part of issue rust-lang#51430 (cc @skade).
Both of these should just be moving an address and setting a discriminant in an enum. The main thing I'm not sure about is whether it's worth documenting the branch in the From<Option<ThinVec<Attribute>>. As far as I can tell it doesn't seem like it is optimized away (although if the discriminant happened to work out you could just copy the pointer and the discriminant which might be cheaper, but that's not guaranteed). So it seems like if it's being called often, it's doubling the number of possible branch mispredictions on this Option, which could be a significant cost.
Let me know if there's anything that needs fixing and I'll get to it as soon as possible!
Bail out when encountering likely missing turbofish in parser
When encountering a likely intended turbofish without `::`, bubble
up the diagnostic instead of emitting it to allow the parser to recover
more gracefully and avoid uneccessary type errors that are likely to be
wrong.
Fix#61329.
When encountering a likely intended turbofish without `::`, bubble
up the diagnostic instead of emitting it to allow the parser to recover
more gracefully and avoid uneccessary type errors that are likely to be
wrong.