Add --Zsave-analysis-api
This is a save-analysis variation which can be used with libraries distributed without their source (e.g., libstd). It will allow IDEs and other tools to get info about types and create URLs to docs and source, without the unnecessary clutter of internal-only save-analysis info. I'm sure we'll iterate somewhat on the design, but this is a first draft.
This is a spiritual succesor to #34268/8531d581, in which we replaced a
number of matches of None to the unit value with `if let` conditionals
where it was judged that this made for clearer/simpler code (as would be
recommended by Manishearth/rust-clippy's `single_match` lint). The same
rationale applies to matches of None to the empty block.
This PR refactors the 'errors' part of libsyntax into its own crate (librustc_errors). This is the first part of a few refactorings to simplify error reporting and potentially support more output formats (like a standardized JSON output and possibly an --explain mode that can work with the user's code), though this PR stands on its own and doesn't assume further changes.
As part of separating out the errors crate, I have also refactored the code position portion of codemap into its own crate (libsyntax_pos). While it's helpful to have the common code positions in a separate crate for the new errors crate, this may also enable further simplifications in the future.
**syntax-[breaking-change]** cc #31645
New `TraitItemKind::Macro` variant
This change adds support for macro expansion inside trait items by adding the new `TraitItemKind::Macro` and associated parsing code.
When items are inlined from extern crates, the filename in the debug info
is taken from the FileMap that's serialized in the rlib metadata.
Currently this is just FileMap.name, which is whatever path is passed to rustc.
Since libcore and libstd are built by invoking rustc with relative paths,
they wind up with relative paths in the rlib, and when linked into a binary
the debug info uses relative paths for the names, but since the compilation
directory for the final binary, tools trying to read source filenames
will wind up with bad paths. We noticed this in Firefox with source
filenames from libcore/libstd having bad paths.
This change stores an absolute path in FileMap.abs_path, and uses that
if available for writing debug info. This is not going to magically make
debuggers able to find the source, but it will at least provide sensible
paths.
save-analysis: be a bit more defensive with field sub-expressions
Prevents an ice with `(...).f` since the sub-expression is in the AST but not the HIR.
We could actually do better in this specific case, but it doesn't seem worth it.
Prevents an ice with `(...).f` since the sub-expression is in the AST but not the HIR.
We could actually do better in this specific case, but it doesn't seem worth it.
save-analysis: use a decoupled representation for dumped data
Closes#33348
This will probably break any tool relying on the csv backend of save_analysis, for the following reasons:
1. Dumped spans don't contain extents anymore (`Dump` uses `SpanData` now instead of internal `Span`s). In case we still want to dump extents we could add them to `SpanData`.
1. `DefId`s are no longer dumped as a pair of `(ref_id, ref_crate)`. Instead, they are dumped as a single `Id`.
@nrc You said something about storing the id in a `u64`, but you didn't explain why. I kept using `u32` in this branch but I can change it if you prefer that.
r? @nrc
By the way, the fact that this breaks tools relying on CSV may be a good occasion to start dumping CSV in a different way (i.e. using the serializer like in the JSON backend).
