Now that region::Scope is no longer interned, its size is more
important. This PR encodes region::Scope in 8 bytes instead of 12, which
should speed up region inference somewhat (perf testing needed) and
should improve the margins on #36799 by 64MB (that's not a lot, I did
this PR mostly to speed up region inference).
This wraps unsizing coercions within an additional level of
`commit_if_ok`, which rolls back type variables if the unsizing coercion
fails. This prevents a large amount of type-variables from accumulating
while type-checking a large function, e.g. shaving 2GB off one of the
4GB peaks in #36799.
incr.comp.: Add new DepGraph implementation.
This commits does a few things:
1. It adds the new dep-graph implementation -- *in addition* to the old one. This way we can start testing the new implementation without switching all tests at once.
2. It persists the new dep-graph (which includes query result fingerprints) to the incr. comp. caching directory and also loads this data.
3. It removes support for loading fingerprints of metadata imported from other crates (except for when running autotests). This is not needed anymore with red/green. It could provide a performance advantage but that's yet to be determined. For now, as red/green is not fully implemented yet, the cross-crate incremental tests are disabled.
Note, this PR is based on top of soon-to-be-merged #44696 and only the last 4 commits are new:
```
- incr.comp.: Initial implemenation of append-only dep-graph. (c90147c)
- incr.comp.: Do some various cleanup. (8ce20c5)
- incr.comp.: Serialize and deserialize new DepGraph. (0e13c1a)
- incr.comp.: Remove support for loading metadata fingerprints. (270a134)
EDIT 2:
- incr.comp.: Make #[rustc_dirty/clean] test for fingerprint equality ... (d8f7ff9)
```
(EDIT: GH displays the commits in the wrong order for some reason)
Also note that this PR is expected to certainly result in performance regressions in the incr. comp. test cases, since we are adding quite a few things (a whole additional dep-graph, for example) without removing anything. End-to-end performance measurements will only make sense again after red/green is enabled and all the legacy tracking has been turned off.
EDIT 2: Pushed another commit that makes the `#[rustc_dirty]`/`#[rustc_clean]` based autotests compared query result fingerprints instead of testing `DepNode` existence.
Record semantic types for all syntactic types in bodies
... and use recorded types in type privacy checking (types are recorded after inference, so there are no `_`s left).
Also use `hir_ty_to_ty` for types in signatures in type privacy checking.
This could also be potentially useful for save-analysis and diagnostics.
Fixes https://github.com/rust-lang/rust/pull/42125#issuecomment-305987755
r? @eddyb
std::sync::RwLock docs improvement
Addresses the `RwLock` part of #29377.
r? @steveklabnik
Added examples, links to types, and a small comparison between RwLock and Mutex.
Less confusing placeholder when RefCell is exclusively borrowed
Based on ExpHP's comment in [*RefCell.borrow_mut get strange result*](https://users.rust-lang.org/t/refcell-borrow-mut-get-strange-result/12994):
> it would perhaps be nicer if it didn't put something that could be misinterpreted as a valid string value
The previous Debug implementation would show:
RefCell { value: "<borrowed>" }
The new one is:
RefCell { value: <borrowed> }
rustc: Don't use DelimToken::None if possible
This commit fixes a regression from #44601 where lowering attribute to HIR now
involves expanding interpolated tokens to their actual tokens. In that commit
all interpolated tokens were surrounded with a `DelimToken::None` group of
tokens, but this ended up causing regressions like #44730 where the various
attribute parsers in `syntax/attr.rs` weren't ready to cope with
`DelimToken::None`. Instead of fixing the parser in `attr.rs` this commit
instead opts to just avoid the `DelimToken::None` in the first place, ensuring
that the token stream should look the same as it did before where possible.
Closes#44730
Make `-Z borrowck-mir` imply that `EndRegion`'s should be emitted.
Before this change, the `-Z borrowck-mir` flag is useless if you do not also pass `-Z emit-end-regions`.
So, in the same spirit as f2892ad281, make `-Z borrowck-mir` also emit `EndRegion` statements. (This will hopefully avoid some initial speed bumps for new-comers helping out with NLL.)
fix an incorrect assertion in the doc example for `std::io::copy`
I think this wasn't caught by CI because the `foo` wrapper function was only defined and not called. This seems to be the norm for doc examples that define a `foo` function. Is that on purpose?
Expand size_of docs
This PR does 3 things.
1. Adds a description of what pointer size means to the primitive pages for usize and isize.
2. Says the general size of things is not stable from compiler to compiler.
3. Adds a table of sizes of things that we do guarantee. As this is the first table in the libstd docs, I've included a picture of how that looks.
only set non-ADT derive error once per attribute, not per trait
I found the expansion code very hard to follow, leaving me unsure as to whether this might somehow be done better, but this patch does give us the behavior requested in #43927 (up to exact choice of span; here, it's the entire attribute, not just the `derive` token).
(Note to GitHub robots: _resolves #43927_.)
r? @jseyfried
incr.comp.: Move task result fingerprinting into DepGraph.
This PR
- makes the DepGraph store all `Fingerprints` of task results,
- allows `DepNode` to be marked as input nodes,
- makes HIR node hashing use the regular fingerprinting infrastructure,
- removes the now unused `IncrementalHashesMap`, and
- makes sure that `traits_in_scope_map` fingerprints are stable.
r? @nikomatsakis
cc @alexcrichton
Retain suid/sgid/sticky bits in Metadata.permissions
Most users would expect set_permissions(Metadata.permissions()) to be
non-destructive. While we can't guarantee this, we can at least pass
the needed info to chmod.
Also update the PermissionsExt documentation to disambiguate what it
contains, and to refer to the underlying value as `st_mode` rather than
its type `mode_t`.
Closes#44147
Catch IOError in bootstrap.py when loading config.toml
When I pulled this repo and tried to build using the command in the readme, I got an error about a missing `config.toml`.
If config.toml doesn't exist, then an `IOError` will be raised the `with open(...)` line. Prior to e788fa7b6c, this was caught because the `except` clause didn't specify what exceptions it caught, so both `IOError` and `OSError` were caught.
First time contributing, so please let me know if I'm doing anything wrong.
Based on ExpHP's comment in
https://users.rust-lang.org/t/refcell-borrow-mut-get-strange-result/12994
> it would perhaps be nicer if it didn't put something that could be
> misinterpreted as a valid string value
The previous Debug implementation would show:
RefCell { value: "<borrowed>" }
The new one is:
RefCell { value: <borrowed> }
A slight eccentricity of this change is that now non-ADT-derive errors prevent
derive-macro-not-found errors from surfacing (see changes to the
gating-of-derive compile-fail tests).
Resolves#43927.
