[mir] Special treatment for dereferencing a borrow to a static definition
Fix#70584.
As suggested by @oli-obk in this [comment](https://github.com/rust-lang/rust/issues/70584#issuecomment-626009260), one can chase the definition of the local variable being de-referenced and check if it is a true static variable. If that is the case, `validate_place` will admit the promotion.
This is my first time to contribute to `rustc`, and I have two questions.
1. A generalization to some extent is applied to decide if the promotion is possible in the static context. In case that there are more projection operations preceding the de-referencing, `validate_place` recursively decent into inner projection operations. I have put thoughts into its correctness but I am not totally sure about it.
2. I have a hard time to find a good place for the test case. This patch has to do with MIR, but this test case would look out of place compared to other tests in `src/test/ui/mir` or `src/test/ui/borrowck` because it does not generate errors while others do. It is tentatively placed in `src/test/ui/statics` for now.
Thank you for any comments and suggestions!
mir: add `used_generic_parameters_needs_subst`
Fixes#74636.
This PR adds a `used_generic_parameters_needs_subst` helper function which checks whether a type needs substitution, but only for parameters that the `unused_generic_params` query considers used. This is used in the MIR interpreter to make the check for some pointer casts and for reflection intrinsics more precise.
I've opened this as a draft PR because this might not be the approach we want to fix this issue and we have to decide what to do about the reflection case.
r? @eddyb
cc @lcnr @wesleywiser
Rollup of 6 pull requests
Successful merges:
- #74644 (Remove `linked_list_extras` methods.)
- #74968 (Run all tests if have no specified tests)
- #74982 (1.45.2 release notes)
- #74984 (Miri: fix ICE when unwinding past topmost stack frame)
- #74986 (fix part of comparison that would always evaluate to "true", probably an oversight)
- #74991 (Fix Const-Generic Cycle ICE #74199)
Failed merges:
r? @ghost
Changes:
````
Use the same index location on nightly as beta
relax deprecated diagnostic message check
Don't print to raw stderr in test
Emit the `test` field in cargo metadata
````
Among other things, this brings in [the `__main_argc_argv`] patch,
which simplifies the interaction between the compiler and WASI libc's
startup code, which will help work on reactor support.
[the `__main_argc_argv` patch]: 00072c08c7
Fix Const-Generic Cycle ICE #74199
This PR intends to fix the bug in Issue #74199 by following the suggestion provided of ignoring the error that causes the ICE.
This does not fix the underlying cycle detection issue, but fixes the ICE.
Also adds a test to check that it doesn't causes an ICE but returns a valid error for now.
r? @lcnr
Edit: Also it's funny how this PR number is an anagram of the issue number
* Deduplicate type ascription LHS errors
* Remove duplicated `:` -> `::` suggestion from parse error
* Tweak wording to be more accurate
* Modify `current_type_ascription` to reduce span wrangling
* remove now unnecessary match arm
* Add run-rustfix to appropriate tests
Normalize all opaque types when converting ParamEnv to Reveal::All
When we normalize a type using a ParamEnv with a reveal mode of
RevealMode::All, we will normalize opaque types to their underlying
types (e.g. `type MyOpaque = impl Foo` -> `StructThatImplsFoo`).
However, the ParamEnv may still have predicates referring to the
un-normalized opaque type (e.g. `<T as MyTrait<MyOpaque>>`). This can
cause trait projection to fail, since a type containing normalized
opaque types will not match up with the un-normalized type in the
`ParamEnv`.
To fix this, we now explicitly normalize all opaque types in
caller_bounds of a `ParamEnv` when changing its mode to
`RevealMode::All`. This ensures that all predicatse will refer to the
underlying types of any opaque types involved, allowing them to be
matched up properly during projection. To reflect the fact that
normalization is occuring, `ParamEnv::with_reveal_all` is renamed to
`ParamEnv::with_reveal_all_normalized`
Fixes#65918
This commit adds a `ensure_monomorphic_enough` utility function which
checks whether a type needs substitution, but only for parameters
that the `unused_generic_params` query considers used.
`ensure_monomorphic_enough` is then used throughout interpret where
`needs_subst` checks previously existed (in particular, for some
pointer casts and for reflection intrinsics more precise).
Signed-off-by: David Wood <david@davidtw.co>
Previously `std::fs::File::metadata` on wasm32-wasi would call `fd_filestat_get`
to get metadata associated with fd, but that fd is opened without
RIGHTS_FD_FILESTAT_GET right, so it will failed on correctly implemented WASI
environment.
This change instead to add the missing rights when opening an fd.
Make `Option::unwrap` unstably const
This is lumped into the `const_option` feature gate (#67441), which enables a potpourri of `Option` methods.
cc @rust-lang/wg-const-eval
r? @oli-obk
Rust function-level coverage now works on external crates
Follow-up to a known issue discussed (post-merge) in #74733:
Resolves a known issue in the coverage map where some regions had nonsensical source code locations.
External crate functions are already included in their own coverage maps, per library, and don't need to also
be added to the importing crate's coverage map. (In fact, their source start and end byte positions are not relevant to the importing crate's SourceMap.)
The fix was to simply skip trying to add imported coverage info to the coverage map if the instrumented function is not "local".
The injected counters are still relevant, however, and the LLVM `instrprof.increment` intrinsic call parameters will map those counters to the external crates' coverage maps, when generating runtime coverage data.
Now Rust Coverage can cleanly instrument and analyze coverage on an entire crate and its dependencies.
Example (instrumenting https://github.com/google/json5format):
```bash
$ ./x.py build rust-demangler # make sure the demangler is built
$ cd ~/json5format
$ RUSTC=$HOME/rust/build/x86_64-unknown-linux-gnu/stage1/bin/rustc \
RUSTFLAGS="-Zinstrument-coverage" \
cargo build --example formatjson5
$ LLVM_PROFILE_FILE="formatjson5.profraw" \
./target/debug/examples/formatjson5 session_manager.cml
$ ~/rust/build/x86_64-unknown-linux-gnu/llvm/bin/llvm-profdata merge \
-sparse formatjson5.profraw -o formatjson5.profdata
$ ~/rust/build/x86_64-unknown-linux-gnu/llvm/bin/llvm-cov show --use-color \
--instr-profile=formatjson5.profdata target/debug/examples/formatjson5 \
--show-line-counts-or-regions \
--Xdemangler=$HOME/rust/build/x86_64-unknown-linux-gnu/stage0-tools-bin/rust-demangler \
--show-instantiations \
2>&1 | less -R
```
(Scan forward for some of the non-zero coverage results, with `/^....[0-9]\| *[^ |0]`.)
<img width="1071" alt="Screen Shot 2020-07-30 at 1 21 01 PM" src="https://user-images.githubusercontent.com/3827298/88970627-97e43000-d267-11ea-8e4d-fe40a091f756.png">
Add `--output-format json` for Rustdoc on nightly
This enables the previously deprecated `--output-format` flag so it can be used on nightly to host the experimental implementation of [rfc/2963](https://github.com/rust-lang/rfcs/pull/2963). The actual implementation will come in later PRs so for now there's just a stub that gives you an ICE.
I'm _pretty_ sure that the logic I added makes it inaccessible from stable, but someone should double check that. @tmandry @jyn514
bors
Matthias Krüger
Dan Gohman
Yuki Okushi
Valentin Lazureanu
Bastian Kauschke
kadmin
Oliver Scherer
Ralf Jung
Esteban Küber
Charles Lew
Mark Rousskov
David Wood
Takayuki Nakata
Guillaume Gomez
Ding Xiang Fei
Shen-Ta Hsieh
Lzu Tao
