It encapsulate the (part of) the interface between the parser and
macro by example (macro_rules) parser.
The second bit is somewhat more general `parse_ast_fragment`, which is
the reason why we keep some `parse_xxx` functions as public.
[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
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
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>
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
Improve diagnostics when constant pattern is too generic
This PR is a follow-up to PR #74538 and issue #73976
When constants queries Layout, TypeId or type_name of a generic parameter, instead of emitting `could not evaluate constant pattern`, we will instead emit a more detailed message `constant pattern depends on a generic parameter`.
rustc: Ignore fs::canonicalize errors in metadata
This commit updates the metadata location logic to ignore errors when
calling `fs::canonicalize`. Canonicalization was added historically so
multiple `-L` paths to the same directory don't print errors about
multiple candidates (since rustc can deduplicate same-named paths), but
canonicalization doesn't work on all filesystems. Cargo, for example,
always uses this sort of fallback where it will opportunitistically try
to canonicalize but fall back to using the input path if it otherwise
doesn't work.
If rustc is run on a filesystem that doesn't support canonicalization
then the effect of this change will be that `-L` paths which logically
point to the same directory will cause errors, but that's a rare enough
occurrence it shouldn't cause much issue in practice. Otherwise rustc
doesn't work at all today on those sorts of filesystem where
canonicalization isn't supported!
Enable docs on dist-x86_64-musl
Add the `rust-docs` component to toolchain `x86_64-unknown-linux-musl`, which allows people using rustup on their musl-based linux distribution to download the rust-docs.
`--disable-docs` is based on the assumption that `x86_64-unknown-linux-musl` is only a cross-compile target.
I have tested that the docs are built. I assume the build-system will automatically detect the docs and create a `rust-docs` component. I will [monitor](https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-musl.html) the components and create a follow-up PR, if the docs aren't published.
See also #70619, where we enabled `rust-lld` to enable the wasm-workflow on musl-based linux distributions.
Fixed 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.
This commit updates the metadata location logic to ignore errors when
calling `fs::canonicalize`. Canonicalization was added historically so
multiple `-L` paths to the same directory don't print errors about
multiple candidates (since rustc can deduplicate same-named paths), but
canonicalization doesn't work on all filesystems. Cargo, for example,
always uses this sort of fallback where it will opportunitistically try
to canonicalize but fall back to using the input path if it otherwise
doesn't work.
If rustc is run on a filesystem that doesn't support canonicalization
then the effect of this change will be that `-L` paths which logically
point to the same directory will cause errors, but that's a rare enough
occurrence it shouldn't cause much issue in practice. Otherwise rustc
doesn't work at all today on those sorts of filesystem where
canonicalization isn't supported!
Fix incorrect clashing_extern_declarations warnings.
Fixes#73735, fixes#73872.
Fix clashing_extern_declarations warning for `#[repr(transparent)]` structs and safely-FFI-convertible enums, and not warning for clashes of struct members of different types, but the same size.
r? @nagisa
Aleksey Kladov
