Add `-Z external-clangrt`
This adds the unstable `-Z external-clangrt` flag that will prevent rustc from emitting linker paths for the in-tree LLVM sanitizer runtime library.
coverage: Initial support for branch coverage instrumentation
(This is a review-ready version of the changes that were drafted in #118305.)
This PR adds support for branch coverage instrumentation, gated behind the unstable flag value `-Zcoverage-options=branch`. (Coverage instrumentation must also be enabled with `-Cinstrument-coverage`.)
During THIR-to-MIR lowering (MIR building), if branch coverage is enabled, we collect additional information about branch conditions and their corresponding then/else blocks. We inject special marker statements into those blocks, so that the `InstrumentCoverage` MIR pass can reliably identify them even after the initially-built MIR has been simplified and renumbered.
The rest of the changes are mostly just plumbing needed to gather up the information that was collected during MIR building, and include it in the coverage metadata that we embed in the final binary.
Note that `llvm-cov show` doesn't print branch coverage information in its source views by default; that needs to be explicitly enabled with `--show-branches=count` or similar.
---
The current implementation doesn't have any support for instrumenting `if let` or let-chains. I think it's still useful without that, and adding it would be non-trivial, so I'm happy to leave that for future work.
Make incremental sessions identity no longer depend on the crate names provided by source code
This makes incremental sessions identity no longer depend on the crate names provided by source code, implementing
https://github.com/rust-lang/compiler-team/issues/726.
r? ````@oli-obk````
This adds the unstable `-Z external-sanitizer-runtime` flag that will
prevent rustc from emitting linker paths for the in-tree LLVM sanitizer
runtime library.
coverage: Remove or migrate all unstable values of `-Cinstrument-coverage`
(This PR was substantially overhauled from its original version, which migrated all of the existing unstable values intact.)
This PR takes the three nightly-only values that are currently accepted by `-Cinstrument-coverage`, completely removes two of them (`except-unused-functions` and `except-unused-generics`), and migrates the third (`branch`) over to a newly-introduced unstable flag `-Zcoverage-options`.
I have a few motivations for wanting to do this:
- It's unclear whether anyone actually uses the `except-unused-*` values, so this serves as an opportunity to either remove them, or prompt existing users to object to their removal.
- After #117199, the stable values of `-Cinstrument-coverage` treat it as a boolean-valued flag, so having nightly-only extra values feels out-of-place.
- Nightly-only values also require extra ad-hoc code to make sure they aren't accidentally exposed to stable users.
- The new system allows multiple different settings to be toggled independently, which isn't possible in the current single-value system.
- The new system makes it easier to introduce new behaviour behind an unstable toggle, and then gather nightly-user feedback before possibly making it the default behaviour for all users.
- The new system also gives us a convenient place to put relatively-narrow options that won't ever be the default, but that nightly users might still want access to.
- It's likely that we will eventually want to give stable users more fine-grained control over coverage instrumentation. The new flag serves as a prototype of what that stable UI might eventually look like.
The `branch` option is a placeholder that currently does nothing. It will be used by #122322 to opt into branch coverage instrumentation.
---
I see `-Zcoverage-options` as something that will exist more-or-less indefinitely, though individual sub-options might come and go as appropriate. I think there will always be some demand for nightly-only toggles, so I don't see `-Zcoverage-options` itself ever being stable, though we might eventually stabilize something similar to it.
Verify that query keys result in unique dep nodes
This implements checking that query keys result into unique dep nodes as mentioned in https://github.com/rust-lang/rust/pull/112469.
We could do a perf check to see how expensive this is.
r? `@michaelwoerister`
This new nightly-only flag can be used to toggle fine-grained flags that
control the details of coverage instrumentation.
Currently the only supported flag value is `branch` (or `no-branch`), which is
a placeholder for upcoming support for branch coverage. Other flag values can
be added in the future, to prototype proposed new behaviour, or to enable
special non-default behaviour.
Removing absolute path in proc-macro
With rust 1.75 the absolute build path name is embedding into proc-macro (.rustc section) and which causes reproducibility issues.
Detailed issue description is here - https://github.com/rust-lang/rust/issues/120825#issuecomment-1964307219
With this change the 'absolute path' changed back to '/rust/$hash' format as in earlier revisions.
Rework `untranslatable_diagnostic` lint
Currently it only checks calls to functions marked with `#[rustc_lint_diagnostics]`. This PR changes it to check calls to any function with an `impl Into<{D,Subd}iagnosticMessage>` parameter. This greatly improves its coverage and doesn't rely on people remembering to add `#[rustc_lint_diagnostics]`. It also lets us add `#[rustc_lint_diagnostics]` to a number of functions that don't have an `impl Into<{D,Subd}iagnosticMessage>`, such as `Diag::span`.
r? ``@davidtwco``
Prior to the previous commit, `#[rust_lint_diagnostics]` attributes
could only be used on methods with an `impl Into<{D,Subd}iagMessage>`
parameter. But there are many other nearby diagnostic methods (e.g.
`Diag::span`) that don't take such a parameter and should have the
attribute.
This commit adds the missing attribute to these `Diag` methods. This
requires adding some missing
`#[allow(rustc::diagnostic_outside_of_impl)]` markers at call sites to
these methods.
Currently it only checks calls to functions marked with
`#[rustc_lint_diagnostics]`. This commit changes it to check calls to
any function with an `impl Into<{D,Subd}iagMessage>` parameter. This
greatly improves its coverage and doesn't rely on people remembering to
add `#[rustc_lint_diagnostics]`.
The commit also adds `#[allow(rustc::untranslatable_diagnostic)`]
attributes to places that need it that are caught by the improved lint.
These places that might be easy to convert to translatable diagnostics.
Finally, it also:
- Expands and corrects some comments.
- Does some minor formatting improvements.
- Adds missing `DecorateLint` cases to
`tests/ui-fulldeps/internal-lints/diagnostics.rs`.
errors: share `SilentEmitter` between rustc and rustfmt
Fixesrust-lang/rustfmt#6082.
Shares the `SilentEmitter` between rustc and rustfmt, and gives it a fallback bundle (since it can emit diagnostics in some contexts).
Existing names for values of this type are `sess`, `parse_sess`,
`parse_session`, and `ps`. `sess` is particularly annoying because
that's also used for `Session` values, which are often co-located, and
it can be difficult to know which type a value named `sess` refers to.
(That annoyance is the main motivation for this change.) `psess` is nice
and short, which is good for a name used this much.
The commit also renames some `parse_sess_created` values as
`psess_created`.
With rust 1.75 the absolute build path is embedding into '.rustc' section and which causes reproducibility issues. Detailed issue is here.
https://github.com/rust-lang/rust/issues/120825#issuecomment-1964307219
With this change the 'absolute path' changed back to '/rust/$hash' format.
Adds initial support for DataFlowSanitizer to the Rust compiler. It
currently supports `-Zsanitizer-dataflow-abilist`. Additional options
for it can be passed to LLVM command line argument processor via LLVM
arguments using `llvm-args` codegen option (e.g.,
`-Cllvm-args=-dfsan-combine-pointer-labels-on-load=false`).
Emitter cleanups
Some cleanups I made when reading emitter code. In particular, `HumanEmitter` and `JsonEmitter` have gone from three constructors to one.
r? `@oli-obk`
Stashed errors used to be counted as errors, but could then be
cancelled, leading to `ErrorGuaranteed` soundness holes. #120828 changed
that, closing the soundness hole. But it introduced other difficulties
because you sometimes have to account for pending stashed errors when
making decisions about whether errors have occured/will occur and it's
easy to overlook these.
This commit aims for a middle ground.
- Stashed errors (not warnings) are counted immediately as emitted
errors, avoiding the possibility of forgetting to consider them.
- The ability to cancel (or downgrade) stashed errors is eliminated, by
disallowing the use of `steal_diagnostic` with errors, and introducing
the more restrictive methods `try_steal_{modify,replace}_and_emit_err`
that can be used instead.
Other things:
- `DiagnosticBuilder::stash` and `DiagCtxt::stash_diagnostic` now both
return `Option<ErrorGuaranteed>`, which enables the removal of two
`delayed_bug` calls and one `Ty::new_error_with_message` call. This is
possible because we store error guarantees in
`DiagCtxt::stashed_diagnostics`.
- Storing the guarantees also saves us having to maintain a counter.
- Calls to the `stashed_err_count` method are no longer necessary
alongside calls to `has_errors`, which is a nice simplification, and
eliminates two more `span_delayed_bug` calls and one FIXME comment.
- Tests are added for three of the four fixed PRs mentioned below.
- `issue-121108.rs`'s output improved slightly, omitting a non-useful
error message.
Fixes#121451.
Fixes#121477.
Fixes#121504.
Fixes#121508.
PR #119097 made the decision to make all `IntoDiagnostic` impls generic,
because this allowed a bunch of nice cleanups. But four hand-written
impls were unintentionally overlooked. This commit makes them generic.
Currently `emit_stashed_diagnostic` is called from four(!) different
places: `print_error_count`, `DiagCtxtInner::drop`, `abort_if_errors`,
and `compile_status`.
And `flush_delayed` is called from two different places:
`DiagCtxtInner::drop` and `Queries`.
This is pretty gross! Each one should really be called from a single
place, but there's a bunch of entanglements. This commit cleans up this
mess.
Specifically, it:
- Removes all the existing calls to `emit_stashed_diagnostic`, and adds
a single new call in `finish_diagnostics`.
- Removes the early `flush_delayed` call in `codegen_and_build_linker`,
replacing it with a simple early return if delayed bugs are present.
- Changes `DiagCtxtInner::drop` and `DiagCtxtInner::flush_delayed` so
they both assert that the stashed diagnostics are empty (i.e.
processed beforehand).
- Changes `interface::run_compiler` so that any errors emitted during
`finish_diagnostics` (i.e. late-emitted stashed diagnostics) are
counted and cannot be overlooked. This requires adding
`ErrorGuaranteed` return values to several functions.
- Removes the `stashed_err_count` call in `analysis`. This is possible
now that we don't have to worry about calling `flush_delayed` early
from `codegen_and_build_linker` when stashed diagnostics are pending.
- Changes the `span_bug` case in `handle_tuple_field_pattern_match` to a
`delayed_span_bug`, because it now can be reached due to the removal
of the `stashed_err_count` call in `analysis`.
- Slightly changes the expected output of three tests. If no errors are
emitted but there are delayed bugs, the error count is no longer
printed. This is because delayed bugs are now always printed after the
error count is printed (or not printed, if the error count is zero).
There is a lot going on in this commit. It's hard to break into smaller
pieces because the existing code is very tangled. It took me a long time
and a lot of effort to understand how the different pieces interact, and
I think the new code is a lot simpler and easier to understand.
Currently `has_errors` excludes lint errors. This commit changes it to
include lint errors.
The motivation for this is that for most places it doesn't matter
whether lint errors are included or not. But there are multiple places
where they must be includes, and only one place where they must not be
included. So it makes sense for `has_errors` to do the thing that fits
the most situations, and the new `has_errors_excluding_lint_errors`
method in the one exceptional place.
The same change is made for `err_count`. Annoyingly, this requires the
introduction of `err_count_excluding_lint_errs` for one place, to
preserve existing error printing behaviour. But I still think the change
is worthwhile overall.
Overhaul `Diagnostic` and `DiagnosticBuilder`
Implements the first part of https://github.com/rust-lang/compiler-team/issues/722, which moves functionality and use away from `Diagnostic`, onto `DiagnosticBuilder`.
Likely follow-ups:
- Move things around, because this PR was written to minimize diff size, so some things end up in sub-optimal places. E.g. `DiagnosticBuilder` has impls in both `diagnostic.rs` and `diagnostic_builder.rs`.
- Rename `Diagnostic` as `DiagInner` and `DiagnosticBuilder` as `Diag`.
r? `@davidtwco`
Currently many diagnostic modifier methods are available on both
`Diagnostic` and `DiagnosticBuilder`. This commit removes most of them
from `Diagnostic`. To minimize the diff size, it keeps them within
`diagnostic.rs` but changes the surrounding `impl Diagnostic` block to
`impl DiagnosticBuilder`. (I intend to move things around later, to give
a more sensible code layout.)
`Diagnostic` keeps a few methods that it still needs, like `sub`,
`arg`, and `replace_args`.
The `forward!` macro, which defined two additional methods per call
(e.g. `note` and `with_note`), is replaced by the `with_fn!` macro,
which defines one additional method per call (e.g. `with_note`). It's
now also only used when necessary -- not all modifier methods currently
need a `with_*` form. (New ones can be easily added as necessary.)
All this also requires changing `trait AddToDiagnostic` so its methods
take `DiagnosticBuilder` instead of `Diagnostic`, which leads to many
mechanical changes. `SubdiagnosticMessageOp` gains a type parameter `G`.
There are three subdiagnostics -- `DelayedAtWithoutNewline`,
`DelayedAtWithNewline`, and `InvalidFlushedDelayedDiagnosticLevel` --
that are created within the diagnostics machinery and appended to
external diagnostics. These are handled at the `Diagnostic` level, which
means it's now hard to construct them via `derive(Diagnostic)`, so
instead we construct them by hand. This has no effect on what they look
like when printed.
There are lots of new `allow` markers for `untranslatable_diagnostics`
and `diagnostics_outside_of_impl`. This is because
`#[rustc_lint_diagnostics]` annotations were present on the `Diagnostic`
modifier methods, but missing from the `DiagnosticBuilder` modifier
methods. They're now present.
There are lots of functions that modify a diagnostic. This can be via a
`&mut Diagnostic` or a `&mut DiagnosticBuilder`, because the latter type
wraps the former and impls `DerefMut`.
This commit converts all the `&mut Diagnostic` occurrences to `&mut
DiagnosticBuilder`. This is a step towards greatly simplifying
`Diagnostic`. Some of the relevant function are made generic, because
they deal with both errors and warnings. No function bodies are changed,
because all the modifier methods are available on both `Diagnostic` and
`DiagnosticBuilder`.
