Backend and target selection is a mess: the target can override the
backend (via `Target::default_codegen_backend`), *and* the backend can
override the target (via `CodegenBackend::target_override`).
The code that handles this is ugly. It calls `build_target_config`
twice, once before getting the backend and once again afterward. It also
must check that both overrides aren't triggering at the same time.
This commit removes the latter override. It's used in rust-gpu but
@eddyb said via Zulip that removing it would be ok. This simplifies the
code greatly, and will allow some nice follow-up refactorings.
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.
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`).
bjorn3 says:
> On errors we don't finalize the incr comp cache, but non-fatal diagnostics are cached afaik.
Otherwise we would have to replay the query in question, which we may not be able to do if the query
key is not reconstructible from the dep node fingerprint.
So we must track these flags to avoid replaying incorrect diagnostics.
It was added in #54232. It seems like it was aimed at NLL development,
which is well in the past. Also, it looks like `-Ztreat-err-as-bug` can
be used to achieve the same effect. So it doesn't seem necessary.
Remove `-Zreport-delayed-bugs`.
It's not used within the repository in any way (e.g. in tests), and doesn't seem useful.
It was added in #52568.
r? ````@oli-obk````
Remove `-Zdump-mir-spanview`
The `-Zdump-mir-spanview` flag was added back in #76074, as a development/debugging aid for the initial work on what would eventually become `-Cinstrument-coverage`. It causes the compiler to emit an HTML file containing a function's source code, with various spans highlighted based on the contents of MIR.
When the suggestion was made to [triage and remove unnecessary `-Z` flags (Zulip)](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/.60-Z.60.20option.20triage), I noted that this flag could potentially be worth removing, but I wanted to keep it around to see whether I found it useful for my own coverage work.
But when I actually tried to use it, I ran into various issues (e.g. it crashes on `tests/coverage/closure.rs`). If I can't trust it to work properly without a full overhaul, then instead of diving down a rabbit hole of trying to fix arcane span-handling bugs, it seems better to just remove this obscure old code entirely.
---
````@rustbot```` label +A-code-coverage
`build_session` is passed an `EarlyErrorHandler` and then constructs a
`Handler`. But the `EarlyErrorHandler` is still used for some time after
that.
This commit changes `build_session` so it consumes the passed
`EarlyErrorHandler`, and also drops it as soon as the `Handler` is
built. As a result, `parse_cfg` and `parse_check_cfg` now take a
`Handler` instead of an `EarlyErrorHandler`.
This is intended to be used for Linux kernel RETHUNK builds.
With this commit (optionally backported to Rust 1.73.0), plus a
patched Linux kernel to pass the flag, I get a RETHUNK build with
Rust enabled that is `objtool`-warning-free and is able to boot in
QEMU and load a sample Rust kernel module.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Add -Z llvm_module_flag
Allow adding values to the `!llvm.module.flags` metadata for a generated module. The syntax is
`-Z llvm_module_flag=<name>:<type>:<value>:<behavior>`
Currently only u32 values are supported but the type is required to be specified for forward compatibility. The `behavior` element must match one of the named LLVM metadata behaviors.viors.
This flag is expected to be perma-unstable.
Remove `-Zperf-stats`.
The included measurements have varied over the years. At one point there were quite a few more, but #49558 deleted a lot that were no longer used. Today there's just four, and it's a motley collection that doesn't seem particularly valuable.
I think it has been well and truly subsumed by self-profiling, which collects way more data.
r? `@wesleywiser`
The included measurements have varied over the years. At one point there
were quite a few more, but #49558 deleted a lot that were no longer
used. Today there's just four, and it's a motley collection that doesn't
seem particularly valuable.
I think it has been well and truly subsumed by self-profiling, which
collects way more data.
Allow adding values to the `!llvm.module.flags` metadata for a generated
module. The syntax is
`-Z llvm_module_flag=<name>:<type>:<value>:<behavior>`
Currently only u32 values are supported but the type is required to be
specified for forward compatibility. The `behavior` element must match
one of the named LLVM metadata behaviors.viors.
This flag is expected to be perma-unstable.
It was added way back in #28585 under the name `-Zkeep-mtwt-tables`. The
justification was:
> This is so that the resolution results can be used after analysis,
> potentially for tool support.
There are no uses of significance in the code base, and various Google
searches for both option names (and variants) found nothing of interest.
@petrochenkov says removing this part (and it's only part) of the
hygiene data is dubious. It doesn't seem that big, so let's just keep it
around.
`parse_cfgspecs` and `parse_check_cfg` run very early, before the main
interner is running. They each use a short-lived interner and convert
all interned symbols to strings in their output data structures. Once
the main interner starts up, these data structures get converted into
new data structures that are identical except with the strings converted
to symbols.
All is not obvious from the current code, which is a mess, particularly
with inconsistent naming that obscures the parallel string/symbol data
structures. This commit clean things up a lot.
- The existing `CheckCfg` type is generic, allowing both
`CheckCfg<String>` and `CheckCfg<Symbol>` forms. This is really
useful, but it defaults to `String`. The commit removes the default so
we have to use `CheckCfg<String>` and `CheckCfg<Symbol>` explicitly,
which makes things clearer.
- Introduces `Cfg`, which is generic over `String` and `Symbol`, similar
to `CheckCfg`.
- Renames some things.
- `parse_cfgspecs` -> `parse_cfg`
- `CfgSpecs` -> `Cfg<String>`, plus it's used in more places, rather
than the underlying `FxHashSet` type.
- `CrateConfig` -> `Cfg<Symbol>`.
- `CrateCheckConfig` -> `CheckCfg<Symbol>`
- Adds some comments explaining the string-to-symbol conversions.
- `to_crate_check_config`, which converts `CheckCfg<String>` to
`CheckCfg<Symbol>`, is inlined and removed and combined with the
overly-general `CheckCfg::map_data` to produce
`CheckCfg::<String>::intern`.
- `build_configuration` now does the `Cfg<String>`-to-`Cfg<Symbol>`
conversion, so callers don't need to, which removes the need for
`to_crate_config`.
The diff for two of the fields in `Config` is a good example of the
improved clarity:
```
- pub crate_cfg: FxHashSet<(String, Option<String>)>,
- pub crate_check_cfg: CheckCfg,
+ pub crate_cfg: Cfg<String>,
+ pub crate_check_cfg: CheckCfg<String>,
```
Compare that with the diff for the corresponding fields in `ParseSess`,
and the relationship to `Config` is much clearer than before:
```
- pub config: CrateConfig,
- pub check_config: CrateCheckConfig,
+ pub config: Cfg<Symbol>,
+ pub check_config: CheckCfg<Symbol>,
```
In `test_edition_parsing`, change the
`build_session_options_and_crate_config` call to
`build_session_options`, because the config isn't used.
That leaves a single call site for
`build_session_options_and_crate_config`, so just inline and remove it.
The value of `-Cinstrument-coverage=` doesn't need to be `Option`
(Extracted from #117199, since this is a purely internal cleanup that can land independently.)
Not using this flag is identical to passing `-Cinstrument-coverage=off`, so there's no need to distinguish between `None` and `Some(Off)`.
Stop telling people to submit bugs for internal feature ICEs
This keeps track of usage of internal features, and changes the message to instead tell them that using internal features is not supported.
I thought about several ways to do this but now used the explicit threading of an `Arc<AtomicBool>` through `Session`. This is not exactly incremental-safe, but this is fine, as this is set during macro expansion, which is pre-incremental, and also only affects the output of ICEs, at which point incremental correctness doesn't matter much anyways.
See [MCP 620.](https://github.com/rust-lang/compiler-team/issues/596)
