Properly re-use def path hash in incremental mode
Fixes#79661
In incremental compilation mode, we update a `DefPathHash -> DefId`
mapping every time we create a `DepNode` for a foreign `DefId`.
This mapping is written out to the on-disk incremental cache, and is
read by the next compilation session to allow us to lazily decode
`DefId`s.
When we decode a `DepNode` from the current incremental cache, we need
to ensure that any previously-recorded `DefPathHash -> DefId` mapping
gets recorded in the new mapping that we write out. However, PR #74967
didn't do this in all cases, leading to us being unable to decode a
`DefPathHash` in certain circumstances.
This PR refactors some of the code around `DepNode` deserialization to
prevent this kind of mistake from happening again.
Also generate `StorageDead` in constants
r? `@eddyb`
None of this special casing is actually necessary since we started promoting within constants and statics.
We may want to keep some of it around out of perf reasons, but it's not required for user visible behaviour
somewhat related: #68622
remove this weird special case from promotion
Promotion has a special case to ignore interior mutability under some specific circumstances. The purpose of this PR is to figure out what changes if we remove that. Since `Cell::new` and friends only get promoted inside `const`/`static` initializers these days, it actually is not easy to exploit this case: you need something like
```rust
const TEST_INTERIOR_MUT: () = {
// The "0." case is already ruled out by not permitting any interior mutability in `const`.
let _val: &'static _ = &(Cell::new(1), 2).1;
};
```
I assume something like `&Some(&(Cell::new(1), 2).1)` would hit the nested case inside `validate_rvalue`... though I am not sure why that would not just trigger nested promotion, first promoting the inner reference and then the outer one?
Fixes https://github.com/rust-lang/rust/issues/67534 (by simply rejecting that code^^)
r? `@oli-obk` (but for now this is not meant to be merged!)
Cc `@rust-lang/wg-const-eval`
Code like
impl Foo {
default fn foo() {}
}
will trigger the error
error: `default` is only allowed on items in `impl` definitions
--> src/lib.rs:5:5
|
5 | default fn foo() {}
| -------^^^^^^^^^
| |
| `default` because of this
but that's very confusing! I *did* put it on an item in an impl!
So this commit changes the message to
error: `default` is only allowed on items in trait impls
--> src/lib.rs:5:5
|
5 | default fn foo() {}
| -------^^^^^^^^^
| |
| `default` because of this
Compress RWU from at least 32 bits to 4 bits
The liveness uses a mixed representation of RWUs based on the
observation that most of them have invalid reader and invalid
writer. The packed variant uses 32 bits and unpacked 96 bits.
Unpacked data contains reader live node and writer live node.
Since live nodes are used only to determine their validity,
RWUs can always be stored in a packed form with four bits for
each: reader bit, writer bit, used bit, and one extra padding
bit to simplify packing and unpacking operations.
When encoding a proc-macro crate, there may be gaps in the table (since
we only encode the crate root and proc-macro items). Account for this by
checking if the entry is present, rather than using `unwrap()`
Replace simple `if let` constructs with Option::map
Replaces a few constructs of the form
```
if let Some(x) = var {
Some(...)
} else {
None
}
```
with calls to `Option::map`.
`@rustbot` modify labels +C-cleanup +T-compiler
Fixes: #79725
Some macros can create a situation where `fn_sig_span` and `body_span`
map to different files.
New documentation on coverage tests incorrectly assumed multiple test
binaries could just be listed at the end of the `llvm-cov` command,
but it turns out each binary needs a `--object` prefix.
This PR fixes the bug and updates the documentation to correct that
issue. It also fixes a few other minor issues in internal implementation
comments, and adds documentation on getting coverage results for doc
tests.
Validate naked functions definitions
Validate that naked functions are defined in terms of a single inline assembly
block that uses only `const` and `sym` operands and has `noreturn` option.
Implemented as future incompatibility lint with intention to migrate it into
hard error. When it becomes a hard error it will ensure that naked functions are
either unsafe or contain an unsafe block around the inline assembly. It will
guarantee that naked functions do not reference functions parameters (obsoleting
part of existing checks from #79411). It will limit the definitions of naked
functions to what can be reliably supported. It will also reject naked functions
implemented using legacy LLVM style assembly since it cannot satisfy those
conditions.
https://github.com/rust-lang/rfcs/pull/2774https://github.com/rust-lang/rfcs/pull/2972
- This allows us to delay figuring out the index of a capture
in the closure structure when all projections to atleast form
a capture have been applied to the builder
Co-authored-by: Roxane Fruytier <roxane.fruytier@hotmail.com>
- Derive TypeFoldable on `hir::place::Place` and associated
structs, to them to be written into typeck results.
Co-authored-by: Jennifer Wills <wills.jenniferg@gmail.com>
Co-authored-by: Logan Mosier <logmosier@gmail.com>
extend `WithOptConstParam` docs, move rustdoc test
This should hopefully make things a bit clearer, feel free to comment on anything which can still be improved.
cc `@ecstatic-morse` `@nikomatsakis` `@RalfJung`
Const parameters can not be inferred with `_` help note
This should close: #79557
# Example output
```
error[E0747]: type provided when a constant was expected
--> inferred_const_note.rs:6:19
|
6 | let a = foo::<_, 2>([0, 1, 2]);
| ^
|
= help: Const parameters can not be inferred with `_`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0747`.
```
r? `@lcnr`
The liveness uses a mixed representation of RWUs based on the
observation that most of them have invalid reader and invalid
writer. The packed variant uses 32 bits and unpacked 96 bits.
Unpacked data contains reader live node and writer live node.
Since live nodes are used only to determine their validity,
RWUs can always be stored in a packed form with four bits for
each: reader bit, writer bit, used bit, and one extra padding
bit to simplify packing and unpacking operations.
A slightly clearer diagnostic when misusing const
Fixes#79598
This produces the following diagnostic:
"expected one of `>`, a const expression, lifetime, or type, found keyword `const`"
Instead of the previous, more confusing:
"expected one of `>`, const, lifetime, or type, found keyword `const`"
This might not be completely clear as some users might not understand what a const expression is, but I do believe this is an improvement.
check the recursion limit when finding a struct's tail
fixes#79437
This does a `delay_span_bug` (via `ty_error_with_message`) rather than emit a new error message, under the assumption that there will be an error elsewhere (even if the type isn't infinitely recursive, just deeper than the recursion limit, this appears to be the case).
Fixes#79661
In incremental compilation mode, we update a `DefPathHash -> DefId`
mapping every time we create a `DepNode` for a foreign `DefId`.
This mapping is written out to the on-disk incremental cache, and is
read by the next compilation session to allow us to lazily decode
`DefId`s.
When we decode a `DepNode` from the current incremental cache, we need
to ensure that any previously-recorded `DefPathHash -> DefId` mapping
gets recorded in the new mapping that we write out. However, PR #74967
didn't do this in all cases, leading to us being unable to decode a
`DefPathHash` in certain circumstances.
This PR refactors some of the code around `DepNode` deserialization to
prevent this kind of mistake from happening again.
Fix perf regression caused by #79284https://github.com/rust-lang/rust/pull/79284 only moved code around but this changed inlining and caused a large perf regression. This fixes it for me, though I'm less confident than usual because the regression was not observable with my usual (i.e. incremental) compilation settings.
r? `@Mark-Simulacrum`
Coverage tests for remaining TerminatorKinds and async, improve Assert
Tested and validate results for panic unwind, panic abort, assert!()
macro, TerminatorKind::Assert (for example, numeric overflow), and
async/await.
Implemented a previous documented idea to change Assert handling to be
the same as FalseUnwind and Goto, so it doesn't get its own
BasicCoverageBlock anymore. This changed a couple of coverage regions,
but I validated those changes are not any worse than the prior results,
and probably help assure some consistency (even if some people might
disagree with how the code region is consistently computed).
Fixed issue with async/await. AggregateKind::Generator needs to be
handled like AggregateKind::Closure; coverage span for the outer async
function should not "cover" the async body, which is actually executed
in a separate "closure" MIR.
Fix some clippy lints
Happy to revert these if you think they're less readable, but personally I like them better now (especially the `else { if { ... } }` to `else if { ... }` change).
Added one more test (two files) showing coverage of generics and unused
functions across crates.
Created and referenced new Issues, as requested.
Added comments.
Added a note about the possible effects of compiler options on LLVM
coverage maps.
Fixes multiple issue with counters, with simplification
Includes a change to the implicit else span in ast_lowering, so coverage
of the implicit else no longer spans the `then` block.
Adds coverage for unused closures and async function bodies.
Fixes: #78542
Adding unreachable regions for known MIR missing from coverage map
Cleaned up PR commits, and removed link-dead-code requirement and tests
Coverage no longer depends on Issue #76038 (`-C link-dead-code` is
no longer needed or enforced, so MSVC can use the same tests as
Linux and MacOS now)
Restrict adding unreachable regions to covered files
Improved the code that adds coverage for uncalled functions (with MIR
but not-codegenned) to avoid generating coverage in files not already
included in the files with covered functions.
Resolved last known issue requiring --emit llvm-ir workaround
Fixed bugs in how unreachable code spans were added.
Tested and validate results for panic unwind, panic abort, assert!()
macro, TerminatorKind::Assert (for example, numeric overflow), and
async/await.
Implemented a previous documented idea to change Assert handling to be
the same as FalseUnwind and Goto, so it doesn't get its own
BasicCoverageBlock anymore. This changed a couple of coverage regions,
but I validated those changes are not any worse than the prior results,
and probably help assure some consistency (even if some people might
disagree with how the code region is consistently computed).
Fixed issue with async/await. AggregateKind::Generator needs to be
handled like AggregateKind::Closure; coverage span for the outer async
function should not "cover" the async body, which is actually executed
in a separate "closure" MIR.
Fix `unknown-crate` when using -Z self-profile with rustdoc
... by removing a duplicate `crate_name` field in `interface::Config`,
making it clear that rustdoc should be passing it to `config::Options` instead.
Unblocks https://github.com/rust-lang/rustc-perf/issues/797.
Revert "Auto merge of #79209
r? `@nikomatsakis`
This has caused some issues (#79560) so better to revert and try to come up with a proper fix without rush.
Do not show negative polarity trait implementations in diagnostic messages for similar implementations
This fixes#79458.
Previously, this code:
```rust
#[derive(Clone)]
struct Foo<'a, T> {
x: &'a mut T,
}
```
would have suggested that `<&mut T as Clone>` was an implementation that was found. This is due to the fact that the standard library now has `impl<'_, T> !Clone for &'_ mut T`, and explicit negative polarity implementations were not filtered out in diagnostic output when suggesting similar implementations.
This PR fixes this issue by filtering out negative polarity trait implementations in `find_similar_impl_candidates` within `rustc_trait_selection::traits::error_reporting::InferCtxtPrivExt<'tcx>`. It also adds a UI regression test for this issue and fixes UI tests that had incorrectly been modified to expect the invalid output.
r? `@scottmcm`
