Revert #131669 due to ICEs
Revert [lint: change help for pointers to dyn types in FFI #131669](https://github.com/rust-lang/rust/pull/131669) due to ICE reports:
- <https://github.com/rust-lang/rust/issues/134059> (real-world)
- <https://github.com/rust-lang/rust/issues/134060> (fuzzing)
Closes#134060.
The revert criteria I used to assess whether to post this revert was:
1. It's not trivial to fix-forward. (1) The implementation itself is tricky due to `tcx.is_sized` query not being very trivial. (2) It will need more extensive test coverage for different ty kinds.
2. It is impacting real-world crates, i.e. #134059.
3. `improper_ctypes_definitions` is a warn-by-default lint.
This revert is without prejudice to relanding the changes. The changes can be re-landed with those cases addressed and stronger test coverage.
A rough regression test corresponding to the fuzzed example reported in #134060 is added to check that the revert worked, it is not sufficient for the lint test coverage when the lint improvements are to be relanded. Please feel free to improve the test in the reland.
r? `@workingjubilee` (or compiler)
cc `@niacdoial` (PR author)
Introduce `MixedBitSet`
`ChunkedBitSet` is good at avoiding excessive memory usage for programs with very large functgions where dataflow bitsets have very large domain sizes. But it's overly heavyweight for small bitsets, because any non-empty `ChunkedBitSet` takes up at least 256 bytes.
This PR introduces `MixedBitSet`, which is a simple bitset that uses `BitSet` for small/medium bitsets and `ChunkedBitSet` for large bitsets. It's a speed and memory usage win.
r? `@Mark-Simulacrum`
A bunch of cleanups
These are all extracted from a branch I have to get rid of driver queries. Most of the commits are not directly necessary for this, but were found in the process of implementing the removal of driver queries.
Previous PR: https://github.com/rust-lang/rust/pull/132410
A `ChunkedBitSet` has to be at least 2048 bits for it to outperform a
`BitSet`, because that's the chunk size. The largest `SparseBitMatrix`
encountered when compiling the compiler and the entire rustc-perf
benchmark suite is less than 600 bits.
This change is a tiny perf win, but the motivation is more about
avoiding uses of `ChunkedBitSet` outside of `MixedBitSet`.
The test change is necessary to avoid hitting the `<BitSet<T> as
BitRelations<ChunkedBitSet<T>>>::subtract` method that has
`unimplemented!` in its body and isn't otherwise used.
Remove unnecessary `int_type_width_signed` function
This can just use `Ty::int_size_and_signed` instead of making its own version.
You might want to look at this [ignoring whitespace](https://github.com/rust-lang/rust/pull/134020/files?w=1) since a huge bunch of code got un-indented.
Fix: typo in E0751 error explanation
Corrected a grammatical error in the explanation for E0751. Changed "exists" to "exist" to improve clarity and ensure proper grammar in the error message.
Actually walk into lifetimes and attrs in `EarlyContextAndPass`
Visitors that don't also call `walk_*` are kinda a footgun...
I believe all the other early lint functions walk into their types correctly at this point.
Add allocate_bytes and refactor allocate_str in InterpCx for raw byte…
Fixes https://github.com/rust-lang/miri/issues/4025
This PR introduces a new `allocate_bytes` function in InterpCx and refactors `allocate_str` to use it internally. This change improves memory allocation handling in the interpreter by:
1. Adding `allocate_bytes`:
- Direct byte slice allocation support
- Handles both mutable and immutable allocations
- Maintains proper memory alignment and deduplication
2. Refactoring `allocate_str`:
- Now uses `allocate_bytes` internally
- Adds string-specific metadata handling
- Preserves existing string allocation behavior
This is part 1 of the planned changes to improve timezone string handling in Miri. A follow-up PR will update Miri's timezone logic to use this new allocation mechanism.
Related: https://github.com/rust-lang/miri/pull/4069
Add more info on type/trait mismatches for different crate versions
When encountering a type or trait mismatch for two types coming from two different crates with the same name, detect if it is either mixing two types/traits from the same crate on different versions:
```
error[E0308]: mismatched types
--> replaced
|
LL | do_something_type(Type);
| ----------------- ^^^^ expected `dependency::Type`, found `dep_2_reexport::Type`
| |
| arguments to this function are incorrect
|
note: two different versions of crate `dependency` are being used; two types coming from two different versions of the same crate are different types even if they look the same
--> replaced
|
LL | pub struct Type(pub i32);
| ^^^^^^^^^^^^^^^ this is the expected type `dependency::Type`
|
::: replaced
|
LL | pub struct Type;
| ^^^^^^^^^^^^^^^ this is the found type `dep_2_reexport::Type`
|
::: replaced
|
LL | extern crate dep_2_reexport;
| ---------------------------- one version of crate `dependency` is used here, as a dependency of crate `foo`
LL | extern crate dependency;
| ------------------------ one version of crate `dependency` is used here, as a direct dependency of the current crate
= help: you can use `cargo tree` to explore your dependency tree
note: function defined here
--> replaced
|
LL | pub fn do_something_type(_: Type) {}
| ^^^^^^^^^^^^^^^^^
error[E0308]: mismatched types
--> replaced
|
LL | do_something_trait(Box::new(Type) as Box<dyn Trait2>);
| ------------------ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected trait `dependency::Trait2`, found trait `dep_2_reexport::Trait2`
| |
| arguments to this function are incorrect
|
note: two different versions of crate `dependency` are being used; two types coming from two different versions of the same crate are different types even if they look the same
--> replaced
|
LL | pub trait Trait2 {}
| ^^^^^^^^^^^^^^^^ this is the expected trait `dependency::Trait2`
|
::: replaced
|
LL | pub trait Trait2 {}
| ^^^^^^^^^^^^^^^^ this is the found trait `dep_2_reexport::Trait2`
|
::: replaced
|
LL | extern crate dep_2_reexport;
| ---------------------------- one version of crate `dependency` is used here, as a dependency of crate `foo`
LL | extern crate dependency;
| ------------------------ one version of crate `dependency` is used here, as a direct dependency of the current crate
= help: you can use `cargo tree` to explore your dependency tree
note: function defined here
--> replaced
|
LL | pub fn do_something_trait(_: Box<dyn Trait2>) {}
| ^^^^^^^^^^^^^^^^^^
```
or if it is different crates that were renamed to the same name:
```
error[E0308]: mismatched types
--> $DIR/type-mismatch-same-crate-name.rs:21:20
|
LL | a::try_foo(foo2);
| ---------- ^^^^ expected `main:🅰️:Foo`, found a different `main:🅰️:Foo`
| |
| arguments to this function are incorrect
|
note: two types coming from two different crates are different types even if they look the same
--> $DIR/auxiliary/crate_a2.rs:1:1
|
LL | pub struct Foo;
| ^^^^^^^^^^^^^^ this is the found type `crate_a2::Foo`
|
::: $DIR/auxiliary/crate_a1.rs:1:1
|
LL | pub struct Foo;
| ^^^^^^^^^^^^^^ this is the expected type `crate_a1::Foo`
|
::: $DIR/type-mismatch-same-crate-name.rs:13:17
|
LL | let foo2 = {extern crate crate_a2 as a; a::Foo};
| --------------------------- one type comes from crate `crate_a2` is used here, which is renamed locally to `a`
...
LL | extern crate crate_a1 as a;
| --------------------------- one type comes from crate `crate_a1` is used here, which is renamed locally to `a`
note: function defined here
--> $DIR/auxiliary/crate_a1.rs:10:8
|
LL | pub fn try_foo(x: Foo){}
| ^^^^^^^
error[E0308]: mismatched types
--> $DIR/type-mismatch-same-crate-name.rs:27:20
|
LL | a::try_bar(bar2);
| ---------- ^^^^ expected trait `main:🅰️:Bar`, found a different trait `main:🅰️:Bar`
| |
| arguments to this function are incorrect
|
note: two types coming from two different crates are different types even if they look the same
--> $DIR/auxiliary/crate_a2.rs:3:1
|
LL | pub trait Bar {}
| ^^^^^^^^^^^^^ this is the found trait `crate_a2::Bar`
|
::: $DIR/auxiliary/crate_a1.rs:3:1
|
LL | pub trait Bar {}
| ^^^^^^^^^^^^^ this is the expected trait `crate_a1::Bar`
|
::: $DIR/type-mismatch-same-crate-name.rs:13:17
|
LL | let foo2 = {extern crate crate_a2 as a; a::Foo};
| --------------------------- one trait comes from crate `crate_a2` is used here, which is renamed locally to `a`
...
LL | extern crate crate_a1 as a;
| --------------------------- one trait comes from crate `crate_a1` is used here, which is renamed locally to `a`
note: function defined here
--> $DIR/auxiliary/crate_a1.rs:11:8
|
LL | pub fn try_bar(x: Box<Bar>){}
| ^^^^^^^
```
This new output unifies the E0308 errors detail with the pre-existing E0277 errors, and better differentiates the "`extern crate` renamed" and "same crate, different versions" cases.
lint: change help for pointers to dyn types in FFI
### Context
while playing around, I encountered the warning for dyn types in `extern "C"` functions, but even after that I assumed that a (rust) raw pointer could be interpreted in C ('s ABI) as a `void *`... to be fair part of why I ignored the warning is because I wanted to poke at the generated assembly, not make useful code.
### Example
```rust
extern "C"
fn caller(callee: *const dyn Fn(i32)->i32){
// -- snip --
}
```
old warning:
```
warning: `extern` fn uses type `dyn Fn(i32) -> i32`, which is not FFI-safe
--> file/name.rs:42:19
|
42 | fn caller(callee: *const dyn Fn(i32)->i32) {
| ^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
|
= note: trait objects have no C equivalent
= note: `#[warn(improper_ctypes_definitions)]` on by default
```
new warning:
```
warning: `extern` fn uses type `dyn Fn(i32) -> i32`, which is not FFI-safe
--> file/name.rs:42:19
|
42 | fn caller(callee: *const dyn Fn(i32)->i32) -> (){
| ^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
|
= note: this pointer to an unsized type contains metadata, which makes it incompatible with a C pointer
= note: `#[warn(improper_ctypes_definitions)]` on by default
```
On nightly, we mention the trait is unstable
```
error[E0277]: the trait bound `T: Unstable` is not satisfied
--> $DIR/unstable-trait-suggestion.rs:13:9
|
LL | foo(t)
| --- ^ the trait `Unstable` is not implemented for `T`
| |
| required by a bound introduced by this call
|
note: required by a bound in `foo`
--> $DIR/unstable-trait-suggestion.rs:9:11
|
LL | fn foo<T: Unstable>(_: T) {}
| ^^^^^^^^ required by this bound in `foo`
help: consider restricting type parameter `T` but it is an `unstable` trait
|
LL | pub fn demo<T: Unstable>(t: T) {
| ++++++++++
```
On stable, we don't suggest the trait at all
```
error[E0277]: the trait bound `T: Unstable` is not satisfied
--> $DIR/unstable-trait-suggestion.rs:13:9
|
LL | foo(t)
| --- ^ the trait `Unstable` is not implemented for `T`
| |
| required by a bound introduced by this call
|
note: required by a bound in `foo`
--> $DIR/unstable-trait-suggestion.rs:9:11
|
LL | fn foo<T: Unstable>(_: T) {}
| ^^^^^^^^ required by this bound in `foo`
```
When encountering a type or trait mismatch for two types coming from two different crates with the same name, detect if it is either mixing two types/traits from the same crate on different versions:
```
error[E0308]: mismatched types
--> replaced
|
LL | do_something_type(Type);
| ----------------- ^^^^ expected `dependency::Type`, found `dep_2_reexport::Type`
| |
| arguments to this function are incorrect
|
note: two different versions of crate `dependency` are being used; two types coming from two different versions of the same crate are different types even if they look the same
--> replaced
|
LL | pub struct Type(pub i32);
| ^^^^^^^^^^^^^^^ this is the expected type `dependency::Type`
|
::: replaced
|
LL | pub struct Type;
| ^^^^^^^^^^^^^^^ this is the found type `dep_2_reexport::Type`
|
::: replaced
|
LL | extern crate dep_2_reexport;
| ---------------------------- one version of crate `dependency` is used here, as a dependency of crate `foo`
LL | extern crate dependency;
| ------------------------ one version of crate `dependency` is used here, as a direct dependency of the current crate
= help: you can use `cargo tree` to explore your dependency tree
note: function defined here
--> replaced
|
LL | pub fn do_something_type(_: Type) {}
| ^^^^^^^^^^^^^^^^^
error[E0308]: mismatched types
--> replaced
|
LL | do_something_trait(Box::new(Type) as Box<dyn Trait2>);
| ------------------ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected trait `dependency::Trait2`, found trait `dep_2_reexport::Trait2`
| |
| arguments to this function are incorrect
|
note: two different versions of crate `dependency` are being used; two types coming from two different versions of the same crate are different types even if they look the same
--> replaced
|
LL | pub trait Trait2 {}
| ^^^^^^^^^^^^^^^^ this is the expected trait `dependency::Trait2`
|
::: replaced
|
LL | pub trait Trait2 {}
| ^^^^^^^^^^^^^^^^ this is the found trait `dep_2_reexport::Trait2`
|
::: replaced
|
LL | extern crate dep_2_reexport;
| ---------------------------- one version of crate `dependency` is used here, as a dependency of crate `foo`
LL | extern crate dependency;
| ------------------------ one version of crate `dependency` is used here, as a direct dependency of the current crate
= help: you can use `cargo tree` to explore your dependency tree
note: function defined here
--> replaced
|
LL | pub fn do_something_trait(_: Box<dyn Trait2>) {}
| ^^^^^^^^^^^^^^^^^^
```
or if it is different crates that were renamed to the same name:
```
error[E0308]: mismatched types
--> $DIR/type-mismatch-same-crate-name.rs:21:20
|
LL | a::try_foo(foo2);
| ---------- ^^^^ expected `main:🅰️:Foo`, found a different `main:🅰️:Foo`
| |
| arguments to this function are incorrect
|
note: two types coming from two different crates are different types even if they look the same
--> $DIR/auxiliary/crate_a2.rs:1:1
|
LL | pub struct Foo;
| ^^^^^^^^^^^^^^ this is the found type `crate_a2::Foo`
|
::: $DIR/auxiliary/crate_a1.rs:1:1
|
LL | pub struct Foo;
| ^^^^^^^^^^^^^^ this is the expected type `crate_a1::Foo`
|
::: $DIR/type-mismatch-same-crate-name.rs:13:17
|
LL | let foo2 = {extern crate crate_a2 as a; a::Foo};
| --------------------------- one type comes from crate `crate_a2` is used here, which is renamed locally to `a`
...
LL | extern crate crate_a1 as a;
| --------------------------- one type comes from crate `crate_a1` is used here, which is renamed locally to `a`
note: function defined here
--> $DIR/auxiliary/crate_a1.rs:10:8
|
LL | pub fn try_foo(x: Foo){}
| ^^^^^^^
error[E0308]: mismatched types
--> $DIR/type-mismatch-same-crate-name.rs:27:20
|
LL | a::try_bar(bar2);
| ---------- ^^^^ expected trait `main:🅰️:Bar`, found a different trait `main:🅰️:Bar`
| |
| arguments to this function are incorrect
|
note: two types coming from two different crates are different types even if they look the same
--> $DIR/auxiliary/crate_a2.rs:3:1
|
LL | pub trait Bar {}
| ^^^^^^^^^^^^^ this is the found trait `crate_a2::Bar`
|
::: $DIR/auxiliary/crate_a1.rs:3:1
|
LL | pub trait Bar {}
| ^^^^^^^^^^^^^ this is the expected trait `crate_a1::Bar`
|
::: $DIR/type-mismatch-same-crate-name.rs:13:17
|
LL | let foo2 = {extern crate crate_a2 as a; a::Foo};
| --------------------------- one trait comes from crate `crate_a2` is used here, which is renamed locally to `a`
...
LL | extern crate crate_a1 as a;
| --------------------------- one trait comes from crate `crate_a1` is used here, which is renamed locally to `a`
note: function defined here
--> $DIR/auxiliary/crate_a1.rs:11:8
|
LL | pub fn try_bar(x: Box<Bar>){}
| ^^^^^^^
```
This new output unifies the E0308 errors detail with the pre-existing E0277 errors, and better differentiates the "`extern crate` renamed" and "same crate, different versions" cases.
Remove a lit_to_const call
We have so many special cases of `match expr.kind { Lit() => {}, Unary(Neg, Lit()) => {} }`... I'm trying to figure out how to get these all unified, but outright removing some is good, too. So let's try it.
Tho we don't have many `const {}` blocks in the perf test suite... But I also don't know how common `const { 42 }` blocks are, I'd expect these to occur mostly from macros (like `thread_local!`)
Corrected a grammatical error in the explanation for E0751. Changed "exists" to "exist" to improve clarity and ensure proper grammar in the error message.
Hide errors whose suggestions would contain error constants or types
best reviewed commit-by-commit.
This is work towards cleaning up everything around `lit_to_const` and its mir equivalent.
fixes#123809
Do not implement unsafe auto traits for types with unsafe fields
If a type has unsafe fields, its safety invariants are not simply the conjunction of its field types' safety invariants. Consequently, it's invalid to reason about the safety properties of these types in a purely structural manner — i.e., the manner in which `auto` traits are implemented. Consequently, auto implementations of unsafe auto traits should not be generated for types with unsafe fields.
Tracking: #132922
r? `@compiler-errors`
It was inconsistently done (sometimes even within a single function) and
most of the rest of the compiler uses fatal errors instead, which need
to be caught using catch_with_exit_code anyway. Using fatal errors
instead of ErrorGuaranteed everywhere in the driver simplifies things a
bit.
