Raw Pointers are Constant PatKinds too #144573
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lcnr
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@bors r=lcnr rollup |
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| /// * integer, bool, char or float (represented as a valtree), which will be handled by | ||
| /// exhaustiveness to cover exactly its own value, similar to `&str`, but these values are | ||
| /// much simpler. | ||
| /// * raw pointers derived from integers, other raw pointers will have already resulted in an |
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This will also be a valtree then.
Hm, that makes me wonder whether we shouldn't change the type here from mir::Const to something that enforces val-tree-ness... that was part of the goal of the big const pattern changes we did last year.
I don't know how the String case is represented though.
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Yeah I don't know about the String case :3 mir::Const does seem a bit funny to me too
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… r=lcnr
Raw Pointers are Constant PatKinds too
raw pointers can be matched on with a const pattern:
```rust
const FOO: *const u8 = core::ptr::null();
fn foo(a: *const u8) {
match a {
FOO => (),
_ => todo!(),
}
}
```
as far as I can tell this is represented with a `PatKind::Constant`: https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs#L333-L337
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Rollup of 11 pull requests Successful merges: - #143289 (Remove `[T]::array_chunks(_mut)`) - #143883 (Add `--link-targets-dir` argument to linkchecker) - #144034 (tests: Test line number in debuginfo for diverging function calls) - #144236 (Add `core::mem::DropGuard`) - #144268 (Add method `find_ancestor_not_from_macro` and `find_ancestor_not_from_extern_macro` to supersede `find_oldest_ancestor_in_same_ctxt`) - #144303 (Consolidate staging for `rustc_private` tools) - #144539 (constify with_exposed_provenance) - #144569 (rustc-dev-guide subtree update) - #144573 (Raw Pointers are Constant PatKinds too) - #144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.) - #144582 (fix `Atomic*::as_ptr` wording) r? `@ghost` `@rustbot` modify labels: rollup
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… r=lcnr
Raw Pointers are Constant PatKinds too
raw pointers can be matched on with a const pattern:
```rust
const FOO: *const u8 = core::ptr::null();
fn foo(a: *const u8) {
match a {
FOO => (),
_ => todo!(),
}
}
```
as far as I can tell this is represented with a `PatKind::Constant`: https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs#L333-L337
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Jul 29, 2025
… r=lcnr
Raw Pointers are Constant PatKinds too
raw pointers can be matched on with a const pattern:
```rust
const FOO: *const u8 = core::ptr::null();
fn foo(a: *const u8) {
match a {
FOO => (),
_ => todo!(),
}
}
```
as far as I can tell this is represented with a `PatKind::Constant`: https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs#L333-L337
Zalathar
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… r=lcnr
Raw Pointers are Constant PatKinds too
raw pointers can be matched on with a const pattern:
```rust
const FOO: *const u8 = core::ptr::null();
fn foo(a: *const u8) {
match a {
FOO => (),
_ => todo!(),
}
}
```
as far as I can tell this is represented with a `PatKind::Constant`: https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs#L333-L337
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Rollup of 11 pull requests Successful merges: - #143883 (Add `--link-targets-dir` argument to linkchecker) - #144236 (Add `core::mem::DropGuard`) - #144303 (Consolidate staging for `rustc_private` tools) - #144367 (Move dist-apple-various from x86_64 to aarch64) - #144539 (constify with_exposed_provenance) - #144569 (rustc-dev-guide subtree update) - #144573 (Raw Pointers are Constant PatKinds too) - #144575 (fixed typo chunks->as_chunks) - #144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.) - #144582 (fix `Atomic*::as_ptr` wording) - #144616 (coverage: Regression test for "function name is empty" bug) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 10 pull requests Successful merges: - #143883 (Add `--link-targets-dir` argument to linkchecker) - #144236 (Add `core::mem::DropGuard`) - #144367 (Move dist-apple-various from x86_64 to aarch64) - #144539 (constify with_exposed_provenance) - #144569 (rustc-dev-guide subtree update) - #144573 (Raw Pointers are Constant PatKinds too) - #144575 (fixed typo chunks->as_chunks) - #144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.) - #144582 (fix `Atomic*::as_ptr` wording) - #144616 (coverage: Regression test for "function name is empty" bug) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #144573 - BoxyUwU:patkind_constant_ptr_docs, r=lcnr Raw Pointers are Constant PatKinds too raw pointers can be matched on with a const pattern: ```rust const FOO: *const u8 = core::ptr::null(); fn foo(a: *const u8) { match a { FOO => (), _ => todo!(), } } ``` as far as I can tell this is represented with a `PatKind::Constant`: https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs#L333-L337
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Rollup of 10 pull requests Successful merges: - rust-lang/rust#143883 (Add `--link-targets-dir` argument to linkchecker) - rust-lang/rust#144236 (Add `core::mem::DropGuard`) - rust-lang/rust#144367 (Move dist-apple-various from x86_64 to aarch64) - rust-lang/rust#144539 (constify with_exposed_provenance) - rust-lang/rust#144569 (rustc-dev-guide subtree update) - rust-lang/rust#144573 (Raw Pointers are Constant PatKinds too) - rust-lang/rust#144575 (fixed typo chunks->as_chunks) - rust-lang/rust#144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.) - rust-lang/rust#144582 (fix `Atomic*::as_ptr` wording) - rust-lang/rust#144616 (coverage: Regression test for "function name is empty" bug) r? `@ghost` `@rustbot` modify labels: rollup
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raw pointers can be matched on with a const pattern:
as far as I can tell this is represented with a
PatKind::Constant: https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs#L333-L337