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Merged
merged 1 commit into from
Apr 15, 2025
Merged

Allow const patterns of matches to contain pattern types #138393

merged 1 commit into from
Apr 15, 2025

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oli-obk
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@oli-obk oli-obk commented Mar 12, 2025

Trying to pattern match on a type containing a pattern type will currently fail with an ICE

error: internal compiler error: compiler/rustc_mir_build/src/builder/matches/test.rs:459:18: invalid type for non-scalar compare: (u32) is 1..
  --> src/main.rs:22:5
   |
22 |     TWO => {}
   |     ^^^

because the compiler tries to generate a MIR BinOp(Eq) operation on a pattern type, which is not supported. While we could support that, there are side effects of allowing this (none that would compile, but the compiler would simultaneously think it could == pattern types and that it could not because PartialEq is not implemented. So instead I change the logic for pattern matching to transmute pattern types to their base type before comparing.

r? @BoxyUwU

cc #123646 @scottmcm @joshtriplett

@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Mar 12, 2025
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rustbot commented Mar 12, 2025

Some changes occurred in match lowering

cc @Nadrieril

@BoxyUwU BoxyUwU added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Mar 26, 2025
@oli-obk oli-obk force-pushed the pattern-type-in-pattern branch from a464513 to 0fe88f5 Compare April 7, 2025 10:04
@oli-obk oli-obk added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Apr 7, 2025
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@oli-obk oli-obk force-pushed the pattern-type-in-pattern branch from 0fe88f5 to 0842836 Compare April 7, 2025 11:05
BoxyUwU
BoxyUwU reviewed Apr 14, 2025
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tests/ui/type/pattern_types/derives_fail.rs Outdated
@@ -0,0 +1,26 @@
//! Check that pattern types don't implement traits of their base automatically.
//! Exceptions are `Clone` and `Copy`.
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what makes clone/copy work?

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they are builtin impls. added that as a comment here

@BoxyUwU BoxyUwU added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Apr 14, 2025
@oli-obk oli-obk force-pushed the pattern-type-in-pattern branch from 0842836 to 71412c0 Compare April 14, 2025 14:27
@oli-obk oli-obk force-pushed the pattern-type-in-pattern branch from 71412c0 to 7ad1697 Compare April 14, 2025 14:27
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BoxyUwU commented Apr 14, 2025

@bors r+

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bors commented Apr 14, 2025

📌 Commit 7ad1697 has been approved by BoxyUwU

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Apr 14, 2025
Zalathar added a commit to Zalathar/rust that referenced this pull request Apr 15, 2025
@Zalathar
Rollup merge of rust-lang#138393 - oli-obk:pattern-type-in-pattern, r…
a295c7e 
…=BoxyUwU

Allow const patterns of matches to contain pattern types

Trying to pattern match on a type containing a pattern type will currently fail with an ICE

```rust
error: internal compiler error: compiler/rustc_mir_build/src/builder/matches/test.rs:459:18: invalid type for non-scalar compare: (u32) is 1..
  --> src/main.rs:22:5
   |
22 |     TWO => {}
   |     ^^^
```

because the compiler tries to generate a MIR `BinOp(Eq)` operation on a pattern type, which is not supported. While we could support that, there are side effects of allowing this (none that would compile, but the compiler would simultaneously think it could `==` pattern types and that it could not because `PartialEq` is not implemented. So instead I change the logic for pattern matching to transmute pattern types to their base type before comparing.

r? `@BoxyUwU`

cc rust-lang#123646 `@scottmcm` `@joshtriplett`
@Zalathar Zalathar mentioned this pull request Apr 15, 2025
Closed
bors added a commit to rust-lang-ci/rust that referenced this pull request Apr 15, 2025
@bors
Auto merge of rust-lang#139837 - Zalathar:rollup-hqr9nyf, r=Zalathar
748c7c1 
Rollup of 12 pull requests

Successful merges:

 - rust-lang#138374 (Enable contracts for const functions)
 - rust-lang#138380 (ci: add runners for vanilla LLVM 20)
 - rust-lang#138393 (Allow const patterns of matches to contain pattern types)
 - rust-lang#139393 (rustdoc-json: Output target feature information)
 - rust-lang#139517 (std: sys: process: uefi: Use NULL stdin by default)
 - rust-lang#139554 (std: add Output::exit_ok)
 - rust-lang#139745 (Avoid unused clones in `Cloned<I>` and `Copied<I>`)
 - rust-lang#139757 (opt-dist: use executable-extension for host llvm-profdata)
 - rust-lang#139778 (Add test for issue 34834)
 - rust-lang#139783 (Use `compiletest-ignore-dir` for bootstrap self-tests)
 - rust-lang#139789 (do not unnecessarily leak auto traits in item bounds)
 - rust-lang#139791 (drop global where-bounds before merging candidates)

r? `@ghost`
`@rustbot` modify labels: rollup
jieyouxu added a commit to jieyouxu/rust that referenced this pull request Apr 15, 2025
@jieyouxu
Rollup merge of rust-lang#138393 - oli-obk:pattern-type-in-pattern, r…
5a5bda9 
…=BoxyUwU

Allow const patterns of matches to contain pattern types

Trying to pattern match on a type containing a pattern type will currently fail with an ICE

```rust
error: internal compiler error: compiler/rustc_mir_build/src/builder/matches/test.rs:459:18: invalid type for non-scalar compare: (u32) is 1..
  --> src/main.rs:22:5
   |
22 |     TWO => {}
   |     ^^^
```

because the compiler tries to generate a MIR `BinOp(Eq)` operation on a pattern type, which is not supported. While we could support that, there are side effects of allowing this (none that would compile, but the compiler would simultaneously think it could `==` pattern types and that it could not because `PartialEq` is not implemented. So instead I change the logic for pattern matching to transmute pattern types to their base type before comparing.

r? ``@BoxyUwU``

cc rust-lang#123646 ``@scottmcm`` ``@joshtriplett``
@jieyouxu jieyouxu mentioned this pull request Apr 15, 2025
Closed
@Zalathar Zalathar mentioned this pull request Apr 15, 2025
Merged
bors added a commit to rust-lang-ci/rust that referenced this pull request Apr 15, 2025
@bors
Auto merge of rust-lang#139845 - Zalathar:rollup-u5u5y1v, r=Zalathar
f433fa4 
Rollup of 17 pull requests

Successful merges:

 - rust-lang#138374 (Enable contracts for const functions)
 - rust-lang#138380 (ci: add runners for vanilla LLVM 20)
 - rust-lang#138393 (Allow const patterns of matches to contain pattern types)
 - rust-lang#139517 (std: sys: process: uefi: Use NULL stdin by default)
 - rust-lang#139554 (std: add Output::exit_ok)
 - rust-lang#139660 (compiletest: Add an experimental new executor to replace libtest)
 - rust-lang#139669 (Overhaul `AssocItem`)
 - rust-lang#139671 (Proc macro span API redesign: Replace proc_macro::SourceFile by Span::{file, local_file})
 - rust-lang#139750 (std/thread: Use default stack size from menuconfig for NuttX)
 - rust-lang#139772 (Remove `hir::Map`)
 - rust-lang#139785 (Let CStrings be either 1 or 2 byte aligned.)
 - rust-lang#139789 (do not unnecessarily leak auto traits in item bounds)
 - rust-lang#139791 (drop global where-bounds before merging candidates)
 - rust-lang#139798 (normalize: prefer `ParamEnv` over `AliasBound` candidates)
 - rust-lang#139822 (Fix: Map EOPNOTSUPP to ErrorKind::Unsupported on Unix)
 - rust-lang#139833 (Fix some HIR pretty-printing problems)
 - rust-lang#139836 (Basic tests of MPMC receiver cloning)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit aa9a80c into rust-lang:master Apr 15, 2025
6 checks passed
@rustbot rustbot added this to the 1.88.0 milestone Apr 15, 2025
rust-timer added a commit to rust-lang-ci/rust that referenced this pull request Apr 15, 2025
@rust-timer
Unrolled build for rust-lang#138393
26b6b0a 
Rollup merge of rust-lang#138393 - oli-obk:pattern-type-in-pattern, r=BoxyUwU

Allow const patterns of matches to contain pattern types

Trying to pattern match on a type containing a pattern type will currently fail with an ICE

```rust
error: internal compiler error: compiler/rustc_mir_build/src/builder/matches/test.rs:459:18: invalid type for non-scalar compare: (u32) is 1..
  --> src/main.rs:22:5
   |
22 |     TWO => {}
   |     ^^^
```

because the compiler tries to generate a MIR `BinOp(Eq)` operation on a pattern type, which is not supported. While we could support that, there are side effects of allowing this (none that would compile, but the compiler would simultaneously think it could `==` pattern types and that it could not because `PartialEq` is not implemented. So instead I change the logic for pattern matching to transmute pattern types to their base type before comparing.

r? ```@BoxyUwU```

cc rust-lang#123646 ```@scottmcm``` ```@joshtriplett```
github-actions bot pushed a commit to model-checking/verify-rust-std that referenced this pull request Apr 19, 2025
@bors
Auto merge of rust-lang#139845 - Zalathar:rollup-u5u5y1v, r=Zalathar
885f27c 
Rollup of 17 pull requests

Successful merges:

 - rust-lang#138374 (Enable contracts for const functions)
 - rust-lang#138380 (ci: add runners for vanilla LLVM 20)
 - rust-lang#138393 (Allow const patterns of matches to contain pattern types)
 - rust-lang#139517 (std: sys: process: uefi: Use NULL stdin by default)
 - rust-lang#139554 (std: add Output::exit_ok)
 - rust-lang#139660 (compiletest: Add an experimental new executor to replace libtest)
 - rust-lang#139669 (Overhaul `AssocItem`)
 - rust-lang#139671 (Proc macro span API redesign: Replace proc_macro::SourceFile by Span::{file, local_file})
 - rust-lang#139750 (std/thread: Use default stack size from menuconfig for NuttX)
 - rust-lang#139772 (Remove `hir::Map`)
 - rust-lang#139785 (Let CStrings be either 1 or 2 byte aligned.)
 - rust-lang#139789 (do not unnecessarily leak auto traits in item bounds)
 - rust-lang#139791 (drop global where-bounds before merging candidates)
 - rust-lang#139798 (normalize: prefer `ParamEnv` over `AliasBound` candidates)
 - rust-lang#139822 (Fix: Map EOPNOTSUPP to ErrorKind::Unsupported on Unix)
 - rust-lang#139833 (Fix some HIR pretty-printing problems)
 - rust-lang#139836 (Basic tests of MPMC receiver cloning)

r? `@ghost`
`@rustbot` modify labels: rollup
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