rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Leave promoteds untainted by errors when borrowck fails

Browse Source 
Previously, when borrowck failed it would taint all promoteds within the MIR
body. An attempt to evaluated the promoteds would subsequently fail with
spurious "note: erroneous constant used". For example:

```console
...
note: erroneous constant used
 --> tests/ui/borrowck/tainted-promoteds.rs:7:9
  |
7 |     a = &0 * &1 * &2 * &3;
  |         ^^

note: erroneous constant used
 --> tests/ui/borrowck/tainted-promoteds.rs:7:14
  |
7 |     a = &0 * &1 * &2 * &3;
  |              ^^

note: erroneous constant used
 --> tests/ui/borrowck/tainted-promoteds.rs:7:19
  |
7 |     a = &0 * &1 * &2 * &3;
  |                   ^^

note: erroneous constant used
 --> tests/ui/borrowck/tainted-promoteds.rs:7:24
  |
7 |     a = &0 * &1 * &2 * &3;
  |                        ^^
```

Borrowck failure doesn't indicate that there is anything wrong with
promoteds. Leave them untainted.
This commit is contained in:
Tomasz Miąsko
2023-04-30 00:00:00 +00:00
parent f2eb9f85b9
commit c678acd3a2
3 changed files with 27 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
compiler/rustc_mir_transform/src/lib.rs
View File

@@ -616,13 +616,10 @@ fn promoted_mir(tcx: TyCtxt<'_>, def: LocalDefId) -> &IndexVec<Promoted, Body<'_
return tcx.arena.alloc(IndexVec::new());
}
let tainted_by_errors = tcx.mir_borrowck(def).tainted_by_errors;
tcx.ensure_with_value().mir_borrowck(def);
let mut promoted = tcx.mir_promoted(def).1.steal();
for body in &mut promoted {
if let Some(error_reported) = tainted_by_errors {
body.tainted_by_errors = Some(error_reported);
}
run_analysis_to_runtime_passes(tcx, body);
}