rust/tests/ui/borrowck/tainted-promoteds.rs
Tomasz Miąsko c678acd3a2 Leave promoteds untainted by errors when borrowck fails
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.
2023-04-30 23:57:47 +02:00

12 lines
351 B
Rust

// Regression test for issue #110856, where a borrowck error for a MIR tainted
// all promoteds within. This in turn generated a spurious "erroneous constant
// used" note when trying to evaluate a promoted.
pub fn f() -> u32 {
let a = 0;
a = &0 * &1 * &2 * &3;
//~^ ERROR: cannot assign twice to immutable variable
a
}
fn main() {}