diff options
Diffstat (limited to 'tests/ui/never_type/never-value-fallback-issue-66757.rs')
-rw-r--r-- | tests/ui/never_type/never-value-fallback-issue-66757.rs | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/tests/ui/never_type/never-value-fallback-issue-66757.rs b/tests/ui/never_type/never-value-fallback-issue-66757.rs new file mode 100644 index 000000000..fc6fe6eb5 --- /dev/null +++ b/tests/ui/never_type/never-value-fallback-issue-66757.rs @@ -0,0 +1,31 @@ +// Regression test for #66757 +// +// Test than when you have a `!` value (e.g., the local variable +// never) and an uninferred variable (here the argument to `From`) it +// doesn't fallback to `()` but rather `!`. +// +// revisions: nofallback fallback +//[fallback] run-pass +//[nofallback] check-fail + +#![feature(never_type)] + +#![cfg_attr(fallback, feature(never_type_fallback))] + +struct E; + +impl From<!> for E { + fn from(_: !) -> E { + E + } +} + +#[allow(unreachable_code)] +#[allow(dead_code)] +#[allow(unused_must_use)] +fn foo(never: !) { + <E as From<!>>::from(never); // Ok + <E as From<_>>::from(never); //[nofallback]~ ERROR trait bound `E: From<()>` is not satisfied +} + +fn main() { } |