diff --git a/tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.next.stderr b/tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.next.stderr new file mode 100644 index 00000000000..14a3d5e178d --- /dev/null +++ b/tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.next.stderr @@ -0,0 +1,9 @@ +error[E0284]: type annotations needed: cannot satisfy `for<'a> <_ as Trait<'a>>::Assoc <: >::Assoc` + --> $DIR/rigid-equate-projections-in-higher-ranked-fn-signature.rs:27:50 + | +LL | let _: for<'a> fn(<_ as Trait<'a>>::Assoc) = foo::(); + | ^^^^^^^^^^ cannot satisfy `for<'a> <_ as Trait<'a>>::Assoc <: >::Assoc` + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0284`. diff --git a/tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.rs b/tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.rs new file mode 100644 index 00000000000..10dbc2a4a82 --- /dev/null +++ b/tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.rs @@ -0,0 +1,30 @@ +//@ revisions: current next +//@[current] check-pass +//@[next] compile-flags: -Znext-solver +//@[next] check-fail +//@ ignore-compare-mode-next-solver (explicit revisions) + +/// This triggers an ICE with (and without) `--emit metadata` using the old +/// trait solver: +/// ``` +/// rustc +nightly-2023-01-09 \ +/// tests/ui/higher-ranked/trait-bounds/rigid-equate-projections-in-higher-ranked-fn-signature.rs +/// ``` +/// The ICE was unknowingly fixed by +/// in `nightly-2023-01-10`. +/// This is a regression test for that fixed ICE. For the next solver we simply +/// make sure there is a compiler error. + +trait Trait<'a> { + type Assoc; +} + +fn foo Trait<'a>>() -> for<'a> fn(>::Assoc) { + todo!() +} + +fn bar Trait<'a>>() { + let _: for<'a> fn(<_ as Trait<'a>>::Assoc) = foo::(); //[next]~ ERROR type annotations needed +} + +fn main() {}