From 94a0819fe3a0d679c3042a77bfe6a2afc505daea Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:11:28 +0200 Subject: Adding upstream version 1.66.0+dfsg1. Signed-off-by: Daniel Baumann --- .../ui/higher-rank-trait-bounds/issue-57639.rs | 29 ++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 src/test/ui/higher-rank-trait-bounds/issue-57639.rs (limited to 'src/test/ui/higher-rank-trait-bounds/issue-57639.rs') diff --git a/src/test/ui/higher-rank-trait-bounds/issue-57639.rs b/src/test/ui/higher-rank-trait-bounds/issue-57639.rs new file mode 100644 index 000000000..392e7233b --- /dev/null +++ b/src/test/ui/higher-rank-trait-bounds/issue-57639.rs @@ -0,0 +1,29 @@ +// Regression test for #57639: +// +// In the move to universes, this test stopped working. The problem +// was that when the trait solver was asked to prove `for<'a> T::Item: +// Foo<'a>` as part of WF checking, it wound up "eagerly committing" +// to the where clause, which says that `T::Item: Foo<'a>`, but it +// should instead have been using the bound found in the trait +// declaration. Pre-universe, this used to work out ok because we got +// "eager errors" due to the leak check. +// +// See [this comment on GitHub][c] for more details. +// +// check-pass +// +// [c]: https://github.com/rust-lang/rust/issues/57639#issuecomment-455685861 + +trait Foo<'a> {} + +trait Bar { + type Item: for<'a> Foo<'a>; +} + +fn foo<'a, T>(_: T) +where + T: Bar, + T::Item: Foo<'a>, +{} + +fn main() { } -- cgit v1.2.3