From 994b58fee7e66c25d4b13a8a95feaff650088301 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Mon, 15 Apr 2024 10:45:37 -0400
Subject: [PATCH] Okay actually check only alias TYPES
---
compiler/rustc_trait_selection/src/traits/wf.rs | 12 +++---------
tests/ui/higher-ranked/well-formed-aliases.rs | 8 ++++++++
tests/ui/higher-ranked/well-formed-aliases.stderr | 12 ++++++++++++
3 files changed, 23 insertions(+), 9 deletions(-)
create mode 100644 tests/ui/higher-ranked/well-formed-aliases.rs
create mode 100644 tests/ui/higher-ranked/well-formed-aliases.stderr
diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs
index f4189ff090204..57efd2996e409 100644
--- a/compiler/rustc_trait_selection/src/traits/wf.rs
+++ b/compiler/rustc_trait_selection/src/traits/wf.rs
@@ -435,12 +435,6 @@ impl<'a, 'tcx> WfPredicates<'a, 'tcx> {
}
}
- /// Pushes the obligations required for an alias (except inherent) to be WF
- /// into `self.out`.
- fn compute_alias_ty(&mut self, data: ty::AliasTy<'tcx>) {
- self.compute_alias_term(data.into());
- }
-
/// Pushes the obligations required for an alias (except inherent) to be WF
/// into `self.out`.
fn compute_alias_term(&mut self, data: ty::AliasTerm<'tcx>) {
@@ -498,7 +492,7 @@ impl<'a, 'tcx> WfPredicates<'a, 'tcx> {
self.out.extend(obligations);
}
- self.compute_projection_args(data.args);
+ data.args.visit_with(self);
}
fn compute_projection_args(&mut self, args: GenericArgsRef<'tcx>) {
@@ -702,8 +696,8 @@ impl<'a, 'tcx> TypeVisitor<TyCtxt<'tcx>> for WfPredicates<'a, 'tcx> {
}
ty::Alias(ty::Projection | ty::Opaque | ty::Weak, data) => {
- self.compute_alias_ty(data);
- return; // Subtree handled by compute_projection.
+ let obligations = self.nominal_obligations(data.def_id, data.args);
+ self.out.extend(obligations);
}
ty::Alias(ty::Inherent, data) => {
self.compute_inherent_projection(data);
diff --git a/tests/ui/higher-ranked/well-formed-aliases.rs b/tests/ui/higher-ranked/well-formed-aliases.rs
new file mode 100644
index 0000000000000..60e013a54bcd5
--- /dev/null
+++ b/tests/ui/higher-ranked/well-formed-aliases.rs
@@ -0,0 +1,8 @@
+trait Trait {
+ type Gat<U: ?Sized>;
+}
+
+fn test<T>(f: for<'a> fn(<&'a T as Trait>::Gat<&'a [str]>)) where for<'a> &'a T: Trait {}
+//~^ ERROR the size for values of type `str` cannot be known at compilation time
+
+fn main() {}
diff --git a/tests/ui/higher-ranked/well-formed-aliases.stderr b/tests/ui/higher-ranked/well-formed-aliases.stderr
new file mode 100644
index 0000000000000..4a6f4e961d995
--- /dev/null
+++ b/tests/ui/higher-ranked/well-formed-aliases.stderr
@@ -0,0 +1,12 @@
+error[E0277]: the size for values of type `str` cannot be known at compilation time
+ --> $DIR/well-formed-aliases.rs:5:52
+ |
+LL | fn test<T>(f: for<'a> fn(<&'a T as Trait>::Gat<&'a [str]>)) where for<'a> &'a T: Trait {}
+ | ^^^^^ doesn't have a size known at compile-time
+ |
+ = help: the trait `Sized` is not implemented for `str`
+ = note: slice and array elements must have `Sized` type
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0277`.