1 files changed, 73 insertions, 0 deletions
diff --git a/src/test/ui/const-generics/generic_const_exprs/issue-82268.rs b/src/test/ui/const-generics/generic_const_exprs/issue-82268.rs
new file mode 100644
index 000000000..d08fc5beb
--- /dev/null
+++ b/src/test/ui/const-generics/generic_const_exprs/issue-82268.rs
@@ -0,0 +1,73 @@
+// build-pass
+
+#![allow(incomplete_features)]
+#![feature(generic_const_exprs)]
+
+trait Collate<Op> {
+    type Pass;
+    type Fail;
+
+    fn collate(self) -> (Self::Pass, Self::Fail);
+}
+
+impl<Op> Collate<Op> for () {
+    type Pass = ();
+    type Fail = ();
+
+    fn collate(self) -> ((), ()) {
+        ((), ())
+    }
+}
+
+trait CollateStep<X, Prev> {
+    type Pass;
+    type Fail;
+    fn collate_step(x: X, prev: Prev) -> (Self::Pass, Self::Fail);
+}
+
+impl<X, P, F> CollateStep<X, (P, F)> for () {
+    type Pass = (X, P);
+    type Fail = F;
+
+    fn collate_step(x: X, (p, f): (P, F)) -> ((X, P), F) {
+        ((x, p), f)
+    }
+}
+
+struct CollateOpImpl<const MASK: u32>;
+trait CollateOpStep {
+    type NextOp;
+    type Apply;
+}
+
+impl<const MASK: u32> CollateOpStep for CollateOpImpl<MASK>
+where
+    CollateOpImpl<{ MASK >> 1 }>: Sized,
+{
+    type NextOp = CollateOpImpl<{ MASK >> 1 }>;
+    type Apply = ();
+}
+
+impl<H, T, Op: CollateOpStep> Collate<Op> for (H, T)
+where
+    T: Collate<Op::NextOp>,
+    Op::Apply: CollateStep<H, (T::Pass, T::Fail)>,
+{
+    type Pass = <Op::Apply as CollateStep<H, (T::Pass, T::Fail)>>::Pass;
+    type Fail = <Op::Apply as CollateStep<H, (T::Pass, T::Fail)>>::Fail;
+
+    fn collate(self) -> (Self::Pass, Self::Fail) {
+        <Op::Apply as CollateStep<H, (T::Pass, T::Fail)>>::collate_step(self.0, self.1.collate())
+    }
+}
+
+fn collate<X, const MASK: u32>(x: X) -> (X::Pass, X::Fail)
+where
+    X: Collate<CollateOpImpl<MASK>>,
+{
+    x.collate()
+}
+
+fn main() {
+    dbg!(collate::<_, 5>(("Hello", (42, ('!', ())))));
+}