From 60be29bec8734e1455e2833b6cc5f5bfc0e39fa2 Mon Sep 17 00:00:00 2001
From: Santiago Pastorino <spastorino@gmail.com>
Date: Sat, 6 Apr 2024 14:45:48 -0300
Subject: [PATCH] Add a debug asserts call to match_projection_projections to
 ensure invariant

---
 compiler/rustc_trait_selection/src/traits/select/mod.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index aa4ab9c7ee9c6..5e9a28b5cceac 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -1732,6 +1732,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         env_predicate: PolyProjectionPredicate<'tcx>,
         potentially_unnormalized_candidates: bool,
     ) -> ProjectionMatchesProjection {
+        debug_assert_eq!(obligation.predicate.def_id, env_predicate.projection_def_id());
+
         let mut nested_obligations = Vec::new();
         let infer_predicate = self.infcx.instantiate_binder_with_fresh_vars(
             obligation.cause.span,