From 10fa33441fa64a55ac1ccceaefca624ecd05b7d0 Mon Sep 17 00:00:00 2001
From: tiif <pekyuan@gmail.com>
Date: Sat, 8 Nov 2025 16:14:54 +0000
Subject: [PATCH] Drop environment when evaluating const without generic
 parameters

---
 compiler/rustc_trait_selection/src/traits/mod.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs
index 308d533e6899..6032bcacec6a 100644
--- a/compiler/rustc_trait_selection/src/traits/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/mod.rs
@@ -635,9 +635,10 @@ pub fn try_evaluate_const<'tcx>(
                         return Err(EvaluateConstErr::HasGenericsOrInfers);
                     }
 
-                    let typing_env = infcx
-                        .typing_env(tcx.erase_and_anonymize_regions(param_env))
-                        .with_post_analysis_normalized(tcx);
+                    // Since there is no generic parameter, we can just drop the environment
+                    // to prevent query cycle.
+                    let typing_env = infcx.typing_env(ty::ParamEnv::empty());
+
                     (uv.args, typing_env)
                 }
             };