From 32133999aee3f47634be5497b14083935e2c38f7 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Sat, 26 Jul 2025 00:03:25 +0000
Subject: [PATCH] Don't loop if there are no pending obligations

---
 compiler/rustc_trait_selection/src/solve/fulfill.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs
index 3ce0f02551244..b6d4c2da4923f 100644
--- a/compiler/rustc_trait_selection/src/solve/fulfill.rs
+++ b/compiler/rustc_trait_selection/src/solve/fulfill.rs
@@ -118,6 +118,10 @@ impl<'tcx> ObligationStorage<'tcx> {
             );
         })
     }
+
+    fn num_pending(&self) -> usize {
+        self.pending.len()
+    }
 }
 
 impl<'tcx, E: 'tcx> FulfillmentCtxt<'tcx, E> {
@@ -181,6 +185,9 @@ where
 
     fn select_where_possible(&mut self, infcx: &InferCtxt<'tcx>) -> Vec<E> {
         assert_eq!(self.usable_in_snapshot, infcx.num_open_snapshots());
+        if self.obligations.num_pending() == 0 {
+            return vec![];
+        }
         let mut errors = Vec::new();
         loop {
             let mut any_changed = false;