From 9cde4463d4c295b3861369f4edcc1415b3d20cb9 Mon Sep 17 00:00:00 2001
From: Alessandro Decina <alessandro.d@gmail.com>
Date: Thu, 14 Dec 2023 11:41:57 +1100
Subject: [PATCH] v1.16: Initialize LoadedPrograms::latest_root earlier
 (#34432)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

* Fixes BankForks::new_from_banks() not setting the root of LoadedPrograms.

---------

Co-authored-by: Alexander Meißner <AlexanderMeissner@gmx.net>
---
 runtime/src/bank_forks.rs | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/runtime/src/bank_forks.rs b/runtime/src/bank_forks.rs
index 91f2304fd281a4..1404be63640cf8 100644
--- a/runtime/src/bank_forks.rs
+++ b/runtime/src/bank_forks.rs
@@ -175,7 +175,7 @@ impl BankForks {
                 descendants.entry(parent).or_default().insert(*slot);
             }
         }
-        Self {
+        let bank_forks = Self {
             root: Arc::new(AtomicSlot::new(root)),
             banks,
             descendants,
@@ -184,7 +184,17 @@ impl BankForks {
             last_accounts_hash_slot: root,
             in_vote_only_mode: Arc::new(AtomicBool::new(false)),
             highest_slot_at_startup: 0,
-        }
+        };
+        let root_bank = bank_forks
+            .banks
+            .get(&root)
+            .expect("root bank didn't exist in bank_forks");
+        root_bank
+            .loaded_programs_cache
+            .write()
+            .unwrap()
+            .prune(&bank_forks, root);
+        bank_forks
     }
 
     pub fn insert(&mut self, mut bank: Bank) -> Arc<Bank> {