[llvm] [ADT] Add back load bearing <vector> include (PR #225872)

[Luke Lau via llvm-commits]

https://github.com/lukel97 created https://github.com/llvm/llvm-project/pull/225872

This should fix the build failures reported in https://lab.llvm.org/buildbot/#/builders/25/builds/19816, looks like other places were relying on it transitively

>From 2f4f7c1d6b015e1245bebe4b5aa04fe9a8986bab Mon Sep 17 00:00:00 2001
From: Luke Lau <luke at igalia.com>
Date: Wed, 23 Sep 2026 18:54:24 +0100
Subject: [PATCH] [ADT] Add back load bearing <vector> include

This should fix the build failures reported in https://lab.llvm.org/buildbot/#/builders/25/builds/19816, looks like other places were relying on it transitively
---
 llvm/include/llvm/ADT/DepthFirstIterator.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/llvm/include/llvm/ADT/DepthFirstIterator.h b/llvm/include/llvm/ADT/DepthFirstIterator.h
index 97febd9777cc1..80395027bff0e 100644
--- a/llvm/include/llvm/ADT/DepthFirstIterator.h
+++ b/llvm/include/llvm/ADT/DepthFirstIterator.h
@@ -42,6 +42,7 @@
 #include <optional>
 #include <type_traits>
 #include <utility>
+#include <vector>
 
 namespace llvm {