From c20a80092c15c6da5de2e5829be88e2009d5899f Mon Sep 17 00:00:00 2001
From: =?utf8?q?Stefan=20Gr=C3=A4nitz?= <stefan.graenitz@gmail.com>
Date: Wed, 23 Nov 2022 11:19:13 +0100
Subject: [PATCH] [ObjC][ARC] Fix UB in ObjCARCOpt with
 -enable-objc-arc-opts=false

When ObjCARCOpt::run() returned early, Changed and CFGChanged were never initialized. CFGChanged is read unconditionally afterwards. This came up in the course of D137942.
---
 llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp b/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp
index 9834679..d703468 100644
--- a/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp
+++ b/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp
@@ -481,8 +481,8 @@ namespace {
 
   /// The main ARC optimization pass.
 class ObjCARCOpt {
-  bool Changed;
-  bool CFGChanged;
+  bool Changed = false;
+  bool CFGChanged = false;
   ProvenanceAnalysis PA;
 
   /// A cache of references to runtime entry point constants.
-- 
2.7.4