From 64704694a40b429f30c2a620c1a899479e0da36e Mon Sep 17 00:00:00 2001
From: Jeremy Schonfeld <jschonfeld@apple.com>
Date: Wed, 15 Jan 2025 12:20:15 -0500
Subject: [PATCH] Fix race condition in __CFStringGetEightBitStringEncoding
 (#5155)

---
 Sources/CoreFoundation/include/ForFoundationOnly.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Sources/CoreFoundation/include/ForFoundationOnly.h b/Sources/CoreFoundation/include/ForFoundationOnly.h
index 5bfea27735..b524163d4c 100644
--- a/Sources/CoreFoundation/include/ForFoundationOnly.h
+++ b/Sources/CoreFoundation/include/ForFoundationOnly.h
@@ -287,8 +287,11 @@ CF_EXPORT CFStringEncoding __CFDefaultEightBitStringEncoding;
 CF_EXPORT CFStringEncoding __CFStringComputeEightBitStringEncoding(void);
 
 CF_INLINE CFStringEncoding __CFStringGetEightBitStringEncoding(void) {
-    if (__CFDefaultEightBitStringEncoding == kCFStringEncodingInvalidId) __CFStringComputeEightBitStringEncoding();
-    return __CFDefaultEightBitStringEncoding;
+    if (__CFDefaultEightBitStringEncoding == kCFStringEncodingInvalidId) {
+        return __CFStringComputeEightBitStringEncoding();
+    } else {
+        return __CFDefaultEightBitStringEncoding;
+    }
 }
 
 enum {