From 7b30d3507fa7a45ff0cbdb7d3e775cf0a4be0701 Mon Sep 17 00:00:00 2001
From: Alexander Aprelev <aam@google.com>
Date: Wed, 27 Aug 2025 15:16:10 -0700
Subject: [PATCH] [vm/shared] Ensure field initialization uses store-release
 semantic for updating shared fields.

Fixes https://github.com/dart-lang/sdk/issues/61367
TEST=ci tsan

Change-Id: I8e3e6fa1e4f4a799f19eca298be9e37c972b3343
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/447442
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
---
 runtime/vm/compiler/stub_code_compiler.cc | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/runtime/vm/compiler/stub_code_compiler.cc b/runtime/vm/compiler/stub_code_compiler.cc
index 300b7262b6b..23a4280a33b 100644
--- a/runtime/vm/compiler/stub_code_compiler.cc
+++ b/runtime/vm/compiler/stub_code_compiler.cc
@@ -137,12 +137,20 @@ void StubCodeCompiler::GenerateInitLateStaticFieldStub(bool is_final,
   Label throw_exception;
   if (is_final) {
     __ Comment("Checking that initializer did not set late final field");
-    __ LoadFromOffset(kScratchReg, kAddressReg, 0);
+    if (is_shared) {
+      __ LoadAcquireFromOffset(kScratchReg, kAddressReg, 0);
+    } else {
+      __ LoadFromOffset(kScratchReg, kAddressReg, 0);
+    }
     __ CompareObject(kScratchReg, SentinelObject());
     __ BranchIf(NOT_EQUAL, &throw_exception);
   }
 
-  __ StoreToOffset(kResultReg, kAddressReg, 0);
+  if (is_shared) {
+    __ StoreReleaseToOffset(kResultReg, kAddressReg, 0);
+  } else {
+    __ StoreToOffset(kResultReg, kAddressReg, 0);
+  }
   __ LeaveStubFrame();
   __ Ret();