[compiler-rt] [NFC][tsan] Use the result of placement new (PR #86341)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: Vitaly Buka (vitalybuka)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/86341.diff


1 Files Affected:

- (modified) compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp (+1-2) 


``````````diff
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp b/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp
index 77488f84328542..06c34a2e438388 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp
@@ -200,9 +200,8 @@ void ThreadStart(ThreadState *thr, Tid tid, tid_t os_id,
 }
 
 void ThreadContext::OnStarted(void *arg) {
-  thr = static_cast<ThreadState *>(arg);
   DPrintf("#%d: ThreadStart\n", tid);
-  new (thr) ThreadState(tid);
+  thr = new (arg) ThreadState(tid);
   if (common_flags()->detect_deadlocks)
     thr->dd_lt = ctx->dd->CreateLogicalThread(tid);
   thr->tctx = this;

``````````

</details>


https://github.com/llvm/llvm-project/pull/86341