[llvm] [benchmark] Fix -Wunused-but-set-variable warning in basic_test (PR #213637)

[via llvm-commits]

https://github.com/zhangweize9-cyber updated https://github.com/llvm/llvm-project/pull/213637

>From 1cc83cdda72d30dd4f1e71be2383ef536f7c20e3 Mon Sep 17 00:00:00 2001
From: zhangweize9-cyber <225503200+zhangweize9-cyber at users.noreply.github.com>
Date: Mon, 3 Aug 2026 17:36:07 +0800
Subject: [PATCH] [benchmark] Use [[maybe_unused]] to silence unused variable
 warning in basic_test

---
 third-party/benchmark/test/basic_test.cc | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/third-party/benchmark/test/basic_test.cc b/third-party/benchmark/test/basic_test.cc
index 068cd98476c6f..71302146af03a 100644
--- a/third-party/benchmark/test/basic_test.cc
+++ b/third-party/benchmark/test/basic_test.cc
@@ -147,7 +147,7 @@ BENCHMARK(BM_RangedFor);
 template <typename T>
 void BM_OneTemplateFunc(benchmark::State& state) {
   auto arg = state.range(0);
-  T sum = 0;
+  [[maybe_unused]] T sum = 0;
   for (auto _ : state) {
     sum += static_cast<T>(arg);
   }
@@ -158,8 +158,8 @@ BENCHMARK(BM_OneTemplateFunc<double>)->Arg(1);
 template <typename A, typename B>
 void BM_TwoTemplateFunc(benchmark::State& state) {
   auto arg = state.range(0);
-  A sum = 0;
-  B prod = 1;
+  [[maybe_unused]] A sum = 0;
+  [[maybe_unused]] B prod = 1;
   for (auto _ : state) {
     sum += static_cast<A>(arg);
     prod *= static_cast<B>(arg);