diff --git a/test/format-test.cc b/test/format-test.cc
index c8293258cbef2..7f91e3075e9a2 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1772,8 +1772,7 @@ TEST(format_test, line_buffering) {
   auto read_end = pipe.read_end.fdopen("r");
   std::thread reader([&]() {
     int n = 0;
-    int result = fscanf(read_end.get(), "%d", &n);
-    (void)result;
+    (void)fscanf(read_end.get(), "%d", &n);
     EXPECT_EQ(n, 42);
     cv.notify_one();
   });