diff --git a/script/cpp_benchmark.py b/script/cpp_benchmark.py
index 92faa05819a..5080a9fec74 100755
--- a/script/cpp_benchmark.py
+++ b/script/cpp_benchmark.py
@@ -26,12 +26,11 @@ CORE_BENCHMARKS_DIR: Path = Path(root_path) / "tests" / "benchmarks" / "core"
 STUBS_DIR: Path = Path(root_path) / "tests" / "benchmarks" / "stubs"
 
 PLATFORMIO_OPTIONS = {
-    "build_unflags": [
-        "-Os",  # remove default size-opt
-    ],
     "build_flags": [
-        "-O2",  # optimize for speed (CodSpeed recommends RelWithDebInfo)
+        "-Os",  # match firmware optimization level (detects inlining regressions)
         "-g",  # debug symbols for profiling
+        "-ffunction-sections",  # required for dead-code stripping with -Os
+        "-fdata-sections",  # required for dead-code stripping with -Os
         "-DUSE_BENCHMARK",  # disable WarnIfComponentBlockingGuard in finish()
         f"-I{STUBS_DIR}",  # stub headers for ESP32-only components
     ],