Fix binary path extraction and defer benchmark compile error

- Use BENCHMARK_BINARY= marker for reliable binary path extraction
  instead of fragile tail -1 (PlatformIO can print warnings after path)
- Fix Scheduler_Defer: defer() is protected on Component, use
  set_timeout(delay=0) directly on Scheduler instead

.github/workflows/ci.yml

@@ -332,8 +332,8 @@ jobs:
         run: |
           . venv/bin/activate
           export BENCHMARK_LIB_CONFIG=$(python script/setup_codspeed_lib.py)
-          # --build-only prints the binary path as the last line of stdout
-          BINARY=$(script/cpp_benchmark.py --all --build-only | tail -1)
+          # --build-only prints BENCHMARK_BINARY=<path> to stdout
+          BINARY=$(script/cpp_benchmark.py --all --build-only | grep '^BENCHMARK_BINARY=' | tail -1 | cut -d= -f2-)
           echo "binary=$BINARY" >> $GITHUB_OUTPUT
 
       - name: Run CodSpeed benchmarks

script/test_helpers.py

@@ -389,7 +389,7 @@ def build_and_run(
         return exit_code
 
     if build_only:
-        print(program_path)
+        print(f"BENCHMARK_BINARY={program_path}")
         return EXIT_OK
 
     # Run the binary

tests/benchmarks/core/bench_scheduler.cpp

@@ -111,16 +111,20 @@ static void Scheduler_SetInterval(benchmark::State &state) {
 }
 BENCHMARK(Scheduler_SetInterval);
 
-// --- Scheduler: defer registration ---
+// --- Scheduler: defer registration (set_timeout with delay=0) ---
 
 static void Scheduler_Defer(benchmark::State &state) {
+  Scheduler scheduler;
   Component dummy_component;
 
+  // defer() is Component::defer which calls set_timeout(delay=0).
+  // Call set_timeout directly since defer() is protected.
   for (auto _ : state) {
     for (int i = 0; i < kInnerIterations; i++) {
-      dummy_component.defer(static_cast<uint32_t>(i % 5), []() {});
+      scheduler.set_timeout(&dummy_component, static_cast<uint32_t>(i % 5), 0, []() {});
     }
-    benchmark::DoNotOptimize(dummy_component);
+    scheduler.process_to_add();
+    benchmark::DoNotOptimize(scheduler);
   }
   state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }