+#ifndef SCOPE_TRACING
+#define ST()
+#define STN(N)
+#else
+#define ST() \
+ ScopeTrace __attribute__((unused)) CONCAT(trace_scope_, __LINE__)(__func__)
+#define STN(N) \
+ ScopeTrace __attribute__((unused)) CONCAT(named_trace_scope_, __LINE__)(#N)
+
+struct ScopeTrace {
+ thread_local static int indent;
+ char const *f{};
+ explicit ScopeTrace(char const *func);
+ ~ScopeTrace();
+};
+#endif
+