Merge "Fix format specifier for TracingBackendId (aka size_t)"
diff --git a/src/tracing/internal/tracing_muxer_impl.cc b/src/tracing/internal/tracing_muxer_impl.cc
index 41da7e6..1d6e2ca 100644
--- a/src/tracing/internal/tracing_muxer_impl.cc
+++ b/src/tracing/internal/tracing_muxer_impl.cc
@@ -2046,7 +2046,7 @@
           return;
         }
 
-        PERFETTO_DLOG("Reconnecting backend %ld for startup tracing",
+        PERFETTO_DLOG("Reconnecting backend %zu for startup tracing",
                       backend_id);
         backend.producer_conn_args.use_producer_provided_smb = true;
         backend.producer->service_->Disconnect();  // Causes a reconnect.