clang format

src/aion/Tracer.hh

 #pragma once
 
-#include <string>
 #include <cstdint>
+#include <string>
 #include <thread>
 
 #ifdef _MSC_VER
@@ -134,7 +134,7 @@ void write_summary_csv(std::string const& filename);
 void write_collapsed_stack(std::string const& filename);
 /// Json file for use with https://github.com/jlfwong/speedscope
 /// see https://github.com/jlfwong/speedscope/wiki/Importing-from-custom-sources
-void write_speedscope_json(std::string const& filename);
+void write_speedscope_json(std::string const& filename = "speedscope.json");
 /// writes various output formats to a given directory
 /// NOTE: does nothing if directory does not exist
 void write_dir(std::string const& path);