- Write the coverage data to a file instead of printing to stdout.

runtime/vm/os_linux.cc

Index: runtime/vm/os_linux.cc
===================================================================
--- runtime/vm/os_linux.cc	(revision 27712)
+++ runtime/vm/os_linux.cc	(working copy)
@@ -129,10 +129,10 @@
     if (file_open == NULL) {
       return;
     }
-    const char* format = "/tmp/perf-%ld.map";
+    const char* format = "/tmp/perf-%"Pd".map";
     intptr_t pid = getpid();
     intptr_t len = OS::SNPrint(NULL, 0, format, pid);
-    char* filename = new char[len + 1];
+    char* filename = Isolate::Current()->current_zone()->Alloc<char>(len + 1);
     OS::SNPrint(filename, len + 1, format, pid);
     out_file_ = (*file_open)(filename, true);
   }
@@ -273,6 +273,11 @@
 }
 
 
+intptr_t OS::ProcessId() {
+  return static_cast<intptr_t>(getpid());
+}
+
+
 static bool LocalTime(int64_t seconds_since_epoch, tm* tm_result) {
   time_t seconds = static_cast<time_t>(seconds_since_epoch);
   if (seconds != seconds_since_epoch) return false;