Disable the profiler when a debugger is attached

runtime/vm/thread_interrupter.cc

Index: runtime/vm/thread_interrupter.cc
diff --git a/runtime/vm/thread_interrupter.cc b/runtime/vm/thread_interrupter.cc
index 0ad9ead78a78515ad8db21d12bffd6bca09eacf7..0372f68bcf3b44b79e4ef72a21d4e72ff27eda5a 100644
--- a/runtime/vm/thread_interrupter.cc
+++ b/runtime/vm/thread_interrupter.cc
@@ -70,8 +70,17 @@ void ThreadInterrupter::InitOnce() {
 
 void ThreadInterrupter::Startup() {
   ASSERT(initialized_);
+  if (IsDebuggerAttached()) {
+    MonitorLocker shutdown_ml(monitor_);
+    shutdown_ = true;
+    if (FLAG_trace_thread_interrupter) {
+      OS::PrintErr(
+          "ThreadInterrupter disabled because a debugger is attached.\n");
+    }
+    return;
+  }
   if (FLAG_trace_thread_interrupter) {
-    OS::Print("ThreadInterrupter starting up.\n");
+    OS::PrintErr("ThreadInterrupter starting up.\n");
   }
   ASSERT(interrupter_thread_id_ == OSThread::kInvalidThreadJoinId);
   {
@@ -83,7 +92,7 @@ void ThreadInterrupter::Startup() {
   }
   ASSERT(interrupter_thread_id_ != OSThread::kInvalidThreadJoinId);
   if (FLAG_trace_thread_interrupter) {
-    OS::Print("ThreadInterrupter running.\n");
+    OS::PrintErr("ThreadInterrupter running.\n");
   }
 }
 
@@ -100,7 +109,7 @@ void ThreadInterrupter::Shutdown() {
     shutdown_ml.Notify();
     ASSERT(initialized_);
     if (FLAG_trace_thread_interrupter) {
-      OS::Print("ThreadInterrupter shutting down.\n");
+      OS::PrintErr("ThreadInterrupter shutting down.\n");
     }
   }
 
@@ -110,7 +119,7 @@ void ThreadInterrupter::Shutdown() {
   interrupter_thread_id_ = OSThread::kInvalidThreadJoinId;
 
   if (FLAG_trace_thread_interrupter) {
-    OS::Print("ThreadInterrupter shut down.\n");
+    OS::PrintErr("ThreadInterrupter shut down.\n");
   }
 }
 
@@ -149,7 +158,7 @@ void ThreadInterrupter::ThreadMain(uword parameters) {
   ASSERT(initialized_);
   InstallSignalHandler();
   if (FLAG_trace_thread_interrupter) {
-    OS::Print("ThreadInterrupter thread running.\n");
+    OS::PrintErr("ThreadInterrupter thread running.\n");
   }
   {
     // Signal to main thread we are ready.
@@ -215,7 +224,7 @@ void ThreadInterrupter::ThreadMain(uword parameters) {
   }
   RemoveSignalHandler();
   if (FLAG_trace_thread_interrupter) {
-    OS::Print("ThreadInterrupter thread exiting.\n");
+    OS::PrintErr("ThreadInterrupter thread exiting.\n");
   }
   {
     // Signal to main thread we are exiting.