Debug-only logging code to track down bug 469514.

r=ted

xpcom/io/nsStreamUtils.cpp

@@ -98,6 +98,11 @@ public:
             mTarget->Dispatch(this, NS_DISPATCH_NORMAL);
         if (NS_FAILED(rv)) {
             NS_WARNING("Dispatch failed");
+#ifdef DEBUG
+            (void)fprintf(stdout,
+                          "### mTarget (%p) may not be accepting events!\n",
+                          mTarget);
+#endif
             return NS_ERROR_FAILURE;
         }
 
@@ -177,6 +182,11 @@ public:
             mTarget->Dispatch(this, NS_DISPATCH_NORMAL);
         if (NS_FAILED(rv)) {
             NS_WARNING("PostEvent failed");
+#ifdef DEBUG
+            (void)fprintf(stdout,
+                          "### mTarget (%p) may not be accepting events!\n",
+                          mTarget);
+#endif
             return NS_ERROR_FAILURE;
         }
 

xpcom/threads/nsThreadManager.cpp

@@ -43,6 +43,21 @@
 #include "nsAutoPtr.h"
 #include "nsAutoLock.h"
 
+#ifdef DEBUG
+#include "nsStackWalk.h"
+
+static void
+thread_stack_callback(void *aPC, void *)
+{
+  char buf[1024];
+  nsCodeAddressDetails details;
+
+  (void)NS_DescribeCodeAddress(aPC, &details);
+  (void)NS_FormatCodeAddressDetails(aPC, &details, buf, sizeof(buf));
+  (void)fprintf(stdout, buf);
+}
+#endif
+
 typedef nsTArray< nsRefPtr<nsThread> > nsThreadArray;
 
 //-----------------------------------------------------------------------------
@@ -232,6 +247,11 @@ nsThreadManager::NewThread(PRUint32 creationFlags, nsIThread **result)
   // At this point, we expect that the thread has been registered in mThread;
   // however, it is possible that it could have also been replaced by now, so
   // we cannot really assert that it was added.
+#ifdef DEBUG
+  (void)fprintf(stdout, "### Creating thread with address %p\n", thr);
+  (void)NS_StackWalk(thread_stack_callback, 0, nsnull);
+  (void)fprintf(stdout, "\n\n");
+#endif
 
   *result = thr;
   return NS_OK;