diff --git a/mozilla/htmlparser/tests/outsinks/Convert.cpp b/mozilla/htmlparser/tests/outsinks/Convert.cpp
index 9ebb7113bbe..81929d9671a 100644
--- a/mozilla/htmlparser/tests/outsinks/Convert.cpp
+++ b/mozilla/htmlparser/tests/outsinks/Convert.cpp
@@ -74,7 +74,12 @@ Compare(nsString& str, nsString& aFileName)
   if (str == inString)
     return 0;
   else
+  {
+    char* cstr = str.ToNewCString();
+    printf("Comparison failed:\n-----\n%s\n-----\n", cstr);
+    Recycle(cstr);
     return 1;
+  }
 }
 
 //----------------------------------------------------------------------
diff --git a/mozilla/parser/htmlparser/tests/outsinks/Convert.cpp b/mozilla/parser/htmlparser/tests/outsinks/Convert.cpp
index 9ebb7113bbe..81929d9671a 100644
--- a/mozilla/parser/htmlparser/tests/outsinks/Convert.cpp
+++ b/mozilla/parser/htmlparser/tests/outsinks/Convert.cpp
@@ -74,7 +74,12 @@ Compare(nsString& str, nsString& aFileName)
   if (str == inString)
     return 0;
   else
+  {
+    char* cstr = str.ToNewCString();
+    printf("Comparison failed:\n-----\n%s\n-----\n", cstr);
+    Recycle(cstr);
     return 1;
+  }
 }
 
 //----------------------------------------------------------------------