Creator hangs in code completion

My code looks like this:

   QString pattern;
   int index = pattern.lastIndexOf('/');
   if (index == pattern.co

Here I want to do code completion. The combo box opens up, I select "count" and press Return. Afterwards, Creator hangs. The reason is that the while loop at src/plugins/cpptools/cppcompletionassist.cpp:347 starts out with a negative controlling value. In my example, the values are as follows:
toInsert.length() = 5, editor->position() = 21147, basePosition = 21140, resulting in an initial value of -2 for preserveLength. Relevent stack trace attached.