During LineCallback, GetLineNumber() is returning 0 for line number

As the title says, during a LineCallback when calling GetLineNumber() on the context, it's returning 0 for a line number while filling in the section with a legitimate section name. I suspect this is a constructor call for the script class contained in the script section it references. Is there a way to know for sure whether this represents execution inside a script class constructor? It'd be great if script class constructors had actual line numbers represented by GetLineNumber().

For context, I've built a simple sampling profiler that uses the LineCallback to collect the last executed section …