Found a better solution to the Traub&Miles problem: Declaring the variables _a and _b as volatile and using them to store temporary values avoids the "+FLT_MIN" or "+DBL_MIN" solution to be optimised away by the compiler.
The solution I have put now should perform fairly fast and yet
lead to only minimal distortions of the model. We could offer the if-statement based solution as a "TraubMiles_pedantic" version.