separate compilation frame

[Ken Goldman]

In emacs 23.1.1, my *compilation* window goes into a separate frame. 
next-error goes to the line of source in a different frame.

In 24.5.1, the compilation window goes into a split frame.  Even when I 
unsplit the frame, next-error splits it again.

How do I get the emacs 23 behavior - a single compilation frame that 
never splits?

I've seen people post elisp code to get the 23 behavior, but my 
intuition is that the customization is already there somewhere, and the 
default just changed from 23 to 24.