If a function is defined by defun, labels, or flet, then the debugger will print the actual function name after the open parenthesis, like:
Otherwise, the function name is a string, and will be printed in quotes:(STRING-UPCASE "test case" :START 0 :END NIL) ((SETF AREF) #a "for" 1)
This string name is derived from the defmumble form that encloses or expanded into the lambda, or the outermost enclosing form if there is no defmumble.("DEFUN MYFUN" BAR) ("DEFMACRO DO" (DO ((I 0 (1+ I))) ((= I 13))) NIL) ("SETQ *GC-NOTIFY-BEFORE*")