Much to my embarrassment, Bjarne Stroustrup was hanging out in the same BIX conference, and he chewed me out for this - but very politely. Bjarne explained that Cfront was definitely not a preprocessor (which would imply something like the C preprocesssor), but an actual honest-to-goodness compiler that just happened to have C as its compilation target.
Now if we could only get the younger generation to abandon that horrible "transpiler" word and call things by their right name: a compiler!