This was awarded "Best of Show - abuse of libc" at the time[0]. See also the judges' remarks[1]:

This program consists of a single printf(3) statement wrapped in a while loop. You would not think that this would amount to much, but you would be very, very wrong. A clue to what is happening and how this works is encoded in the ASCII art of the program source.

[0] https://www.ioccc.org/2020/index.html

[1] https://www.ioccc.org/2020/carlini/index.html

Alex: "Its primary purpose is to serve as The One True Debugger."

(It has certainly served me well.)