http://www.projectoberon.com/ is released and small enough for a book in the dead-trees format.

In case you're not joking, MINIX is much smaller than 100KLOCs.

Check out stats on the kOS/kparc project: https://news.ycombinator.com/item?id=9316091

There is also a more recent example of Arthur Whitney writing a C compiler in <250 lines of C. Remarkable how productive a programmer can be when he chooses not to overcomplicate.

Everything I saw in the link looks like K, not C. Do you have a link to the C compiler done in C language?