I used that B compiler on a Honeywell GCOS mainframe in the late 1970s and early 1980s. It was a blindingly fast compiler written at University of Waterloo by a Brazilian named Reinaldo Braga. Still available from a Canadian company named Thinkage. The Honeywell 6000 series used 36 bit words.
C was needed because the byte-addressed PDP-11 was a bad fit for the word oriented B language. See https://archive.org/details/bstj57-6-1991 for details.