Awk split()/array bug in 7.5

I spotted the following issue, which is also present in FreeBSD.

$ awk -V
awk version 20240122
$ awk 'BEGIN {split("A B C", ABC, " ");for (x in ABC) {print x}}'
2
3
1

FreeBSD 14, awk 20210724:
$ awk 'BEGIN {split("A B C", ABC, " ");for (x in ABC) {print x}}'
2
3
1

Linux, mawk 1.3.4 20200120:
$ awk 'BEGIN {split("A B C", ABC, " ");for (x in ABC) {print x}}'
3
2
1

Jeff