(inside a function or dot script) the exit status of that return
statement should become the exit status of the function (or dot
script) - we were ignoring it,
That is
fn() { while return 7; do return 9; done; return 11; }
should exit with status 7. It was exiting 0.
This is apparently another old ash bug that has been fixed
everywhere else in the past.
Issue pointed out by Martijn Dekker, (fairly obvious) fix borrowed
from FreeBSD, due for return sometime next century.