; Merge from origin/emacs-27

The following commits were skipped:

1e09364d67 ; Mark Bug#29799 tests as failing since we reverted the fix
de1b33f5a8 Revert "cl-loop: Calculate the array length just once"
caf155c463 Revert "cl-loop: Add missing guard condition"
79e133da03 Revert "Refix conditional step clauses in cl-loop"