bug#46818: leim bootstrap: Variable binding depth exceeds max-specpdl-size

[Glenn Morris]

Package: emacs
Version: 28.0.50

When building in a completely clean tree (new checkout or make extraclean)
at rev a4d7235f1a, I see the following errors when building the leim files:

  GEN      ../lisp/language/pinyin.el
  GEN      ../lisp/leim/leim-list.el
Eager macro-expansion failure: (error "Variable binding depth exceeds
  max-specpdl-size")

  [...]
  INFO     Processing OKURI-NASI entries...done
  Eager macro-expansion failure: (error "Variable binding depth exceeds
  max-specpdl-size")

These issues don't seem to be present at rev 6bf56a; ref
https://hydra.nixos.org/build/137524247