> Could you please point out where does pcase.el uses 'map' in its > source? The error message you quote doesn't reference pcase.el, only > org-bookmark-heading.el, which is not part of Emacs and is not on > ELPA, AFAICT. Apology for the misleading title. `pcase.el' itself doesn't depend on `map.el', nor does it contain `map' pattern in its source. `pcase.el' itself successfully compiles. I encountered the error while trying to byte-compile `org-bookmark-heading.el', which contains a `map' pattern at the following location: https://github.com/alphapapa/org-bookmark-heading/blob/f245c9023df28d6ee545dae4b96a1c237e6965ba/org-bookmark-heading.el#L176 The error vanishes if I add `(eval-when-compile (require 'map))' as in the following PR: https://github.com/alphapapa/org-bookmark-heading/pull/19/files I encountered similar errors in other libraries that contain a `map' pattern inside a `pcase' form. It didn't happen until recently, when I updated Emacs and began to get those errors. > So I wonder where's the place in the core Emacs sources > which causes the problem, and I couldn't find it. I'm probably > missing something. There are some other additional patterns for `pcase'. One of them is `rx' pattern. There is an autoload cookie right above the definition of `(pcase-defmacro rx ...' in `rx.el'. On the other hand, there is no autoload above `(pcase-defmacro map ...' in `map.el'. I think this might be the cause. Is there any reason for not autoloading the `pcase-defmacro` form? Thanks.