[BUG] Agenda view fails with rx error in org-at-timestamp-p

[Christian Moe <mail@christianmoe.com>]

Hi,

After updating to Org mode version 9.5.3-g69c588 via Elpa on Emacs
26.3, my Org Agenda view fails with the following backtrace:

Debugger entered--Lisp error: (error "rx form ‘regexp’ requires args satisfying ‘stringp’")
  signal(error ("rx form ‘regexp’ requires args satisfying ‘stringp’"))
  error("rx form `%s' requires args satisfying `%s'" regexp stringp)
  rx-check((regexp org-ts-regexp3))
  rx-regexp((regexp org-ts-regexp3))
  rx-form((regexp org-ts-regexp3) |)
  #f(compiled-function (x) #<bytecode 0x172a129>)((regexp org-ts-regexp3))
  mapconcat(#f(compiled-function (x) #<bytecode 0x172a129>) ((regexp org-ts-regexp3) (regexp org-element--timestamp-regexp)) "\\|")
  rx-or((or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp)))
  rx-form((or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp)))
  rx-to-string((or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp)) t)
  #f(compiled-function (&rest regexps) #<bytecode 0x16fa711>)((or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp)))
  (rx (or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp)))
  (if (eq extended (quote agenda)) (rx (or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp))) org-ts-regexp3)
  (if extended (if (eq extended (quote agenda)) (rx (or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp))) org-ts-regexp3) org-ts-regexp2)
  (let* ((regexp (if extended (if (eq extended (quote agenda)) (rx (or (regexp org-ts-regexp3) (regexp org-element--timestamp-regexp))) org-ts-regexp3) org-ts-regexp2)) (pos (point)) (match\? (let ((boundaries (org-in-regexp regexp))) (save-match-data (cond ((null boundaries) nil) ((eq extended ...) t) (t (or ... ...))))))) (cond ((not match\?) nil) ((= pos (match-beginning 0)) (quote bracket)) ((= pos (1- (match-end 0))) (quote bracket)) ((= pos (match-end 0)) (quote after)) ((org-pos-in-match-range pos 2) (quote year)) ((org-pos-in-match-range pos 3) (quote month)) ((org-pos-in-match-range pos 7) (quote hour)) ((org-pos-in-match-range pos 8) (quote minute)) ((or (org-pos-in-match-range pos 4) (org-pos-in-match-range pos 5)) (quote day)) ((and (or (match-end 8) (match-end 5)) (> pos (or (match-end 8) (match-end 5))) (< pos (match-end 0))) (- pos (or (match-end 8) (match-end 5)))) (t (quote day))))
  org-at-timestamp-p(agenda)
  org-agenda-get-timestamps(nil)
  org-agenda-get-day-entries("/home/cm/org/pro.org" (4 18 2022) :deadline :scheduled :timestamp :sexp)
  apply(org-agenda-get-day-entries "/home/cm/org/pro.org" (4 18 2022) (:deadline :scheduled :timestamp :sexp))
  org-agenda-list(nil)
  funcall-interactively(org-agenda-list nil)
  call-interactively(org-agenda-list)
  org-agenda(nil)
  funcall-interactively(org-agenda nil)
  call-interactively(org-agenda nil nil)
  command-execute(org-agenda)

Yours,
Christian