Subject: 26.0.50; Error completing help with nil entries in load-history
From: Yuri D'Elia <[email-masked]>
To: [email-masked]
Cc: Richard Copley <[email-masked]>
Date: Thu, 23 Feb 2017 11:49:11 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

This is a regression in emacs 26. How to reproduce:

(defun test () "" nil) ;; insert text in buffer *scratch*
C-M-x ;; eval-defun (adds an entry to load-history with null file)
C-h f package- TAB ;; crashes

This is caused by `help--loaded-p' not handling nil entries, introduced
in 0c31ff43b6880c84498fbe1f06e1e5809b55e838.