bug#21828: 24.4; copy-abbrev-table fails

[Eli Zaretskii]

> From: Lee B <lboc.home@gmail.com>
> Date: Wed, 04 Nov 2015 21:34:27 +0900
> 
> Working on some tests for abbrev.el, I came across the following:
> 
> 1. Start emacs -Q
> 2. In scratch buffer, evaluate (list-abbrevs) to get abbrev tables.
> 3. Pick an abbrev table (eg. in my case awk-mode-abbrev-table) and
> evaluate it:
> 
> awk-mode-abbrev-table
> [## 0 0 0 0 0 0 0 0 0 0 0 ...]
> 
> 4. Evaluate (copy-abbrev-table awk-mode-abbrev-table). Generates error
> with backtrace:
> 
> Debugger entered--Lisp error: (wrong-type-argument number-or-marker-p nil)
>   define-abbrev([## 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
> 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...] "" nil nil)

Thanks, fixed.

(This bug was there ever since we rewrote abbrev.c in Lisp 8 years
ago.)