old-style backquotes now generates void macro

[Kan-Ru Chen]

Hi,

Using recently compiled emacs development branch, GNU Emacs 24.0.50.1
(x86_64-pc-linux-gnu, GTK+ Version 2.20.1) of 2010-12-12

Byte compiling following file will produce an error:

,----[ test.el ]
| (defmacro test-macro (rec)
|   (` ((, rec))))
| 
| (defun test nil
|   (test-macro x))
`----

,----[ *Compile-Log* ]
| Compiling file /home/kanru/test.el at Mon Dec 13 11:45:18 2010
| test.el:1:1:Warning: !! The file uses old-style backquotes !!
| This functionality has been obsolete for more than 10 years already
| and will be removed soon.  See (elisp)Backquote in the manual.
| test.el:4:8:Error: Symbol's function definition is void: 
`----

Affected package like APEL and BBDB cannot be compiled now.  Is this
intended to push the phase out of old-style backquotes?

- Kanru