GNU bug report logs - #11604
USE_LISP_UNION_TYPE + USE_LSB_TAG cleanup.

Previous Next

Full log

Message #17 received at 11604 <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 11604 <at> debbugs.gnu.org
Subject: Re: bug#11604: USE_LISP_UNION_TYPE + USE_LSB_TAG cleanup.
Date: Sat, 02 Jun 2012 23:50:07 -0700

On 06/02/2012 12:31 AM, Eli Zaretskii wrote:
> why did you change DECL_ALIGN to DCL_ALIGN?

A typo.  It didn't prevent compilation on my platform.  Thanks for
pointing it out; the revised patch will fix this.

>> +	(union Lisp_Object): Don't worry about WORDS_BIGENDIAN; the
>> +	code works fine either way, and efficiency is not a concern here.
>
> why isn't efficiency a concern?

Because the union type is for debugging, not for production.
It's used mostly to make sure that (for example) one doesn't
mistakenly write "x = y" when one meant to write "x = XINT (y)".
I'll reword the ChangeLog entry to make it clearer.

>> +	(LISP_MAKE_RVALUE, make_number) [USE_LISP_UNION_TYPE]:
>> +	Use an inline function on all platforms, since this is simpler and
>> +	'static inline' (via gnulib) is portable now.
>
> I still see one instance of LISP_MAKE_RVALUE as a macro in lisp.h:

The ChangeLog entry is only about the USE_LISP_UNION_TYPE case, not
the case you noticed.  I'll reword this for clarity.

> Also, which parts of gnulib make 'static inline' portable?  If it
> isn't in a part that is used by the MS-Windows port, the MSVC build is
> still being screwed by these changes.

Mostly, it's the AC_C_INLINE stuff in m4/*.  'static inline' been used
for some time in Emacs, and it works just fine with the MSVC build.
I'll reword the ChangeLog entry to remove the distracting mention of
gnulib.

> The following changes are not mentioned in the log entry:

They are mentioned here:

	(XSET) [USE_LISP_UNION_TYPE]: Don't overparenthesize.

> What was the reason for removing this comment:

Please see Bug#11617, which I just now filed.  I will restore that
comment in the revised patch, as it's now an independent issue.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.