GNU bug report logs - #25338
[PATCH] Remove local variable with only one usage

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Chris Gregory <czipperz <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Subject: [PATCH] Remove local variable with only one usage
Date: Mon, 02 Jan 2017 13:50:01 -0800

-- 
Chris Gregory

diff --git a/src/term.c b/src/term.c
index c067a86d18..0e8ad60de4 100644
--- a/src/term.c
+++ b/src/term.c
@@ -3426,10 +3426,7 @@ tty_menu_last_menubar_item (struct frame *f)
 
       while (i < ASIZE (items))
 	{
-	  Lisp_Object str;
-
-	  str = AREF (items, i + 1);
-	  if (NILP (str))
+	  if (NILP (AREF (items, i + 1)))
 	    break;
 	  i += 4;
 	}

Message #8 received at 25338 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Chris Gregory <czipperz <at> gmail.com>
Cc: 25338 <at> debbugs.gnu.org
Subject: Re: bug#25338: [PATCH] Remove local variable with only one usage
Date: Sat, 07 Jan 2017 10:26:30 +0200

tags 25338 notabug
close 25338
thanks

> From: Chris Gregory <czipperz <at> gmail.com>
> Date: Mon, 02 Jan 2017 13:50:01 -0800

Thanks.

IMO, we are splitting hair here.  In an optimized build, a compiler
will optimize 'str' and keep the value in a register, so the variable
doesn't matter.  In a non-optimized build, the existence of the
variable allows to look at it in a debugger.  And the loop is small
enough so that an extra variable local to the loop doesn't make it
more complicated.

So I'd rather not make this change.

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