GNU bug report logs - #23758
25.1.50; Bogus warning from -Wwrite-strings

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 23758 in the body.
You can then email your comments to 23758 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

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

From: Ken Brown <kbrown <at> cornell.edu>
To: bug-gnu-emacs <at> gnu.org
Subject: 25.1.50; Bogus warning from -Wwrite-strings
Date: Sun, 12 Jun 2016 15:56:32 -0400

I'm getting an "assignment discards ‘const’ qualifier from pointer
target type" warning in the Cygwin-w32 build because of the following
code in w32fns.c:

char *type_CtrlAlt = NULL;
[...]
type_CtrlAlt = "bB";

This warning goes away if I remove -Wwrite-strings from the enabled 
compiler warnings.  Is this a compiler bug, or is there really something 
wrong with the code above that should warrant a warning?


In GNU Emacs 25.1.50.11 (x86_64-unknown-cygwin)
 of 2016-06-12 built on moufang
Repository revision: eacdc9eb6c89346fb72535632a1c65f6483b639f
Windowing system distributor 'Microsoft Corp.', version 10.0.10586

Configured using:
 'configure 'CFLAGS=-g3 -O0' --with-w32'

Message #8 received at 23758 <at> debbugs.gnu.org (full text, mbox):

From: Noam Postavsky <npostavs <at> users.sourceforge.net>
To: Ken Brown <kbrown <at> cornell.edu>
Cc: 23758 <at> debbugs.gnu.org
Subject: Re: bug#23758: 25.1.50; Bogus warning from -Wwrite-strings
Date: Sun, 12 Jun 2016 16:01:15 -0400

On Sun, Jun 12, 2016 at 3:56 PM, Ken Brown <kbrown <at> cornell.edu> wrote:
> I'm getting an "assignment discards ‘const’ qualifier from pointer
> target type" warning in the Cygwin-w32 build because of the following
> code in w32fns.c:
>
> char *type_CtrlAlt = NULL;
> [...]
> type_CtrlAlt = "bB";
>
> This warning goes away if I remove -Wwrite-strings from the enabled compiler
> warnings.  Is this a compiler bug, or is there really something wrong with
> the code above that should warrant a warning?

I think the warning is correct, and the code shoud use const char *type_CtrlAlt

Message #13 received at 23758-done <at> debbugs.gnu.org (full text, mbox):

From: Ken Brown <kbrown <at> cornell.edu>
To: Noam Postavsky <npostavs <at> users.sourceforge.net>
Cc: 23758-done <at> debbugs.gnu.org
Subject: Re: bug#23758: 25.1.50; Bogus warning from -Wwrite-strings
Date: Sun, 12 Jun 2016 17:45:09 -0400

On 6/12/2016 4:01 PM, Noam Postavsky wrote:
> On Sun, Jun 12, 2016 at 3:56 PM, Ken Brown <kbrown <at> cornell.edu> wrote:
>> I'm getting an "assignment discards ‘const’ qualifier from pointer
>> target type" warning in the Cygwin-w32 build because of the following
>> code in w32fns.c:
>>
>> char *type_CtrlAlt = NULL;
>> [...]
>> type_CtrlAlt = "bB";
>>
>> This warning goes away if I remove -Wwrite-strings from the enabled compiler
>> warnings.  Is this a compiler bug, or is there really something wrong with
>> the code above that should warrant a warning?
>
> I think the warning is correct, and the code shoud use const char *type_CtrlAlt

Thank you.  I was confused by the wording of the warning, but now I 
understand the issue.

Closing.

Ken

Previous Next

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