Antony T Curtis wrote:
>
> On 2 Oct 2008, at 07:11, Stewart Smith wrote:
>
>> On Thu, Oct 02, 2008 at 09:04:47AM -0400, Jay Pipes wrote:
>>> Paul McCullagh wrote:
>>>>> It's probably useful to go through each of the patches there and re-do
>>>>> some of the work. A bunch of the compiler warnings I solved in rather
>>>>> silly ways. e.g. unused parameters, i just did (void)foo; instead
>>>>> of the
>>>>> better solution of removing the parameter.
>>>>
>>>> I'm OK with this solution for the moment. Some of these cannot be
>>>> changed because they involve callbacks which sometimes/may use the
>>>> parameters.
>>>
>>> -1 Please let's use __attribute__((unused)) as it is clearer and
>>> indicates to the caller that the argument is not currently used...the
>>> (void)foo; approach doesn't make it clear in the function declaration
>>> that the parameter isn't used.
>>
>> I remember previously having portability issues with this approach
>> (rather than cast to (void))... can't remember which platform though...
>> I'm guessing HPUX or Solaris or Windows... they usually cause me pain
>> and memory loss.
>
> using (void)x to silence unused parameters is not good and can cause
> warnings by itself with some compilers. (statement has no effect)
>
> An option available for most C++ compilers is to omit the argument
> name... so..
>
> int test1(int a, int b __attribute__((unused)), int c)
> { return a + c; }
>
> can be written as:
>
> int test2(int a, int, int c)
> { return a + c; }
>
> The drawback... it won't compile in C mode.
>
> It may be desirable to set a define depending upon the behavour of the
> compiler:
>
> #ifdef HAVE_ATTRIBUTE_UNUSED
> #define UNUSED(X) X __attribute__ ((UNUSED))
> #endif
> #define UNUSED(X)
> #endif
If you do a
#ifndef __GNUC__
#define __attribute__(X)
#endif
You can get away with using __attribute__ in the GNU way. No need to have
special macros for the code (well... there will still be a definition of
__attribute__, but that is quite well-known).
Just my few cents,
Mats Kindahl
> int test3(int a, int UNUSED(b), int c)
> { return a + c; }
>
> Regards,
> Antony.
>
>
>
> _______________________________________________
> Mailing list: https://launchpad.net/~drizzle-discuss
> Post to : [email protected]
> Unsubscribe : https://launchpad.net/~drizzle-discuss
> More help : https://help.launchpad.net/ListHelp
--
Mats Kindahl
Lead Software Developer
Replication Team
MySQL AB, www.mysql.com
begin:vcard
fn:Mats Kindahl
n:Kindahl;Mats
org:Sun Microsystems
adr;quoted-printable:;;Tegv=C3=A4gen 3;Storvreta;SE;74334;Sweden
email;internet:[EMAIL PROTECTED]
title:Lead Replication Software Developer
x-mozilla-html:FALSE
version:2.1
end:vcard
_______________________________________________
Mailing list: https://launchpad.net/~drizzle-discuss
Post to : [email protected]
Unsubscribe : https://launchpad.net/~drizzle-discuss
More help : https://help.launchpad.net/ListHelp
