[PATCH, libiberty]: Avoid 'right-hand operand of comma expression has no effect' when compiling regex.c

[Ian Lance Taylor]

On Thu, Mar 13, 2014 at 11:24 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On Thu, Mar 13, 2014 at 6:30 PM, Ian Lance Taylor <iant@google.com> wrote:
>> On Thu, Mar 13, 2014 at 3:36 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
>>>
>>> Attached patch changes the return value of the bzero macro to void, as
>>> defined in a 4.3BSD:
>>>
>>>        void bzero(void *s, size_t n);
>>>
>>> As an additional benefit, the changed macro now generates warning when
>>> its return value is used (which is *not* the case in regex.c):
>>
>> I'm not worried about anybody using the return value incorrectly in
>> this file.  I think we should just
>>
>> #      define bzero(s, n)       memset (s, '\0', n)
>>
>> I'll approve that change if it works.
>
> Attached patch compiles without warnings as well. However, in some
> case, we have similar situation with unused return value of
>
> #     define memcpy(d, s, n)    (bcopy (s, d, n), (d))
>
> so, I put (void) casts to memcpy call to avoid eventual "right-hand
> operand of comma expression has no effect" warnings there.
>
> 2014-03-13  Uros Bizjak  <ubizjak@gmail.com>
>
>     * regex.c (bzero) [!_LIBC]: Define without coma expression.
>     (regerror): Cast the call to memcpy to (void) to avoid unused
>     value warnings.
>
> Is this version acceptable for mainline?

This is OK.

Thanks.

Ian