Alignment issue of iobuf functions

[Neal H. Walfield]

Hi Niibe,

On Tue, 05 Jan 2016 02:53:05 +0100,
NIIBE Yutaka wrote:
> Then, I see compiler warnings like:
> =========================
> ../../gnupg/common/iobuf.c: In function `file_filter':
> ../../gnupg/common/iobuf.c:581:8: warning: cast increases required
> alignment of target type [-Wcast-align]
>        *(char **) buf = "file_filter(fd)";
>         ^
> =========================
> 
> This is because of the argument BUF is declared as byte * and we cast
> to (char **), where the alignment condition for (byte *) and the one
> for (char **) could be different.  So, the warning is relevant.
> 
> I think that our usage of (byte *) here is actually (void *).  I'm not
> sure if changing to (void *) is better or not.

Unfortunately, we are overloading the buf parameter too much.

I'm guessing this is not the only warning that you getting for this,
right?  file_es_filter and block_filter, for instance, use the same
pattern.

:) Neal