Paul Eggert wrote:
> On 12/13/2017 01:38 AM, Tim Rühsen wrote:
> > Here is a patch to silence this warning:
> >
> > glob.c: In function 'rpl_glob':
> > glob.c:618:64: warning: pointer of type 'void *' used in arithmetic
> > [-Wpointer-arith]
> > err = getpwnam_r (s.data, &pwbuf, s.data + ssize,
> >
> >
> > With Best Regards, Tim
> >
> Thanks, I tweaked it slightly to avoid inserting a cast (as it's better
> to avoid casts when it's easy), and installed the attached patch into
> Gnulib, in your name.
... and I've added the ChangeLog entry for it.
But, when we look at the definition
struct scratch_buffer {
void *data; /* Pointer to the beginning of the scratch area. */
size_t length; /* Allocated space at the data pointer, in bytes. */
...
};
it seems quite natural to do pointer arithmetic on 'data'. Namely, this will
happen each time a scratch_buffer gets booked by several (not just one)
pieces of memory.
Therefore I would suggest to change the type of the 'data' field to 'char *'
in gnulib. I know that in glibc this is not needed, because glibc assumes GCC
and GCC supports 'void *' arithmetic as an extension.
Rationale: 'scratch_buffer' is a module of its own right in gnulib, and
may get more uses, in order to avoid stack overflows.
Bruno
