On Thu, Apr 19, 2012 at 10:35 PM, Jim Meyering <j...@meyering.net> wrote:
> Richard Guenther wrote:
>> Sure, my point was that the
>>
>> if (strlen (m->name) >= sizeof buf)
>> {
>> error ("%s:%d:mode name \"%s\" is too long",
>> m->file, m->line, m->name);
>> continue;
>> }
>>
>> check does not account for the (conditional) prepending of 'C' and the
>> snprintf would silently discard the last character of the name.
>
> Here's a patch for that. (passes make bootstrap)
> Incidentally it removes the name-length limitation of 7 and it hoists
> the xmalloc, which induces the single added free-before-continue.
> There was some clean-up along the way: "q" was easy to eliminate, and
> I pulled the two identical snprintf calls out of the "if" block and
> replaced them with the buf[0] assignment and memcpy.
Ok.
Thanks,
Richard.
>
> 2012-04-19 Jim Meyering <meyer...@redhat.com>
>
> * genmodes.c (make_complex_modes): Don't truncate a mode name of
> length 7 or more when prepending a "C". Suggested by Richard Guenther.
>
>
> gcc/genmodes.c | 32 +++++++++++++-------------------
> 1 file changed, 13 insertions(+), 19 deletions(-)
>
> diff --git a/gcc/genmodes.c b/gcc/genmodes.c
> index 6bbeb6f..84517b9 100644
> --- a/gcc/genmodes.c
> +++ b/gcc/genmodes.c
> @@ -427,7 +427,6 @@ make_complex_modes (enum mode_class cl,
> {
> struct mode_data *m;
> struct mode_data *c;
> - char buf[8];
> enum mode_class cclass = complex_class (cl);
>
> if (cclass == MODE_RANDOM)
> @@ -435,6 +434,7 @@ make_complex_modes (enum mode_class cl,
>
> for (m = modes[cl]; m; m = m->next)
> {
> + char *p, *buf;
> size_t m_len;
>
> /* Skip BImode. FIXME: BImode probably shouldn't be MODE_INT. */
> @@ -442,40 +442,34 @@ make_complex_modes (enum mode_class cl,
> continue;
>
> m_len = strlen (m->name);
> - if (m_len >= sizeof buf)
> - {
> - error ("%s:%d:mode name \"%s\" is too long",
> - m->file, m->line, m->name);
> - continue;
> - }
> + /* The leading "1 +" is in case we prepend a "C" below. */
> + buf = (char *) xmalloc (1 + m_len + 1);
>
> /* Float complex modes are named SCmode, etc.
> Int complex modes are named CSImode, etc.
> This inconsistency should be eliminated. */
> + p = 0;
> if (cl == MODE_FLOAT)
> {
> - char *p, *q = 0;
> - /* We verified above that m->name+NUL fits in buf. */
> memcpy (buf, m->name, m_len + 1);
> p = strchr (buf, 'F');
> - if (p == 0)
> - q = strchr (buf, 'D');
> - if (p == 0 && q == 0)
> + if (p == 0 && strchr (buf, 'D') == 0)
> {
> error ("%s:%d: float mode \"%s\" has no 'F' or 'D'",
> m->file, m->line, m->name);
> + free (buf);
> continue;
> }
> -
> - if (p != 0)
> - *p = 'C';
> - else
> - snprintf (buf, sizeof buf, "C%s", m->name);
> }
> + if (p != 0)
> + *p = 'C';
> else
> - snprintf (buf, sizeof buf, "C%s", m->name);
> + {
> + buf[0] = 'C';
> + memcpy (buf + 1, m->name, m_len + 1);
> + }
>
> - c = new_mode (cclass, xstrdup (buf), file, line);
> + c = new_mode (cclass, buf, file, line);
> c->component = m;
> }
> }
> --
> 1.7.10.208.gb4267
