[Mesa-dev] [PATCH mesa] glx: remove dead code

[Emil Velikov]

On 6 September 2017 at 17:17, Adam Jackson <ajax at redhat.com> wrote:
> On Fri, 2017-09-01 at 15:04 +0100, Eric Engestrom wrote:
>> These fields were added in 2d94601582 but never used; hasPresent was
>> never set, while the other ones were set but never read.
>
> I think this patch is wrong:
>
>> -   dri3_reply = xcb_dri3_query_version_reply(c, dri3_cookie, &error);
>> -   if (!dri3_reply) {
>> -      free(error);
>> -      goto no_extension;
>> -   }
>
> You're not just removing the dead stores into the display state, you're
> also removing the checks for whether the extensions exist at all. The
> DRI3 loader is definitely not going to work if DRI3 and Present aren't,
> er, present.
>
I'm not that much of an expert on things XCB, so perhaps a silly question.
Isn't the presence checked with the code just above the removed hunk? Namely:

extension = xcb_get_extension_data(c, &xcb_dri3_id);
if (!(extension && extension->present))
  return NULL;

extension = xcb_get_extension_data(c, &xcb_present_id);
if (!(extension && extension->present))
  return NULL;

-Emil