Make some global pointers const void* const.

Make some global pointers const void* const.

Otherwise the thing the pointers point to can change.

Committed: https://crrev.com/3b6a2f11c70c112a2c15ddb996df78d665486ae1
Cr-Commit-Position: refs/heads/master@{#350785}

[Lei Zhang, 2015-09-25 01:55:03]

thestig@chromium.org changed reviewers:
+ brettw@chromium.org

[Lei Zhang, 2015-09-25 01:55:04]

One more for the road.

[brettw, 2015-09-25 03:10:18]

Isn't that backwards? I thought
  const void * == void const *
means that the data is const but the pointer itself isn't (since the pointer is
returned by value the constness of the pointer itself is irrelevant). I think
that's all we need, right?

[Lei Zhang, 2015-09-25 03:30:23]

On 2015/09/25 03:10:18, brettw wrote:
> Isn't that backwards? I thought
>   const void * == void const *
> means that the data is const but the pointer itself isn't (since the pointer
is
> returned by value the constness of the pointer itself is irrelevant). I think
> that's all we need, right?

Nope, they are not the same. See below. Really we want both here because neither
the pointer nor its value should change.


const int* p = NULL;
*p = 1;  // error: assignment of read-only location ‘* p’

int x = 0;
const int* p = NULL;
p = &x;  // no error

int x = 0;
int* const p = NULL;
p = &x;  // error: assignment of read-only variable ‘p’

int x = 0;
int* const p = NULL;
*p = 1;  // no error

[brettw, 2015-09-25 04:51:25]

Okay, I understood it properly, but for some reason though some of these were
return values for functions, which would be pointless:
  const void* const GetFoo();

LGTM

https://codereview.chromium.org/1370603002/diff/1/base/debug/task_annotator.cc
File base/debug/task_annotator.cc (right):

https://codereview.chromium.org/1370603002/diff/1/base/debug/task_annotator.c...
base/debug/task_annotator.cc:48: const void* const program_counter =
This one seems unnecessary. I usually prefer not to mark all the random local
variables const.

[Lei Zhang, 2015-09-25 05:35:40]

https://codereview.chromium.org/1370603002/diff/1/base/debug/task_annotator.cc
File base/debug/task_annotator.cc (right):

https://codereview.chromium.org/1370603002/diff/1/base/debug/task_annotator.c...
base/debug/task_annotator.cc:48: const void* const program_counter =
On 2015/09/25 04:51:25, brettw wrote:
> This one seems unnecessary. I usually prefer not to mark all the random local
> variables const.

Reverted

[Lei Zhang, 2015-09-25 05:37:53]

The CQ bit was checked by thestig@chromium.org

[Lei Zhang, 2015-09-25 05:37:54]

The patchset sent to the CQ was uploaded after l-g-t-m from brettw@chromium.org
Link to the patchset: https://codereview.chromium.org/1370603002/#ps40001
(title: "rebase")

[commit-bot: I haz the power, 2015-09-25 05:38:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1370603002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1370603002/40001

[commit-bot: I haz the power, 2015-09-25 06:12:44]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-09-25 06:12:46]

Try jobs failed on following builders:
  cast_shell_android on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_andr...)

[Lei Zhang, 2015-09-25 06:44:36]

The CQ bit was checked by thestig@chromium.org

[commit-bot: I haz the power, 2015-09-25 06:44:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1370603002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1370603002/40001

[commit-bot: I haz the power, 2015-09-25 08:17:28]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-09-25 08:18:15]

Patchset 3 (id:??) landed as
https://crrev.com/3b6a2f11c70c112a2c15ddb996df78d665486ae1
Cr-Commit-Position: refs/heads/master@{#350785}