mac: Suppress partial availability warnings.

mac: Suppress partial availability warnings.

The warnings are emitted when a translation unit attempts to reference
a function whose availability is newer than the deployment target.

BUG=471823

[erikchen, 2015-04-28 22:49:12]

erikchen@chromium.org changed reviewers:
+ mark@chromium.org

[erikchen, 2015-04-28 22:49:12]

mark: Please review.

[Mark Mentovai, 2015-04-29 00:33:52]

https://codereview.chromium.org/1109273002/diff/20001/util/mach/exception_typ...
File util/mach/exception_types.cc (right):

https://codereview.chromium.org/1109273002/diff/20001/util/mach/exception_typ...
util/mach/exception_types.cc:40: int proc_get_wakemon_params(pid_t pid, int*
rate_hz, int* flags);
Does this destroy the weak import when the deployment target is under 10.9? The
comment above indicates that this is important, and it’s used on line 91 below.

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc
File util/stdlib/strnlen.cc (right):

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:20: // Forward declare a method only available on OSX
10.7+ so that
There’s nothing really “forward” about this, it’s just your own declaration.

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:22: size_t strnlen(const char*, size_t);
The parameters should be named, and this ought to be in an extern "C" block.
(Did you test this?)

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:27: #if defined(OS_MACOSX) &&
MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_7
We should be sharing this #ifdef. You can move it outside of namespace crashpad.

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:30: if (::strnlen) {
This is a check to see whether the symbol exists at runtime, and relies on weak
import of strnlen. Does the redeclaration impact weak import?

[erikchen, 2015-04-30 00:34:42]

mark: PTAL

https://codereview.chromium.org/1109273002/diff/20001/util/mach/exception_typ...
File util/mach/exception_types.cc (right):

https://codereview.chromium.org/1109273002/diff/20001/util/mach/exception_typ...
util/mach/exception_types.cc:40: int proc_get_wakemon_params(pid_t pid, int*
rate_hz, int* flags);
On 2015/04/29 00:33:52, Mark Mentovai wrote:
> Does this destroy the weak import when the deployment target is under 10.9?
The
> comment above indicates that this is important, and it’s used on line 91
below.

This does not destroy the weak import.

"""
 $
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/dyldinfo
-bind ~/projects/chromium_official/src/out_static/Release/crashpad_handler |
grep proc_get
__DATA  __got            0x10004C110    pointer      0 libSystem       
_proc_get_wakemon_params (weak import)
"""

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc
File util/stdlib/strnlen.cc (right):

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:20: // Forward declare a method only available on OSX
10.7+ so that
On 2015/04/29 00:33:52, Mark Mentovai wrote:
> There’s nothing really “forward” about this, it’s just your own declaration.

Right. Updated the comment.

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:22: size_t strnlen(const char*, size_t);
On 2015/04/29 00:33:52, Mark Mentovai wrote:
> The parameters should be named, and this ought to be in an extern "C" block.
> (Did you test this?)

I've done as you suggested. The extern "C" seems to have no effect on the final
product. (tests passes both with and without, dyldinfo shows the same symbol as
well)

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:27: #if defined(OS_MACOSX) &&
MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_7
On 2015/04/29 00:33:52, Mark Mentovai wrote:
> We should be sharing this #ifdef. You can move it outside of namespace
crashpad.

Done.

https://codereview.chromium.org/1109273002/diff/20001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:30: if (::strnlen) {
On 2015/04/29 00:33:52, Mark Mentovai wrote:
> This is a check to see whether the symbol exists at runtime, and relies on
weak
> import of strnlen. Does the redeclaration impact weak import?

It does not.

$
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/dyldinfo
-bind ~/projects/chromium_official/src/out_static/Release/crashpad_handler  |
grep strnlen
__DATA  __got            0x10004C118    pointer      0 libSystem        _strnlen
(weak import)

[Mark Mentovai, 2015-04-30 13:53:50]

LGTM

https://codereview.chromium.org/1109273002/diff/40001/util/stdlib/strnlen.cc
File util/stdlib/strnlen.cc (right):

https://codereview.chromium.org/1109273002/diff/40001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:46: #endif
Blank line before this.

[erikchen, 2015-05-01 18:09:47]

https://codereview.chromium.org/1109273002/diff/40001/util/stdlib/strnlen.cc
File util/stdlib/strnlen.cc (right):

https://codereview.chromium.org/1109273002/diff/40001/util/stdlib/strnlen.cc#...
util/stdlib/strnlen.cc:46: #endif
On 2015/04/30 13:53:50, Mark Mentovai wrote:
> Blank line before this.

Done.

[erikchen, 2015-05-01 18:09:55]

The CQ bit was checked by erikchen@chromium.org

[erikchen, 2015-05-01 18:09:55]

The patchset sent to the CQ was uploaded after l-g-t-m from mark@chromium.org
Link to the patchset: https://codereview.chromium.org/1109273002/#ps60001
(title: "Comments from mark, round two.")

[commit-bot: I haz the power, 2015-05-01 18:14:05]

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

[commit-bot: I haz the power, 2015-05-01 18:14:07]

Commit queue rejected this change because it did not recognize the base URL.
Please commit your change manually.

[Mark Mentovai, 2015-05-01 18:18:01]

Committed
https://chromium.googlesource.com/crashpad/crashpad/+/3d216f5516d78239e760e93...