Fix the -fvisibility=hidden settings to work with the linux shlib build....

Fix the -fvisibility=hidden settings to work with the linux shlib build.

Inside chromium's src/build/common.gypi, when a shared library build is
specified, the -fvisibility=hidden flag is explicitly removed via a
cflags! exclusion.  This overrides all cflags set in lower gyp files. It
is also incorrect for building plugins.  To get around this, we use
a gyp pattern list so that the -fvisibility=hidden flag is readded by gyp
after the exclusion is applied.

-fvisibility=hidden is particularly important here because Module::Get()
has a second definition inside chromium that is used by the internal
pepper plugins.  Without -fvisibility=hidden, the symbol resolution
gets crossed after the plugin is loaded such that the browser internal
verison of Module::Get() is invoked by ppapi's C++ wrappers even though
the it is the plugin's version of Module::Get() that is initialized.
This usually manifests itself as all externally loaded ppapi plugins that
use the ppapi C++ wrappers failing to load.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=164

[awong (On leave), 2010-07-15 21:11:31]

More internal pepper fun.  When I checked in the chromoting plugin, the linux
dbg shlib builders all started dying.  Explanation is in the change description.

Gyp workaround is from markmentovai.

Mark CCed in case he has comments.  Jam CCed cause he's messing with linux
pepper plugins too.

[Mark Mentovai - out til August, 2010-07-15 21:13:33]

http://codereview.chromium.org/3018003/diff/1/2
File ppapi.gyp (right):

http://codereview.chromium.org/3018003/diff/1/2#newcode18
ppapi.gyp:18: 'cflags': ['-fPIC'],
Maybe put -fvisibility=hidden here too so you know for sure that you have
something to include?

http://codereview.chromium.org/3018003/diff/1/2#newcode21
ppapi.gyp:21: # -fvisibility=hidden get stripped by the exclusion in of
common.gypi
in of

[awong (On leave), 2010-07-15 21:18:58]

Replaced Darin with Brett as a reviewer since Darin seems to be busy today.

On 2010/07/15 21:13:33, Mark Mentovai wrote:
> http://codereview.chromium.org/3018003/diff/1/2
> File ppapi.gyp (right):
> 
> http://codereview.chromium.org/3018003/diff/1/2#newcode18
> ppapi.gyp:18: 'cflags': ['-fPIC'],
> Maybe put -fvisibility=hidden here too so you know for sure that you have
> something to include?

Good idea. Done.

> http://codereview.chromium.org/3018003/diff/1/2#newcode21
> ppapi.gyp:21: # -fvisibility=hidden get stripped by the exclusion in of
> common.gypi
> in of

done.

[Mark Mentovai - out til August, 2010-07-15 21:20:20]

STOP. Grammartime!

http://codereview.chromium.org/3018003/diff/2002/5001
File ppapi.gyp (right):

http://codereview.chromium.org/3018003/diff/2002/5001#newcode20
ppapi.gyp:20: # This is needed to make Linux shlib build happy. Without this,
make the Linux

http://codereview.chromium.org/3018003/diff/2002/5001#newcode21
ppapi.gyp:21: # -fvisibility=hidden get stripped by the exclusion in common.gypi
gets

[awong (On leave), 2010-07-15 21:25:44]

On 2010/07/15 21:20:20, Mark Mentovai wrote:
> STOP. Grammartime!

Hah. Yessir Mr. Hammer.


> http://codereview.chromium.org/3018003/diff/2002/5001
> File ppapi.gyp (right):
> 
> http://codereview.chromium.org/3018003/diff/2002/5001#newcode20
> ppapi.gyp:20: # This is needed to make Linux shlib build happy. Without this,
> make the Linux

done 

> http://codereview.chromium.org/3018003/diff/2002/5001#newcode21
> ppapi.gyp:21: # -fvisibility=hidden get stripped by the exclusion in
common.gypi
> gets

done


and proofread now.

me was never none too greater at me inglish.

[brettw, 2010-07-15 21:53:51]

LGTM