[DBus] Explicitly instantiate dbus::Property variants

[DBus] Explicitly instantiate dbus::Property variants

dbus::Property<std::vector<uint8> > isn't instantiated in libdbus in non-ChromeOS build + latest clang.
That causes instantiation of the template in dbus_unittests, and causes link failure.

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=280264

[tzik, 2014-06-24 05:03:39]

PTL.

Latest clang fails to link dbus_unittest.
The template specializations seem to need EXPORT declaration.

I don't understand why other similar specialization doesn't need the EXPORT,
though it builds on my machine.

The error message was:

obj/dbus/dbus_unittests.property_unittest.o:../../dbus/property_unittest.cc:vtable
for dbus::Property<std::__1::vector<unsigned char, std::__1::allocator<unsigned
char> > >: error: undefined reference to
'dbus::Property<std::__1::vector<unsigned char, std::__1::allocator<unsigned
char> > >::PopValueFromReader(dbus::MessageReader*)'
obj/dbus/dbus_unittests.property_unittest.o:../../dbus/property_unittest.cc:vtable
for dbus::Property<std::__1::vector<unsigned char, std::__1::allocator<unsigned
char> > >: error: undefined reference to
'dbus::Property<std::__1::vector<unsigned char, std::__1::allocator<unsigned
char> > >::AppendSetValueToWriter(dbus::MessageWriter*)'
clang-3.5: error: linker command failed with exit code 1 (use -v to see
invocation)

[tzik, 2014-06-26 04:58:29]

Updated: other variant of dbus::Property are instantiated in chromeos=1 build
and exported.
That's why I hit the error only for dbus::Property<std::vector<uint8> >.

[keybuk, 2014-06-26 05:01:46]

https://codereview.chromium.org/354553002/diff/20001/dbus/property.h
File dbus/property.h (right):

https://codereview.chromium.org/354553002/diff/20001/dbus/property.h#newcode353
dbus/property.h:353: class Property : public PropertyBase {
what about the other classes, e.g. PropertyBase and PropertySet?

[tzik, 2014-06-26 05:25:56]

https://codereview.chromium.org/354553002/diff/20001/dbus/property.h
File dbus/property.h (right):

https://codereview.chromium.org/354553002/diff/20001/dbus/property.h#newcode353
dbus/property.h:353: class Property : public PropertyBase {
On 2014/06/26 05:01:46, keybuk wrote:
> what about the other classes, e.g. PropertyBase and PropertySet?

Since PropertySet is not a template class, its member's symbols are created and
exported in property.cc, which is in libdbus.
For PropertyBase, Init() is called only from property.cc, which doesn't cause
link failure.
Other non-inline members are pure virtual, I'm not familiar to this case, but it
looks like calling virtual functions doesn't need symbol export.

[keybuk, 2014-06-26 23:06:18]

lgtm

[tzik, 2014-06-27 03:34:28]

The CQ bit was checked by tzik@chromium.org

[commit-bot: I haz the power, 2014-06-27 03:36:28]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/tzik@chromium.org/354553002/20001

[commit-bot: I haz the power, 2014-06-27 07:58:44]

Change committed as 280264

[tzik, 2014-06-27 08:08:23]

A revert of this CL has been created in
https://codereview.chromium.org/353063007/ by tzik@chromium.org.

The reason for reverting is: This causes link error:
http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%2....